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Science Science 7
All rights reserved with the publishers.Project Directors: Abu Zar Ghaffari Gohar
Altaf Hussain GoharProject Manager: Tariq Mehmood SyanWriter: Dr. Akram MalikComposing by: Farhan Naseem
Key Book
Printing Manager:Processed by: RazHam Publishing
ServicesDesigned at: Gohar Designing LabHead office:
Zaheer Ahmad
Gohar Curriculum Researchand Development Centre
Gohar Centre, 7/c, Marther Street,Lower Mall, Lahore, +92-423-7358207
CONTENTSNo. Unit Name Page
Unit 1 What is Science? 3
Unit 2 Digestion and Respiration in Human 8
Unit 3 Transport in Human and Plants 13
Unit 4 Reproduction in Plants 20
Unit 5 Living Together in an Environment 24
Unit 6 Water 30
Unit 7 Structure of an Atom 35
Unit 8 Changes and Processes Around us 41
Unit 9 Transmission of Heat 46
Unit 10 Refraction and Dispersion of Light 51
Unit 11 Waves and Sound 57
Unit 12 Electricity 63
Unit 13 Exploring the Space 69
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Unit 1
What is Science?Section Review I
Q1. What is science?Ans: Science is the system of acquiring knowledge
through observation and experiments.Q2. What do engineers do?Ans: Engineers design and make new machines for
industry.Q3. Writethestagesofthescientificmethod.Ans:Followingarethestagesofthescientificmethod: 1. Identifying Problem 2. Gathering information about the problem 3. Forming a Hypothesis 4. Do experiments 5. Data Analyzing 6. Draw conclusionsQ4. Which are main branches of science? Define
Chemistry.Ans: Chemistry, physics, biology and mathematics are
the main branches of science. Chemistry is the study of matter and changes in it.Q5. Whatthingsdointerestmathematician?Ans: Anything with numbers interest mathematicians.
Section Review II
Q1. WritethreecontributionsofAl-Raziinscience.Ans: i. Heclassifiedsubstancesasplants,animalsand
minerals.
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ii. He found treatment for kidney and bladder stones.
iii. He explained the nature of various infective diseases like smallpox and measels.
Q2. WhoisthefounderofmodernAlgebra?Ans: Musa Al-Khwarizmi is considered as the founder of
modern algebra.Q3. Whodiscoveredradioactivity?Ans: Madame Marie Curie discovered radioactivity.Q4. Defineunit.Whatistheunitofmass?Ans: A unit is the standard amount for any measurement.
Grams(g) and kilograms(kg) are the units to measure mass.
Q5. Whatwasthenameoftheinventorofballpointpen?
Ans:JohnLoudinventedthefirstballpointpen.Unit Review
Science Words calculation, experiment, mass, unit, conclusion Fillintheblanksusingthesciencewords.1. Kilogram is the unit of _______.2. A mathematician uses the method of _______ to
solve problems.3. On the basis of analysis of the recorded data, a
scientist comes to a _______.4. A _______ is a standard quantity.5. _______ is the most important part of a scientist’s
work.
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Answer: 1. mass 2. calculation 3. conclusion 4. unit 5. experiment
MultipleChoiceQuestion Circletheletterofthebestanswer.1. Ahypothesisistestedbya: (a) conclusion (b) data (c) experiment (d) inference2. Who studies plants, animals, microorganisms
andtheirbehaviours? (a) a chemist (b) a biologist
(c) a geologist (d) a physicist3. Degree Celsius (°C) or Degree Fahrenheit (°F)
areunitsof: (a) time (b) volume (c) length (d) temperature4. Whoisthefounderofmodernalgebra? (a) Newton (b) Al-Dinawari (c) Al-Khwarizmi (d) Al-Razi5. Oxygengaswasdiscoveredby: (a) Charles Darwin (b) Joseph Proust
(c) Marie Curie (d) Joseph PriestlyAnswer: 1. (c) 2. (b) 3.(d) 4. (c) 5. (b)
DetailedAnswerQuestionsQ1. Describedifferentstagesofthescientificmethod.Ans: ScientificMethod:Scientistsusescientificmethod
tosolvescientificproblems.Itsimportantstepsare
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as follows:i. Identifyingascientificproblemisthefirststep
ofscientificmethod.ii. Scientists gather informations about the
problem.iii. Formingahypothesis is an important step in
solving a problem. It is a supposed solution to the problem.
iv. Scientists arrange experiments to test hypothesis.
v Scientists collect informations called data from experiments and analyze it.
vi Finally they word conclusion to explain the solution of the problem.
Q2. Write briefly about the measurement of time,length,mass,temperatureandvolume.
Ans: Measurement in Science: Measurement is basic to science. Without measurement scientists cannot work at all.i. Time is measured in seconds (Sec). Seconds
make minutes and hours.ii. Length is measured in metres (m). Centimetres,
millimetres and kilometres are other units of length.
iii. Mass is measured in grams (g) and kilograms (kg).
iv. Temperature is measured in degree celsius (°C) or degree Fahrenheit (°F).
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v. Volume is measured in litres (l) and millilitres (ml).
3. Writecontributionsofthefollowingscientists. (a)MusaAl-Khwarizmi (b)MadameCurieAns: (a)MusaAl-Khwarizmi:Some of the contributions
of this great scientist are:i. He is founder of modern algebra.ii. He gave us arabic numerals.iii. He developed sine, cosine, etc. tables.iv. He described simple equations like:
nx=mv. He wrote several books like Kitab al-Jabr.
(b)MadameCurie:Major contributions of Madame Curie are:i. She discovered radioactivity.ii. She discovered that radiation from radium metal
can be used to kill tumors.iii. ShedesignedthefirstmobileX-raymachine.iv. She won Noble Prize for her discoveries and
inventions.
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Unit 2
DigestionandRespirationin Human
Section Review I
Q1. What is digestion?Ans: The process of changing complex food into simpler
substances is called digestion.Q2. Wheredoesdigestedfoodabsorbinourblood?Ans: The digested food is absorbed in small intestine and
reaches our blood.Q3. Whatarethesymptomsofconstipation?Ans: Following are the symptoms of constipation:
i. Difficultorpainfulpassingofstoolii. Cramps in abdomeniii. Severe abdominal painiv. Blood in stoolv Pain in rectum
Section Review II
Q1. Whatisrespiration?Ans: The process in which food and oxygen in our body
burn to produce energy, is called respiration.Q2. Whichbloodvesselsinthelungshelpyourbody
takeinandgiveoffgases?Ans: The capillaries in the lungs help our body take in
and give off gases.Q3. Comparebrieflythebreathingandtheburning.
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Ans: In both breathing and burning, oxygen is used to produce energy. In both processes, carbon dioxide and water are evolved.
Q4. Whatcausesairtomoveinandoutofthelungs?Ans: Our lungs have no muscles to move. It is diaphragm
that causes air to move in and out of the lungs. Diaphragm is a muscle.
Unit Review
Science Words esophagus, alveoli, duodenum, larynx ,diaphragm Fillintheblanksusingthesciencewords.1. The _________ is a large tube that runs from the
mouth to the stomach.2. Thefirstpartofsmallintestineiscalled_________.3. The grape-like clusters of tiny thin-walled balloons
in lungs are called _________.4. _________ is the upper part of a windpipe in our
throat.5. The dome-shaped muscle at the bottom of our chest
is called _________.
Answer: 1. esophagus 2. duodenum 3. alveoli 4. larynx 5. diaphragm
MultipleChoiceQuestion Circletheletterofthebestanswer.1. Waterisabsorbedinthe: (a) liver (b) esophagus
(c) small intestine (d) large intestine
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2. Airismoistened,filtered,andwarmedinthe: (a) larynx (b) nasal cavity
(c) pharynx (d) trachea3. Exchangeofgasesoccursbetweenthe__________
andcapillaries. (a) alveoli (b) bronchioles
(c) bronchi (d) trachea4. Theribcage_________whenyouexhale. (a) moves up (b) moves out
(c) moves down (d) stays the
Answer: 1. (d) 2. (b) 3.(a) 4. (c)
DetailedAnswerQuestionsQ1. Explain the process of digestion of food in the
mouthandthestomach.Ans: 1. Digestion inMouth:The process of digestion
starts in our mouth. The teeth and the tongue help to grind food. Saliva is mixed with the food. An enzyme digests carbohydrate part of the food. After some time the food is pushed to the pharynx.
2.DigestioninStomach:Our stomach is a muscular bag. Its walls secret gastric juice. This juice helps to digest protein part of our food. After a certain period of time partly digested food is pushed into the small intestine.
Q2. Describe the digestion of carbohydrates andproteins.
Ans: Digestion ofCarbohydrates:We eat wheat, rice, sugar, etc. All these things are carbohydrates.
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Digestion of the carbohydrates starts in the mouth. An enzyme amylase helps to digest carbohydrates, butfinaldigestionoccursinthesmallintestinewherepancreatic juice mixes with the food.
Digestionofproteins:Digestion of proteins occurs in the stomach. The hydrochloric acid and an enzyme pepsin help to digest proteins. But, again finaldigestionofproteinsoccursinsmallintestine.
Q3. Explainthehumanrespiratorysystem.Ans: Human Respiratory System: Respiration is the
process of producing energy in our body. In this process oxygen gas enters the lungs and carbon dioxide gas is released.
Our respiratory system consists of nasal cavity, pharynx, larynx, trachea and lungs.i. Air enters through our nose. In the nose, air is
cleaned and warm.ii. The moist, warm air moves into the pharynx
and then larynx.iii. Air then enters the wind-pipe or trachea.iv. The trachea divides into bronchi which enter the
lungs.v. Thebronchidivideintobronchiolesandfinally
reach to alveoli. Alveoli are tiny balloon-like Structures in our lungs. Exchange of gases between the blood and air takes place in alveoli.
vi. The oxygen gas is then taken to every cell to produce energy.
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vii. The carbon dioxide is taken back to lungs to release out.
Q4. Writenotesonthefollowing: i. Breathing Process ii.CommonColdAns: i.BreathingProcess:Breathing means intake of air
with more oxygen gas and give off the air with more carbon dioxide gas.
The Dome-Shaped muscle diaphragm helps in breathing.i. When rib muscles and diaphragm tighten and
move down, the lungs expand and air rushes in.ii. When rib muscles and diaphragm relax and
move up, the lungs are pressed and air goes out of the lungs.
ii.CommonCold:Common cold is an infection of respiratory system. Its common symptoms are:
Sore throat, runny nose, cough, sneezing headache etc.
During common cold get lots of rest drink plenty of water. If symptoms persist, consult your doctor.
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Unit 3
TransportinHumanandPlantsSection Review I
Q1. Whatispericardium?Ans: It is a protective sac around our heart. Pericardium
is filled with a fluid to reduce friction during theheartbeat.
Q2. Namethepartsofblood?Ans: Blood is a mixture of: i. plasma ii. red blood cells iii. white blood cells iv. plateletsQ3. Whatisthefunctionofhemoglobininredblood
cells?Ans: Hemoglobin in red blood cells transports oxygen
and carbon dioxide.Q4. Whatissphygmomanometer?Ans: Sphygmomanometer is a device that is used to
measure the blood pressure.Q5. Whichbloodvesselshelpinexchangeofmaterials
inyourbody?Ans: Capillaries help in exchange of materials in our
body.Section Review II
Q1. Whichcomplicationsarerelatedtodiabetes?Ans: High blood pressure, obesity, dry skin, blurred
vision, sores and painful calves are the complications related to diabetes.
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Q2. Whatisasthma?Ans: Asthma is an alergy of lungs. It causes attacks of
wheezing, shortness of breathing, chest tightness and coughing.
Q3. Howcanyouavoidheartdiseases?Ans: by taking low fat foods, by taking exercise and by
avoiding tensions we can avoid heart diseases.Q4. Whichdisorderofthecirculatorysystemiscalled
thesilentkiller?Ans: High blood pressure is called the silent killer.
Section Review III
Q1. Whicharethemajortissuesoftransportationinplants?
Ans: Xylem and phloem are the major tissues oftransportation in plants. Xylem tissue transportswater and phloem tissue supports food prepared in leaves.
Q2. Whatisosmosis?Ans: The movement of solvent particles from higher
concentration to lower concentration through a selectively permeable membrane.
Q3. Definealivetransport.Ans: Active transport is the movement of substances from
a region of low concentration to a region of higher concentration by the use of energy.
Q4. Whatistranspiration?Ans: The removal of water from the aerial parts of a plant
through stomata is called transpiration.
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Q5. Wheredoesmostofthephotosynthesistakeplaceinaplant?
Ans: Most of the photosynthesis takes place in leaves which are green in colour.
Q6. On which surface of leaf more stomata arepresent?
Ans: The lower epidermis of leaf contains more stomata.Unit Review
Science Words Diffusion, health, plasma, phloem, pancreas Fillintheblanksusingthesciencewords.1. _______ is the movement of materials from a
region of higher concentration to the region of lower concentration.
2. The liquid part of our blood is called _______.3. Any disorder in our circulatory system can affect
our _______.4. The food is transported in a plant body through
_______.5. Diabetes is a disorder of ______.
Answer: 1. Diffusion 2. plasma 3. health 4. phloem 5. pancreas
MultipleChoiceQuestion Circletheletterofthebestanswer.1. Bloodiscarriedawayfromtheheartin: (a) arteries (b) veins
(c) nerves (d) ureters
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2. Where does the exchange of food, oxygen andwastesoccur?
(a) in arteries (b) in veins (c) in capillaries (d) in lymph vessels
3. Movementofmaterialsinaplantfromaregionoflowerconcentrationtotheregionofhigherconcentrationbytheuseofenergyiscalled:
(a) osmosis (b) transpiration (c) active transport (d) diffusion
4. Which tissue of a plant transports water andmineralsfromrootstoleaves?
(a) xylem (b) phloem (c) bark (d) mesophyll
5. Thecellsthatcontainhemoglobinare: (a) platelets (b) bone cells
(c) white blood cells (d) red blood cells
Answer: 1. (a) 2. (c) 3.(c) 4. (a) 5. (d)
DetailedAnswerQuestionsQ1. Describethestructureofhumanheart.Ans: HumanHeart:Our heart is a pumping organ. It is
made of a strong muscle. The heart is enclosed in pericardium. There are four chambers in our heart: 1. Right atrium 2. Left atrium
3. Right Ventricle 4. Left ventricle Each atrium is separated from ventricle by a valve.
Our heart receives blood from the body in atria and expels it to the body from ventricles. Both ventricles contract at the same time and push blood out of the
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heart.Q2. Listanddescribethefourcomponentsofblood
andtheirfunctions.Ans: TheBlood:Our blood is a mixture of plasma, red
blood cells, white blood cells and platelets. Plasmais the liquid part of the blood. It consists of
water, food particles, oxygen and some wastes. All bloodcellsfloatinplasma.
Redbloodcellscontain hemoglobin to carry oxygen from lungs to every cell of our body. They are in great number.
White Blood cells save our body from harmful bacteria and other germs. They are in less number than red blood cells.
Plateletshelp clot the blood in case of injury. There are about 150,000 to 400,000 platelets in our body.
Q3. Describethatstructureofaplant’srootpermitsthemovementofmaterials.
Ans: Structure of roots permits movements ofmaterials:Nature has designed roots to permit the movement of materials.i. Rootsarefixedinthesoiltoabsorbwaterand
minerals.ii. Branches of roots increase their ability to absorb
water and minerals from soil.iii. The root cap protects the root from friction
during its growth.iv. The root hair help to absorb water and minerals
through their thin membranes.
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v. Xylem tissues in roots transport water to theleaves.
vi. Phloem tissues in roots transport food prepared in leaves.
Q4. Writebriefnoteson: i.Transpiration ii.Transplantation iii.Diabetes iv.AsthmaAns: i.Transpiration In trees water from the soil reaches to the top by
transpiration. Water forms an unbroken column from roots through the stem and into the leaves. From the leaves, water evaporates through stomata. This process is called transpiration. Roots absorb more water to maintain the water column in the tree.
ii.Transplantation Transplantation is the process in which doctors
remove body parts, organs or tissues from a healthy person and implant them into the body of another person (patient).
Skin, kidney, heart, liver, bone marrow, etc are transplanted most commonly.
iii.Diabetes It is a disease in which blood glucose levels are above
normal. The pancreas of a person cannot produce enough insulin to control the blood glucose or sugar level. Heart disease, kidney failure, blurred vision are the complications related to diabetes. Frequent urination, thirst, weight loss, dry skin, painful calves,etc are the symptoms of this problem. One
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can control its sugar level by taking regular exercise, by taking low fat food and by having reasonable body weight.
iv.Asthma Asthma is an alergy of lungs. It causes attacks of
wheezing, shortness of breath, coughing, etc. The triggers of this disease are molds, pollen grains,
cigarette, etc. We should not trigger them. Use plenty of water, it will give you relief. Doctor may advise you to use inhaler.
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Unit 4
ReproductioninPlantsSection Review I
Q1. Differentiate between asexual and sexualreproduction.
Ans. When only one organism can produce new generation, the process is called asexual reproduction.
When two organisms one male and other female produce gametes to form zygote, the process is called sexual reproduction.
Q2. Whataremaleandfemalepartsofaflower?Ans.Stamenis themalepartsofaflower.Carpel is the
femalepartofaflower.Q3. Whatispollination?Ans.ThetransferofpollengrainsfromStamenofaflower
to the carpel is called as pollination.Q4. Definefertilization.Ans. The union of male gamete (sperm) and female
gamete (egg) is called fertilization.
Section Review II
Q1. Whichpartofaseeddevelopsintothefirstroot?Ans.Radicalofseedembryodevelopsintothefirstroot.Q2. Which part of the flower usually develops into
thefruit?Ans.Theovaryofaflowerdevelopsintothefruit.Q3. Whichisthemostimportantpartofaseed?Ans. The embryo is the most important part of a seed.
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Unit Review
Science Words embryo, pollinate, seed coat, gametes, ovules, wind Fillintheblanksusingsciencewords.1. The _________ protects a seed.2. In sexual reproduction male and female _________
fuse to form zygote.3. The fertilized egg develops into the _________.4. Abeecanhelp_________aflower.5. Most grasses depend upon _________ for their
pollination.6. Ovary contains _________ which develop into
seeds.Answer: 1. seed coat 2. gametes 3. embryo
4. pollinate 5. wind 6. ovules
MultipleChoiceQuestion Fillintheblanksusingsciencewords.1. What helps protect seeds? (a) fruit (b) wind (c) bees (d) cotyledon 2. Whenabeelandsonaflower,itbrushesagainst: (a) seeds (b) cones (c) pollen grains (d) fruit3. Colourfulflowersareusuallypollinatedby: (a) clothing (b) wind (c) birds (d) insects4. The _________ contains food for the embryo:
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(a) stigma (b) endo sperm (c) pollen grain (d) root
5. The embryonic leaves of an embryo are: (a) root hairs (b) radicles
(c) plumules (d) cotyledons
Answer: 1. (a) 2. (c) 3.(d) 4. (b) 5. (d)
DetailedAnswerQuestionsQ1. Writeadetailednoteonpollinationinplants.Ans. Pollination The transfer of pollen grains from the stamen of a
flowertothestigmaofafloweriscalledpollination.This process is of great importance for plants.
It helps in the union of sperm and egg, so that embryo can develop in the ovule.
Kindsofpollination Therearetwokindsofpollinationinfloweringplant. i. Self-pollination ii. Cross-pollination Self-pollination occurs when pollen grains are
transferredfromthestamenofaflowertothecarpelofthesameflower.
Cross-pollination occurs when pollen grains are transferredfromthestamenofaflowertothecarpelofthefloweronanotherplant.
Pea plants are self-pollinated. Popoplar, willow and papaya, etc are cross pollinated.
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Q2. Explainfertilizationinplants.Ans. FertilizationinPlants Pollen grains reach to the stigma of the carpel during
pollination. Stigma has sticky surface. Pollen grains cling to the stigma. A pollen tube comes out of the pollen grain and enters stigma. It reaches to ovary through style. Here pollen tube attaches to an ovule and release its sperms in it. A sperm unites with the egg in ovule to form it a seed.
The union of sperm and egg is called fertilization. Later, the ovary changes into fruit.
Q3. Describethestructureofaseed,Ans. Seed After fertilization, an ovule changes into a seed. The
most important part of the seed is its embryo. Food is also stored in the seed to feed the embryo.
The embryo has following parts.i. Radicle is the part of an embryo that grows into
firstroot.ii. Plumulegrowsintofirstshootoftheplants.iii. Cotyledons supply food to the growing embryo.
Q4. Writeanoteonfruit.Ans. Fruit The ripened ovary is called fruit. A fruit develops
from the ovary after fertilization. The wall of the ovary becomes the wall of the fruit. It is called pericarp. Inside the ovary, ovules become seeds. A fruit may contain one or many seeds.
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Unit 5
Living Together in an Environment
Section Review I
Q1. Whatisahabitat?Ans. The place where an organism lives and reproduces is
called its habitat.Q2. What factors make a tropical rainforest best
suitableforplants?Ans. The abundant rainfall and high temperature make a
rainforest suitable for plants.Q3. Whatroledoessunlightplayinanecosystem?Ans. Sunlight is the ultimate source of energy on the
Earth. Plants use sunlight to make food. Almost all animals also need sunlight to the survive.
Q4. Whatispredation?Ans. The relationship between a predator and a prey is
called predation. A predator is an animal that kills the prey (another animal) to get its food.
Q5. Whatisaparasite?Ans. An organism that lives in or on the body of its host
to get food and shelter is called a parasite.Q6. Inwhichhabitatmoreorganismsarefound?Ans. A large number of plants and animals is found in
tropical rain forests. These forests get a lot of rain to meet the needs of plants and animals.
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Q7. Fromwheredoplantsobtainminerals?Ans. Plants obtain minerals from the soil through their
roots.Section Review II
Q1. Defineadaptation.Ans. Adaptation is a characteristic of an organism that
makesitfitforitsenvironment.Q2. Whichadaptationshaveducksandfrogstomove
in water?Ans. Webbed feet in ducks and frogs work like ores to
help easily move in water. Frogs also breathe through moist skin in water.
Q3. Howarepolarbearandarcticfoxabletoliveinfreezingcold?
Ans. The arctic fox and polar bear have thick fur on their bodies. This thick fur keeps their bodies warm in freezing cold.
Q4. Whatiscamouflage?Ans.Camouflage isawaybywhichananimalchanges
itscolourtoblendintoitssurrounding.Camouflagehelps to deceive the predators.
Q5. Whatareautotrophsandheterotrophs?Ans. Living organisms that can make their own food
are called autotrophs, e.g. green plants, algae and some other living things are autotrophs. Those organisms that cannot make their own food are called heterotrophs.
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Unit Review
Science Words community, water, decomposers, freezing cold,
producers Fillintheblanksusingthesciencewords.1. A coniferous forest is found in _______ environment.2. Plants use solar energy to make food, so they are
_______.3. _______ is essential for life.4. A _______ has many populations in it.5. Without proper control, _______ may also destroy
useful material in a habitat.
Answer: 1. freezing cold 2. producers 3. water 4. community 5. decomposers
MultipleChoiceQuestion Circletheletterofthebestanswer.1. The non-living part of any ecosystem is called
the: (a) habitat (b) community
(c) population (d) environment2. Organismsthatmaketheirownfoodarecalled: (a) autotrophs (b) heterotrophs
(c) consumers (d) decomposers3. Agreatvarietyofplantsandanimalsisfoundin
a: (a) desert habitat (b) pond habitat (c) tropical rainforest habitat (d) grassland habitat
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4. Seals,penguinsandturtlesuse_______tomovein water.
(a) fins (b) webbed feet (c)tubefeet (d)flippers
5. Bychangingcolour,ananimalcanblendintoitssurrounding and deceive its predator or prey.Thispropertyiscalled:
(a)camouflage (b)mimicry (c) predation (d) competition
Answer: 1. (a) 2. (a) 3.(c) 4. (d) 5. (a)
DetailedAnswerQuestionsQ1. Describefactorsthatcanbringdailyandyearly
changesinthehabitat.Ans. Following are the factors that can bring daily and
yearly changes in a habitat. LightIntensity Plants use sunlight to make food. Animals can
increase or decrease the number of plants in a habitat. It also affect the number of animals in the habitat.
Temperature Most organisms are active between 0°C and 45°C.
Very low or very high temperatures affect the number of plants and animals in a habitat.
Rainfall Water is essential for life. Where there is more water,
more organisms are found there.
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Carbondioxide Plants make their food by using carbon dioxide. It is
0.03 to 0.04 percent in air. A little increase favours plants to make food. More plants mean more organisms in a habitat. Some other factors such as migration, competition, predation, parasitism, decomposers and human effects also bring daily and yearly changes in a habitat.
Q2. Describeadaptationsofsomeaquaticanimalstoliveintheirhabitat.
Ans. SomeAdaptationsofaquaticAnimals:The most part of the Earth’s surface is covered with water. A large number of plants and animals live in water. They are adapted to live in water.i. Streamlined body shape is helpful to fishes,
dolphins, etc to move easily in water.ii. Webbed feet of ducks, seagulls and frogs help
them move in water.iii. Fishes use gills to breathe. They absorb oxygen
that is dissolved in water.iv. Duckweed and hyacinth are floating plants.
They have air spaces in their leaves. Their leaves have waxy covering to prevent the loss of water.
Q3. Explainafood-chainandafood-webwithexamples.
Ans. Food Chain: The feeding relationship among organisms is called a food-chain.
Example: 1. grass zebra lion
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2. leaves caterpillar bird hawk Food-Web: Several food chains in an ecosystem
overlap to form a network called food-web. Example: Animals like rabbits, grasshopper, cows,
deer, etc feed on grass. Snakes, hawks and wolves may eat rabbits. Similarly, grasshopper, cows and other grass-eaters are eaten by other big animals. There are several food chains involved here. These food chains form a food-web.
Q4. Writebriefnoteson: i.Grasslandhabitat ii.EffectsofhumidityonlifeAns. Grasslandhabitat:A grassy, windy and partly-dry
area is called the grassland. About one-forth of the total land on Earth is grassland. Deep-rooted grass grow very well in these fertile areas. Mostly grazing animals like the sheep, goats, cows, deer are found in grassland habitat.
EffectsofHumidityonlife:In tropical rainforest, there is great humidity. In humid conditions plants grow well. Several varieties of insects, snakes, lizards, frogs, parrots and jaguars are found in rainforests. We can say that humidity has a positive effect on life.
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Unit 6
WaterSection Review I
Q1. Identifythemainusesofwaterinourbody.Ans. Water is very important for our body as:
i. Itflusheswastedandharmfulsubstances fromthe body.
ii. It helps in the circulation of blood throughout our body.
iii. It keeps the body temperature at suitable level.Q2. Whyistheearthcalledthewaterplanet?Ans. Three fourth of the surface of our Earth is covered
with water. Water is also present beneath its surface. That is why the Earth is called the water planet.
Q3. Whatdoyoumeanbysoftandhardwater?Ans. The water in which the soap makes good lather is
called soft water. The water in which the soap makes curds is called hard water.
Q4. Whatdoyoumeanbyanartesianwell?Ans. A hole in the ground from which water is forced to
the surface by natural pressure is called an artesian well.
Q5. Whatisaglacier?Ans. Snow falls on mountains. Snow accumulates to form
glaciers. A glacier is a large mass of frozen water.
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Section Review II
Q1. Definewaterpollution.Ans. The addition of any substance that can harm living
organisms in water is called water pollution.Q2. In a sewagewater treatment plant,what is the
purposeofaddingchlorinetothewastewater?Ans. The chlorine is added to the waste water to kill germs
present in water.Q3. Definedistillationofwater.Ans. In distillation process, the water is heated to make
steam. The steam is then cooled down into pure or distilled water.
Q4. Wheredoweusemostofthewaterinourhomes?Ans. Most of the water in our homes is used in toilets
during showering.Q5. Giveafewtipsofconservewaterathome.Ans. To conserve water at home:
i. Turn off the shower while soapingii. Don’t brush your teeth using running water.
Take water in a glass.Unit Review
Science Words permeable, pollutants, acid rain, bacteria, fresh water Fillintheblanksusingthesciencewords.1. Water moves easily through porous rocks which are
called _______.2. Rivers, lakes and ponds are the sources of _______.3. Oxygen of air, and sunlight can kill many _______
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in water.4. Toxic gases in the air react with rain water to make
it _______.5. Harmful and unwanted substances in water are
called _______.
Answer: 1. permeable 2. fresh water 3. bacteria 4. acid rain 5. pollutants
MultipleChoiceQuestion Circletheletterofthebestanswer.1. Thewaterthatsoaksintothegroundiscalled: (a) earth water (b) ground water
(c) water table (d) aquifer2. Runningwatercollectsinlarge,deepdepressions
intheearth’scrustandforms: (a) a river (b) a stream
(c) a lake (d) a sea3. Placeswheregroundwaterbubblesorflowsout
ofcracksintherocksautomaticallyarecalled: (a) geysers (b) springs
(c) icebergs (d) lakes4. Themajorsourcesofwaterpollutionare: (a) human wastes (b) industrial wastes (c) agricultural chemicals (d) all of them5. Weusewaterduringshowering: (a) 10% (b) 20%
(c) 45% (d) 14%
Answer: 1. (b) 2. (c) 3.(b) 4. (d) 5. (c)
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DetailedAnswerQuestionsQ1. Explainhowwateristhemostessentialelement
oflife.Ans. Water forLife:Living things need water to stay
alive. They need water to grow, reproduce and carry out activities of life. Nearly 70% of our body is made up of water.i. Water helps to release wastes from the bodies of
living organisms.ii. Water protects living things from diseases.
Q2. Whatmakesourwaterimpure?Ans. ImpuritiesofWater:Unwanted substances present
in water are called impurities. Impurities of water may be soluble (salts and chemicals ), insoluble (sand, pebbles) and suspended (bacteria and litter).
The major sources of impurities of water are human wastes, agricultural chemicals, industrial wastes and run-off from roads.
Q3. Howcanwepreservewater?Ans. HowtoConserveWater: Water is precious. We need to conserve it. We should
not waste it. We can save water by acting following tips.i. Turn off the shower while soaping.ii. Take short showers.iii. While brushing, take water in a tumbler.iv. Don’t wash vegetables and fruits under the
running water.
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v. Check regularly the leakage in water pipes. Get them repaired immediately.
Q4. Writestepsofwastewatertreatment.Ans. WasteWaterTreatment: During waste water treatment, following steps are
taken: 1.PrimaryStage: During this stage, waste water is passed to a big tank.
Here smaller particles present in sewage water settle to the bottom and form sludge.
2.SecondaryTreatment: In the next tank, sewagewater is filtered through
gravel. Here bacteria are also added to the sewage that break down the wastes in it.
3.FinalTreatment: The water is then pumped into open pools. Here air
and sunlight kill harmful bacteria. Chlorine is added to kill remaining germs before releasing the treated water.
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Unit 7StructureofAtom
Section Review I
Q1. What were the ideas of John Dalton about anatom?
Ans. John Dalton said that:i. All water is composed of atoms.ii. Atoms cannot be made or destroyed.iii. Atoms combine to form compounds.
Q2. In what part of an atom is most of its masslocated?
Ans. Most of atom’s mass is located in its nucleus. Protons and neutrons are present in it.
Q3. Definevalency.Ans. The capacity of an atom to combine with an other
atom is called Valency. OR The number of electrons in the outermost shell of an
atom is called its valency.
Section Review II
Q1. Usetheperiodictabletofindthenames,atomicnumbers, and average atomic masses of thefollowingelements:
N,Ca,Kr,WAns. i. N for Nitrogen
Atomic number =7 Atomic mass =14
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ii. Ca for CalciumAtomic number =20 Atomic mass =40
iii. Kr for KryptonAtomic number =36 Atomic mass =84
iv. W for TungstonAtomic number =74 Atomic mass =184
Q2. Writethreeusesofisotopesinmedicines.Ans. i. Iron-59 is used to study spleen.
ii. Iodine-131 and 132 are used in treatment of thyroid glands.
iii. Chromium-51 is used to cure anaemia.Q3. What does the chemical formula of amolecule
show?Ans. The chemical formula of a molecule shows:
i Kinds of elements in the molecule.ii. Number of atoms of each element
Q4. Defineamoleculeandanion.Ans. A molecule is smallest of a matter that can exist. Two and more atoms may combine to make a
molecule. For example, water (H2O) is a molecule in which two hydrogen atoms combine with one oxygen atom.
Ion: Normally an atom is neutal when an atom or a group
of atoms carry charge, it is called an ion. For example Na+, Cl–, OH–, etc are ions.
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Unit Review
Science Words atomic number, noble gases, neutron, anion Fillintheblanksusingthesciencewords.1. Helium (He), neon (Ne), argon (Ar), krypton (Kr),
etc. are ________.2. Negatively charged ion is called _______.3. A _______ is the particle with no charge.4. The number of protons in an atom is called
__________.
Answer: 1. noble gases 2. anion 3. neutron 4. atomic number
MultipleChoiceQuestion Circletheletterofthebestanswer.1. Anatomhasnooverallchargeifitcontainsequal
numberof: (a) electrons and neutrons (b) electrons and protons (c) protons and neutrons (d) positrons and neutrons2. Whichof the followingdescribeswhathappens
when an atom becomes a positive ion with acharge?
(a) The atom gains 2 protons. (b) The atom loses 2 protons. (c) The atom loses 2 electrons. (d) The atom gains 2 electrons.
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3. The correct chemical formula for calciumchlorideis:
(a) CaCl (b) Ca2Cl (c) CaCl2 (d) Ca2Cl2
4. Whosestatementisthis? “Whenelectronsjumpfromoneshelltotheother,
energyisabsorbedorevolved.” (a) James Chadwick (b) Rutherford (c) Niels Bohr (d) John Dalton5. ThenumberofelectronsinN-shellcanbe: (a) 2 (b) 8
(c) 18 (d) 32
Answer: 1. (b) 2. (c) 3.(c) 4. (c) 5. (d)
DetailedAnswerQuestionsQ1. Describethestructureofanatom.Ans. StructureofanAtom: Atoms are very small, but they are made up of even
smaller particles, i.e. electrons,protons and neutrons.i. Electrons: Electrons move around the central
part of the atom (nucleus). They are very light particles. They carry negative charge.
ii. Protons: Protons carry positive charge . They are present in the nucleus. Protons number is equal to the electrons number.
iii. Neutrons:Neutrons have no charge. They are neutral. Neutrons are also present in the nucleus of an atom.
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Q2. Whatisanion?Howionsareformed?Ans. Ion:An atom with positive or negative charge is
called an ion. For examples, sodium ion (Na+), oxide ion (O2–), etc.
Howionsare formed: We know that electrons in atoms carry negative charge. When an atom releases its one or more electrons from its outermost shell, the number of protons increases. It makes a positive ion(cation).
When an atom absorbs electrons in its outermost shell, the number of electrons increases. The atom becomes negatively charged. It makes a negative ion(anion).
Q3. Define the term isotope. Write about theapplicationsofisotopesinthefieldsofmedicineandagriculture.
Ans. Isotopes: The atoms of the same element having same atomic
number but different mass numbers are called isotopes.
Examples:i Hydrogen (H) has three isotopes, i.e. Protium
(11H), Deuterium (2
1H) and Tritium (31H)
ii. Carbon (C) has three isotopes, i.e. 12
6C , 136C , 14
6C ApplicationsofIsotopes: Isotopes are very important in our daily life.
i Bismuth-213 is used to treat cancers.ii. Iron-59is used to anaemia.
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iii. Iodine-131 and 132 are used to treat thyroid disorders.
iv. Nitrogen-15 is used to study plants.v. Carbon-13is used to detect food adultration.
Q4. StateTheLawofConstantCompositionandgiveexamples.
Ans. LawofConstantComposition This law was presented by a French scientist Joseph
Proust. He stated that: “The composition of a compound is always the
same, regardless of how the compound was made or obtained.”
Examplesi. Water can be obtained from many sources such
as river, well, sea, etc. But, its composition is always the same. There are two hydrogen and one oxygen atom in a molecule of water (H2O)
ii. Carbon dioxide (CO2) always consists of one carbon atom and two oxygen atoms.
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Unit 8
ChangesandProcessesAroundUsSection Review I
Q1. What is a change?Ans. When all or a part of a thing becomes different, we
say that it has changed, e.g. boiling of an egg is a change.
Q2. Whatismeantbyaphysicalchange?Ans. When a substance changes its size, colour or form
without becoming a new substance, it is called a physical change.
Example: Freezing of water into ice is a physical change.Q3. Defineachemicalchange.Ans. Chemical change is a change in which a material is
changed into one or more different materials.Q4. Givetwoexamplesofchemicalchanges.Ans. Rusting of iron, souring of milk and burning of
paper, etc are chemical changes.
Section Review II
Q1. Whatishydrogenation?Ans. The addition of hydrogen (H) into vegetable oil to
make fat (Banaspati ghee) is called hydrogenation. This reaction occurs in the presence of nickel.
Q2. Defineplastics.Ans. Plastic and synthetic polymers that can be moulded
into various shapes. Synthetic polymers are made in
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science laboratories.Q3. Givethreeexamplesofnon-reversiblechanges.Ans. 1. Burning of paper 2. Rotting egg 3. Baking of a cake or bread
Unit Review
Science Words corrode, hydrocarbons, fertility, humus, chemical change Fillintheblanksusingthesciencewords.1. Burning of paper is a _______.2. _______ react with oxygen of air and change
chemically.3. Farmers use fertilizers to increase the _______ of
land.4. Metal statues _______ very slowly.5. Chemical fertilizers do not add _______ to the soil.
Answer: 1. chemical change 2. hydrocarbons 3. fertility 4. corrode 5. humus
MultipleChoiceQuestion Circletheletterofthebestanswer.1. Lighteningamatchisanexampleofa: (a) physical change (b) chemical change (c) change in pressure (d) change of colour2. Anexampleofachemicalchangeis: (a) boiling of water (b) evaporation of water (c) burning of paper (d) melting of ice
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3. Theredcolourofaroseturnsbrown.Itisa: (a) physical change (b) chemical change (c) reversible change (d) sudden change4. Whichoneisanon-reversiblechange? (a) rotting egg (b) mixing of salt in water (c) switching on a tube light (d) wetting a dry cloth
Answer: 1. (b) 2. (c) 3.(b) 4. (a)
DetailedAnswerQuestionsQ1. Explain with examples that a chemical change
bringschangeinthepropertiesofasubstance.Ans. A chemical change alters or changes the chemical
properties of a substance. For example:i. Aluminium is a shiny metal and oxygen is a gas.
When both react or undergo a chemical change, a white aluminium oxide is formed.
ii. Iron and oxygen undergo a chemical change and iron oxide or rust is formed.
Q2. Discuss advantages and harmful effects ofchemicalfertilizers.
Ans. Chemicalfertilizers:These are synthetic fertilizers that increase the production of crops.
Advantages:i. Theyareeasytostoreandapplyinfields.ii. They can be used according to the need of the
soil.
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iii. Farmers can harvest two crops per year because of these fertilizers.
Disadvantages:i They do not add humus to the soil.ii. They can deteriorate the structure of soil in case
of improper use.iii. They can add up pollution of land and water.iv. A lot of fossil fuel is used to make these
fertilizers.Q3. Writebriefnoteson: i.Plastics ii.ChangeofvegetableoilintofatAns. i.Plastics: Plastics are synthetic polymers that can be moulded
into various shapes. They are widely used to make soft drink bottles,
jars, toys, machine parts, shopping bags, lenses and parachutes, etc.
PVC, PET, PP and PA are some common names of plastics.
ii.Changeofvegetableoilintofat: Fat or banaspati ghee is formed as a result of chemical
process called hydrogenation. In hydrogenation, hydrogen gas is passed through the vegetable oil in the presence of nickel. Fat or ghee is formed in this process.
Q4. Explain reversible and non-reversible changeswithexamples.
Ans. ReversibleChanges: A change in which the product formed can be sent
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back to its original form is called a reversible change. Examples:
i. Melting of ice into waterii. Switching on a tube lightiii. Mixing of salt into water
Non-ReversibleChanges: A change in which the product formed cannot be sent
back to its original form is called a non-reversible change.
Examples:i. Death of some living bodyii. Burning of paper or woodiii. Rolling of egg or fruit
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Unit 9
TransmissionofHeatSection Review I
Q1. Between which two objects does heat alwaysmove?
Ans. Heat always moves from warmer objects to cooler ones.
Q2. Whatisconductionofheat?Ans. The transfer of heat through a material thing without
any visible movement of particles of matter is called conduction of heat.
Q3. Whyarecookingpotsmadeofmetals?Ans. Metals are good conductor of heat. Heat is necessary
to cook food in cooking pots.Q4. Howdoesconvectionofheatoccur?Ans.Thetransferofheatfromthehotpartofafluidtothe
coolerpartsbythemovementof thefluiditself, iscalled convection.
Q5. Namefourpoorconductorsofheat.Ans. Glass, plastic, wood and paper, etc. are poor
conductors of heat.
Section Review II
Q1. HowdoesheatoftheSunreachtheEarth?Ans. Heat of the sun reaches to Earth by radiation. In
radiation heat needs no medium to travel.Q2. Why do we use woolen clothes and blankets
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duringwinterdays?Ans. Woolen clothes and blankets are insulators. They
slow the transfer of heat. It happens so because wool traps air in it. The air is not a good conductor of heat.
Q3. Whenyousitbesideafire,howdoesheatreachyou?
Ans.Whenwesitbesideafireheatreachesusbyradiation.Theairbetweenfireandusdoesnotgetwarm.
Q4. Howcanthefoodbekepthotforalongerperiod?Ans. To keep the food hot for a longer period, it is kept in
pots with shiny, silvery and smooth surfaces.Q5. Whatistheadvantageofglidingflightforabird?Ans.Theglidingflighthelps thebird tosave itsenergy
duringlongflight.Birdslikeeagles,vultures,hawks,etcglideonaircurrents.Duringsuchflight,theydonot move their wings.
Q6. Why are the cooling fins at the back of yourrefrigeratorpaintedblack?
Ans.These fins help the refrigerator to radiate its heatquickly to the surroundings.
Unit Review
Science Words fluid,convection,conduction,heatenergy Fillintheblanksusingsciencewords.1. Thermos bottle use air or a vacuum to slow the
transfer of heat by _______.2. Radiation is the fastest way to transfer ________.3. _______ takes place more readily in gases than in
liquids.
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4. Anymaterialthatflowsiscalleda________.
Answer: 1. conduction 2. heat energy 3. convection 4.fluid
MultipleChoiceQuestion Circletheletterofthebestanswer.1. Heatenergytravelsthroughametalspooninhot
teamostlyby: (a) radiation (b) conduction
(c) convection (d) insulation2. What is the name given to any material that
transfersheatenergyeasily? (a) thermal (b) metal
(c) insulator (d) conductor3. Landbreezesandseabreezesblowdueto: (a) conduction of heat (b) convection of heat (c) radiation of heat (d) emission of heat4. How is the transfer of heat slowed down in a
thermosbottle? (a) by the use of a vacuum (b) by the use of paper (c) by the use of a metal sheet (d) by the use of wood5. Whattypeofenergytransferproducesweather? (a) radiation (b) convection
(c) conduction (d) atmospheric
Answer: 1. (b) 2. (d) 3.(b) 4. (a) 5. (b)
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DetailedAnswerQuestionsQ1. Whatisconvection?Howdoesitoccur?Ans. Convection:The transfer of heat from the hot part
of fluid (liquid organs) to the cooler parts by themovementofthefluiditself,iscalledconvection.
HowdoesConvectionoccur:When heat is given to a fluid, its particles began tomove fast. Theseparticles move to other parts of fluid. To fill thespace, cooler particles come to the place of the heated particles. The process continues and whole thefluidgetshot.
Q2. Write everyday applications of conduction ofheat.
Ans. ApplicationsofConductionofHeat:Conduction of heat is very important for us:i. Cooling utensils, electric kettles, irons, boilers
and soldering irons are made of metals to conduct heat quickly.
ii. The handles of above given things are made of wood or plastic. Wood and plastic are insulators. They do not conduct heat.
iii. Ice is covered with jute rugs to reduce melting of ice. Jute is an insulator.
iv. We use woolen clothes and blankets during cool winter days to reduce the transfer of heat.
Q3. Writeanoteonathermosbottle.Ans. ThermosBottle:A thermos bottle is also called a
vacuumflask.Itisusedtokeepthingshotorcoldfor
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a longer time. The thermos bottle reduces transfer of heat by conduction, convection and radiation.
A thermos bottle consists of two thin glass bottles, one inside the other.
Air between the walls of two bottles is removed to create vacuum. This vacuum reduces the transfer of heat by conduction and convection. The shiny walls of glass bottles reduce the transfer of heat by radiation.
Q4. Writebriefnoteson: i.Landbreezesandseabreezes ii.GlidingaflightofbirdsAns. i. LandbreezesandSeaBreezes:Land and sea
breezes are caused by convection of heat. The land heats up fast during the day as compared to the sea. The hot air rises, the cool breeze from the sea blows towards the land to take the place of rising hot air.
ii.Glidingflightofbirds:Convection currents also help some birds to reduce the use of energy during theirflight.Eagles,hawks,vulturesandkites,etcdonotmove theirwingswhile flying on piles of air.Theyenjoytheirglidingflightduetoconvectionofheat.
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Unit 10
RefractionandDispersionofLight
Section Review I
Q1. Whatisrefractionoflight?Ans. When a ray of light enters into an other medium at
an angle, the change in speed causes it to bend. This bending of light is called refraction of light.
Q2. What is refractive index?Ans. When speed of light is divided by the speed of light
in a medium, the refractive index of that medium is obtained. For example, the refractive index of glass is 1.5.
Q3. Definethedispersionoflight.Ans. The splitting of white light into its component
colours is called dispersion of light.Q4. Listthesevencoloursofwhitelightdispersedby
aprism.Ans. These colours of light are: i. violet ii. Indigo iii. blue iv. green v. orange vi. yellow vii. red
Section Review II
Q1. Whatismeantbytotalinternalreflection?Ans. When light passes from a denser medium to a rare
medium (air), it bends away from the normal. But
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when the angle of incidence (i) is greater then the criticalangle (c), the light rays reflect in thesamedenser medium. This phenomenon is called total internalreflection.
∠i˃∠cQ2. Brieflydescribewhyyousometimesseearainbow
duringarainshowerorshortlyafterward.Ans. When white light from the sun shines through tiny
rain drops, They act like prisms. They refract and reflectlightandseparateitintocolours.Inthisway,a rainbow is formed.
Q3. Whydoweseethepetalsofaroseasredandtheleavesasgreen?
Ans. The colour of an object is the colour of light it reflects.
Thepetalsofarosereflectredcolourandlookred.Theleavesofarosereflectgreencolouroflightandlook green.
Q4. Whataretheprimarypigmentcolours?Ans. Cyan, yellow and magenta are the primary pigment
colours.Q5. Explain the scene of seeing water on the road
ahead,whiletravellingonahot,sunnyday.Ans. We see the scene of water on the road ahead in
summer, it is a mirage. A mirage is an image of some distant object which appears to us due to the refraction and total internal reflection of lightthrough cold and warm layers of air.
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Unit Review
Science Words prism, refraction, critical angle, incident ray Fillintheblanksusingthesciencewords.1. The bending of light, when it enters from one
medium to another is called ______.2. The light ray that enters the new medium, is called
an _______.3. The angle of incidence at which maximum refraction
occurs is called the ________.4. A _______ is a transparent wedge-shaped block of
glass.
Answer: 1. refraction 2. incident ray 3. critical angle 4. prism
MultipleChoiceQuestion Circletheletterofthebestanswer.1. Refractiveindexofglassis: (a) 1.47 (b) 2.42
(c) 1.5 (d) 1.332. The splitting of white light into its component
coloursiscalled: (a)dispersionoflight (b)reflectionoflight (c)interferenceoflight (d)irregularreflection3. Weseeamirageduetothe: (a)reflectionoflight (b)totalinternalreflection (c) dispersion of light (d) spectrum of light
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4. When all the colours of light are reflected intooureyes,theobjectappears:
(a) black (b) red (c) green (d) white
5. Bymixingamagentaandcyanpigmentswecanproducethecolour:
(a) blue (b) green (c) white (d) red
Answer: 1. (c) 2. (a) 3.(b) 4. (d) 5. (a)
DetailedAnswerQuestionsQ1. Verify the “Laws of Refraction” through an
activity.Ans. The Laws of Refraction There are two laws of refraction:
i. The incidence ray, the refracted ray and the normal act the point of incidence, all lie in the same plane.
ii. The ratio of the sine of the angle of incidence to the sine of the angle of refraction is a constant.
Thislawcanbyverifiedbyanactivity. Activity: Toverifythelawsofrefractionusingaglassslab youwillneed: a glass slab,a drawing board,drawing pins,white
sheet of paper,common pins,geometry box Procedure:● Fix awhite sheet of paper on the drawing board,
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using drawing pins.● Place a glass slab in themiddle of the paper and
draw its boundary PQRS.● FixtwopinsAandBonthepaperinastraightline
that make an angle with the slab.● Get to the other side of the slab and look at the
images of pins A and B through it.● FixtwomorepinsCandDonthissideinthelineof
images of A and B.● Remove the slab and the pins.Draw small circles
around the pin points.● JoinAandBtothePQatpointM.● JoinCandDtotheSR
at point L.● NowjoinMandL.● Drawperpendicularor
normal FG at point M.● ABistheincidentray● MListherefractedray Verify the laws of
refraction using the diagram.Q2. What is the total internal reflection?Explain it
withanexample.Ans. Total Internal Reflection: When light passes a
denser medium (glass or water) to a rare medium (air), it bends away from normal. But when the angle of incidence (∠i) is greater than the critical angle (∠c), the light rays reflect in the same denser medium, this phenomenon is called total internal reflection.
A
B
CD
G
M
F
L
P Q
RS
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ConditionsoftotalInternalReflectioni. Light passes from a denser medium to a rare
medium.ii. The angle of incidence of all rays is greater
than the critical angle ∠i˃∠c Example: On hot, summer days, the air close to the
roads get warmer than upper cold layers. Cold air is denser than the warm air. When light from the sun passes from cold layers of air to the warmer layers of air, they refract and also totally reflect. The person traveling on the road, looks water on the road ahead. It is a mirage which is seen due to total internal reflection of light.
Q3. Whatisdispersionoflight?Whydoeswhitelightgetdispersed?
Ans. DispersionofLight Sunlight is a combination of different colours. When
it is passed through prism, each colour of light refracts at different angle. We see seven colours of white light after passing through a prism.
This splitting of white light into its component colours is called the dispersion of light.
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Unit 11
WavesandSoundSection Review I
Q1. Defineawave.Ans. The disturbance which transfers energy from one
place to the other is called a wave.Q2. Sketch a transverse wave and label a crest, a
trough,awavelength,andamplitude.Ans.
crest
wave length trough
amplitude
Q3. Listthefourbasicpropertiesofwaves.Ans. These properties are: i. Amplitude ii. Wave length iii. Frequency iv. SpeedQ4. Howarethespeed,wavelength,andfrequencyof
awaverelated?Ans. This equation shows the relationship of the speed,
wavelength and frequency of a wave. Speed = wavelength × frequency We can calculate any one of the three values if we
know the other two.
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Section Review II
Q1. Whattypeofwavesaresoundwaves?Ans. Sound waves are longitudinal waves.Q2. Whatmakessomesoundslouderthanothers?Ans. Amplitude of sound wave makes some sounds
louder than others. Greater the amplitude, louder the sound is.
Q3. Whatistherelationshipbetweenfrequencyandpitch?
Ans. Pitch and frequency of a sound are directly related to each other. The higher the frequency, the higher the pitch is.
Q4. Explainbriefly,howcanamusicalsoundshatteraglass.
Ans. Some musical instruments can produce sounds whose frequency may match the natural frequency of a crystal glass. If both the frequencies match, the amplitude increases that shatters the glass.
Q5. Whatistheunitoftheloudnessofasound?Ans. The loudness of a sound is measured in units called
decibels (dB). The sound in an average home is 40-50 dB.
Q6. Defineultrasoundandinfrasound.Ans. Sound waves whose frequencies are above the
normal audible human range (20,000 Hz), are called ultrasound.
The sound waves which have frequencies below 20 Hz are called infrasound.
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Unit Review
Science Words compression, vibration, medium, speed, musical Fillintheblanksusingthesciencewords.1. The sound depends on the size and shape of the
_________.2. The distance a wave covers or travels in one second
is called its _________.3. A _________ and a rarefaction combine to form a
longitudinal wave.4. A material thing through which a wave travels is
called a _________.5. A _________ is a repeated to-and-fro or up-and-
down motion.
Answer: 1. musical instrument 2. speed 3. compression 4. medium 5. vibration
MultipleChoiceQuestion Circletheletterofthebestanswer.1. Thedistancebetweenonecrestandthenextcrest
isthewave’s: (a) amplitude (b) wavelength
(c) frequency (d) speed2. Asoundwaveisa: (a) transverse wave (b) longitudinal wave
(c) reverse wave (d) standing wave
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3. Hittinganobjectharderwillmakethevolume: (a) softer (b) the same
(c) lower (d) louder4. Thelowestpartsofatransversewavearecalled: (a) crests (b) compressions
(c) rarefactions (d) troughs5. Soundwavestravelthequicklythrough: (a) solids (b) gases
(c) air (d) liquidsAnswer: 1. (b) 2. (b) 3.(d) 4. (d)
5. (a)
Detailed-AnswerQuestionQ1. Describethebasicpropertiesofwaves.Ans. BasicPropertiesofWaves The basic properties of waves are: 1. Amplitude 2. Wavelength 3. Frequency 4. Speed 1.Amplitude:The amplitude of a transverse wave
is the distance between a crest or trough and rest position.
In case of longitudinal waves, the amplitude is a measureofhowcompressedorrarefiedthemediumbecomes.
2.Wavelength:The distance between two adjacent crests or troughs is called wavelength.
In case of a longitudinal wave this distance is between two adjacent compressions or rarefactions.
3.Frequency:The number of waves that passes a given point in one second is called the frequency of
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a wave. 4.Speed:The distance a wave covers in one second
is called its speed.Q2. Compare a transversewave and a longitudinal
wave.Ans. TypesofWaves:Waves are of two types: 1. Transverse Waves 2. Longitudinal Waves 1.TransverseWaves:A wave in which particles of
the medium move at right angle to the path of the wave, is called a transverse waves.
Trough
crest
2.LongitudinalWaves:A wave in which particles of the medium move back and forth, parallel to the path of the wave is called a longitudinal wave.
Example Sound waves produced in air are longitudinal waves.
crest
trough
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Q3. Describeloudnessandpitchofthesound.Ans. 1.Loudness:Loudness is related to the amplitude of
the sound wave. A sound wave of greater amplitude sounds louder. The unit of loudness is decibels (dB).
2.Pitch:Pitch is the highness or lowness of a sound. Pitch depends upon the frequency of the sound. The higher the frequency, the higher the pitch is. Its unit is hertz (Hz).
Q4. Writebriefnoteson: (a)Audiblefrequencyrange (b)HearinglossAns. Audible frequency range: The range of sound
frequencies that can be heard by an animal or humans is called audible frequency range. We can hear sounds of 20---20,000 Hz. It is the audible frequency range of humans.
HearingLoss:Some people suffer hearing loss as a result of injury, infection, or aging. It is the inability of listening sound.
CausesofHearingLossi A head injury can disconnect the three bones of
middle ear.ii. An injury can puncture the ear drum.iii. Viral or bacterial infection can cause hearing
loss.iv. In old people this ability can be lost.
Treatment: Many people use hearing aids to improve their hearing ability.
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Unit 12Electricity
Section Review I
Q1. Whatisanelectriccurrent?Ans.Theflowofelectronsthroughaconductoriscalled
electriccurrent. Itflows from thenegativepoleofthe source (battery) to the positive pole.
Q2. Defineacircuit.Ans.The complete path along which electrons flow is
called an electric circuit. It may be parallel or series.Q3. Howmanypartsdoesacircuitconsistof?Ans. A circuit consists of the following three parts.
i. source of electricityii. connecting metal wiresiii. device that run by electricity
Q4. Whathappens to thebulbs ina seriescircuit ifoneofthebulbsburnsout?
Ans. In this case all the bulbs will stop glowing because:● Abreakinanybranchoftheseriescircuitstopsthe
flowofcurrentinallbulbs.Q5. Whichcircuitwouldyouliketobeinyourhouse,
aseriesoraparallel?Ans. I would like a parallel circuit to be in my house
because:● Abreakinmybranchofthecircuitstopsthecurrent
flowingthroughthatbranch.Alltheotherbranchescontinue their working.
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Section Review II
Q1. Whatispotentialdifference?Ans. The difference of electric potential between two
poles of a battery or source is called the potential difference. This potential difference causes the currenttoflow.
Q2. StateOhm’sLaw.Ans. This law states that “ resistance is equal to the voltage
(potential difference) divided by the current.
Resistance (Ohm) = Voltage (volts)Current (amperes)
Q3. Howareresistance,voltage,andelectriccurrentrelated?
Ans. A scientist Simon Ohm discovered this relationship. According to him;
Resistance = VoltageCurrent
Q4. Findthepowerproducedby1.8amperecurrentatavoltageof120V.
Ans. Current = 1.8 amperes Voltage = 120 v Power = ? We know that Power = Voltage × current Power = 120 × 1.8 Power = 216 wattsQ5. Definekilowatthour.Ans. When 1000 watts are used in one hour, the power is
called kilo watt hour (KWh)
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Q6. WhatisthefunctionofanELCB(earthleakagecircuitbreaker)?
Ans. An ELCB is used to turn off the power when the current flowing through the earth wire exceeds alimit. It prevents an electric shock.
Unit Review
Science Words earth wires, Ohm, series circuit, electrical power,
electric current Fillintheblanksusingthesciencewords.1. In a __________, there is only one path for the
currenttoflow.2. One _________ is the resistance of a wire when one
amperecurrentflowsacrossitunderonevolt.3. Watt is the unit for _________.4. Theflowofelectronsthroughaconductoriscalled
_________.5. _________ protect people from electric shocks.
Answer: 1. series circuit 2. Ohm 3. electrical power 4. electric current 5. earth wires
MultipleChoiceQuestion Circletheletterofthebestanswer.1. When there are several paths for a current to
take,thecircuitiscalled: (a) series circuit (b) parallel circuit (c) incomplete circuit (d) full circuit
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2. “Theresistanceisequaltothevoltagedividedbythecurrent”.Thislawwaspresentedby:
(a) George Ohm (b) George Samual (c) Alssandro Volta (d) James Watt
3. Aresistancechangestheelectricalenergyinto: (a) chemical energy (b) heat
(c) sound (d) nuclear energy4. Theenergysourcecanbe: (a) a battery (b) a light bulb
(c) a metal wire (d) an electric motor5. The electrical energy used in our house is
measuredinunitsof: (a) kilowatt-hours (b) amperes (c) kilowatts (d)watt-hour
Answer: 1. (b) 2. (a) 3.(b) 4. (a) 5. (a)
Detailed-AnswerQuestionQ1. Describeseriesandparallelcircuits,
disadvantagesofaseriescircuitandadvantagesofaparallelcircuit.
Ans. There are two important kinds of circuits i.e. series circuits and parallel circuits.
1.SeriesCircuits If all the parts of a circuit are joined one after another,
it is called a series circuit. It provides only one path forthecurrenttoflow.
Disadvantage:There is only one path for the current to take. A break in any part of the circuit stops the flowofcurrentinthewholecircuit.
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2.ParallelCircuit If different parts of a circuit are on separate branches,
it is called a parallel circuit. There are several paths for the current to take.
Advantage: There are several paths in a parallel circuit. So, a break in any branch stops the flowof current only in that branch. All other branches continue their working.
Q2. Explain heating and chemical effects of thecurrent.
Ans. 1.HeatingEffectsoftheCurrent When electricity passes through wires, some of its
part heats the wires. High resistance causes great amount of heat to produce. When a wire becomes very hot, it produces light. We observe heating effects of current in irons, toasters and electric kettles.
2.ChemicalEffectsoftheCurrent An electric current can chemically affect the
materials.Whencurrentflowsthroughasolution,itcan break the solution into its components. This process is called electrolysis.
Electrolysis can be observed in the process of electroplating. In this process, electricity is used to cover one metal with another. The rims of our bikes are nickel-plated.
Q3. Howdoelectronsflow?Explain.Ans.Thecurrentorelectronsflowsinwiresjustlikethe
flowofwaterinapipe.Bothflowfromaplaceofa higher potential to the place of a lower potential. The difference of electric potentials between two
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polesofabatterycausestheelectronstoflow.Q4. Writenoteson: i. Resistance ii. ElectricPower iii. MCBs iv. ELCBAns. i. Resistance: The tendency of a metal wire to
oppose theflowof an electric current is called itsresistance. IT depends on:
length of the wire thickness of the wire type of metal A long wire has more resistance than the short one.
Thin wires have more resistance. The resistance of copper is more than that of silver.
ii.ElectricPower:The rate at which a device uses electrical energy is called its electric power. Its unit is watt.
Power = voltage × current iii.MCBs:MCBs or miniature circuit breakers are
used to break the circuit by tripping, when a current more than usual. This switch can easily be reset.
iv.ELCB:An ELCB or earth leakage circuit breaker is also used in electric circuits. It quickly turns off the power when the current flowing through theearth wire exceeds a limit. An ELCB can also be easily reset.
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Unit 13ExploringtheSpace
Section Review I
Q1. Isayellowstar,suchasthesun,hotterorcoolerthan an orange star?
Ans. A yellow star, such as the sun is hotter than an orange star. The temperature of the sun ( a yellow star) is 6,000°C. The temperature of Arcturus (an orange star) is 4,100°C.
Q2. Wherearestarsbornintheuniverse?Ans. Stars born in nebulae. A nebula is a great cloud of
gases and dust. During the spinning movement of a nebula, gases and dust are packed into a hot ball that later becomes a star.
Q3. Whatissupernova?Ans. During the life cycle of a massive star, a supergiant
becomes so dense that it cannot bear the pressure of outer layers. The outer layers crash inward with a tremendous explosion called supernova.
Q4. Onwhich factors does the brightness of a stardepend?
Ans. The brightness of a star depends on:i distance of the star from the Earthii. amount of energy the star emits.
Q5. Whatisalight-year?Ans. A light-year is the distance that light covers in one
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year with a speed of 300,000 kilometres per second ( speed of light).
Section Review II
Q1. Defineagalaxy.Ans. A galaxy is a very large group of stars, nabulae,
gases, dust and planets. It may consist of billions of stars. Milkyway, Andromeda, etc. are galaxies.
Q2. Whatisaconstellation?Ans.A cluster of stars with a definite pattern is called
constellation. Big Dipper, Leo and Scorpius, etc are constellations.
Q3. WhenwasHubbleSpaceTelescopelaunched?Ans. Scientists launched this huge telescope in space on
April 24, 1990.Q4. Nameatleastfiveconstellationsseeninthesky.Ans. The Great Bear, Big Dipper, Little Diper, Leo and
Scorpius are a few constellations.Q5. Whatgalaxyisoursunbelongto?Ans. Our sun belongs to the Milkyway galaxy.
Unit Review
Science Words black dwarf, galaxy, Hubble Space Telescope,
refracting telescope, cosmology Fillintheblanksusingthesciencewords.1. A large group of stars, gases, and dust is a _________.2. The last stage of a low-mass star’s life is called
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_________.3. A _________ focuses light from a distant object to a
pointandmagnifiestheimage.4. The scientific studyof theuniverse, its origin and
development is called _________.5. The _________ can see objects in space more clearly
than any other telescope.
Answer: 1. galaxy 2. black dwarf 3.refracting telescope 4. cosmology 5. Hubble Space Telescope
MultipleChoiceQuestion
Circletheletterofthebestanswer.1. Stardistancesareusuallymeasuredin: (a) meters (b) kilometers
(c) light-years (d) yards2. Polaris(NorthStar)isintheconstellation: (a) Ursa Minor (b) Orion
(c) Draco (d) Taurus3. Betelgeuseisa: (a) red star (b) yellow star
(c) blue star (d) orange star4. Peoplehaveusedastartofindthedirection: (a) Polaris (b) Lyra
(c) Antares (d) Regulus5. Ourneighbouringgalaxyisnamedas: (a) Cepheus (b) Andromeda (c) Canis Major (d) Taurus
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Answer: 1. (c) 2. (a) 3.(a) 4. (a) 5. (b)
Detailed-AnswerQuestionQ1. ExplaintheBigBangtheoryoftheoriginofthe
universe.Ans. TheBigBangTheory It is a famous theory that tries to explain the origin
of our universe. About 10 to 20 billion years ago, the whole universe was in the form of one giant fireball. Then, a tremendous explosion started theexpansion of the universe. This explosion is known as the Big Bang. The Big Bang scattered the matter in all directions, with the passage of time stars and galaxies came into existance.
Q2. Describethelifecycleofalow-massstar.Ans. LifeCycleofaLow-massStar A star is also born, changes and then dies. Birth of a Star Stars born in nebulae. A nebula is a great cloud of
gases and dust. During the spinning movement, gases and dust are packed into a huge ball of matter. It is called a protostar. Protostar then becomes a star that emits heat and light.
DeathofaStar Stars continuously release energy. Our Sun is a star
of low-mass. It has been emitting energy far fivebillion years. After next 5 billion years, the hydrogen gas in the core of sun will have been used up. The sun will start to collapse and then its core will burst.
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It will be a red giant. With the passage of time this red giant will become a white dwarf and in the end a black dwarf. This is the last stage of low-mass star’s life.
Q3. Describethethreemaintypesofgalaxies.Ans. TypesofGalaxies A galaxy is a very large group of stars. There are
three main types of galaxies.1. Spiral Galaxies: A spiral galaxy has a flat
disk like shape with a bulge in the centre. Such galaxy has a few or many arms. The Milkyway and Andromeda are spiral galaxies.
2. Elliptical Galaxies: These are oval shaped galaxies. It looks like a foot ball. They do not rotate as spiral galaxies rotate around their axis.
3. Irregular Galaxies: These galaxies have no definiteshape.
Q4. Writenoteson: i. Arefractingtelescope ii.SafetymethodstousewhenobservingthesunAns.i.ARefractingTelescope A refracting telescope focuses light from a distant
object to a point and latermagnifies the image toform a better view. A simple refracting telescope consists of two convex lenses:i. Objective lens of large focal lengthii. Eye-piece of small focal length
Theselensesarefixedonseparatetubesthateasilyslide into one another.
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ii.SafetyTipsforObservingtheSun: Looking at the sun without any safety measure is
dangerous. So:i. DonotlookdirectlyattheSun.Useafilterwith
binocular or a telescope.ii. To observe solar eclipse, make its image on a
white screen or card board.iii. Use special welder’s glasses or Mylar glasses to
safely observe the solar eclipse.
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Model Paper No-11stTerm(Units1-4)
TimeAllowed:2:00Hours TotalMarks:100Part-A(MultipleChoiceQuestions)• Fifteen(15)MultipleChoiceQuestions(MCQs) aregiveninthispart.Allquestionscarryequal marks. (15×2)1. Ahypothesisistestedbya(n): (a) conclusion (b) data (c) experiment (d) inference2. Who studies plants, animals, microorganisms
andtheirbehaviours? (a) a chemist (b) a biologist (c) a geologist (d) a physicist3. Degree Celsius (°C) or Degree Fahrenheit (°F)
areunitsof: (a) time (b) volume (c) length (d) temperature4. Waterisabsorbedinthe: (a) liver (b) oesophagus (c) small intestine (d) large intestine5. Airismoistened,filteredandwarmedinthe: (a) larynx (b) nasal cavity (c) pharynx (d) trachea6. Exchangeofgasesoccursbetweenthe________
andcapillaries. (a) alveoli (b) bronchioles (c) bronchi (d) trachea 7. Bloodiscarriedawayfromtheheatin:
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(a) arteries (b) veins (c) nerves (d) ureters8. Wheredoestheexchangeoffood,oxygenand
wastesoccurin? (a) arteries (b) veins (c) capillaries (d) lymph vessels9. Movementofmaterialsinaplantfromaregion
of lower concentration to the region of higherconcentrationbytheuseofenergyiscalled:
(a) osmosis (b) transpiration (c) active transport (d) diffusion10. Whathelpsprotectseeds? (a) fruit (b) wind (c) bees (d) cotyledon11. Whenabeelandsonaflower,itbrushesagainst: (a) seeds (b) cones (c) pollen grains (d) fruit12. Colourfulflowersareusuallypollinatedby: (a) clothing (b) wind (c) birds (d) insects13. Theribcage_________whenyouexhale. (a) moves up (b) moves out (c) moves down (d) stays the same14. Which tissue of a plant transports water and
mineralsfromrootstoleaves? (a) xylem (b) phloem (c) bark (d) mesophyll15. The________containsfoodfortheembryo: (a) stigma (b) endosperm (c) pollen grains (d) root
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Part-B(OpenEndedQuestions) Marks:70Q.1.Fillintheblanks. (5×2)1. Kilogram is the unit of ______.2. The ______ is a large tube that runs from the mouth
to the stomach.3. ______ is the movement of materials from a region
of higher concentration to the region of lower concentration.
4. The ______ protects a seed.5. Most grasses depend upon ______ for their
pollination.Q.2 Answerthefollowingquestionsinshort. (10×3)1. What is science?2. Writethestagesofthescientificmethod?3. What is digestion?4. What are the symptoms of constipation?5. What is pericardium?6. Name the parts of blood.7. What is pollination?8. Definefertilization.9. How can you avoid heart diseases?10. What is transpiration?Q.3.Answerthequestionsindetail.(anyfive) (5×6)1. Describedifferentstagesofthescientificmethod.2. Explain the process of digestion of food in the mouth
and the stomach.3. Describe the structure of human heart.4. Write a brief note on transplantation.5. Write a note on fruit.6. Explain the human respiratory system.7. Write a brief note on diabetes.
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Model Paper No-21stTerm(Units1-4)
TimeAllowed:2:00Hours TotalMarks:100Part-A(MultipleChoiceQuestions)• Fifteen(15)MultipleChoiceQuestions(MCQs) aregiveninthispart.Allquestionscarryequal marks. (15×2)1. DegreeCelsius(°C)orDegreeFahrenheit(°F)
areunitsof: (a) time (b) volume (c) length (d) temperature2. Whoisthefounderofmodernalgebra? (a) Newton (b) Al-Dinawari (c) Al- Khwarizmi (d) Al-Razi3. Oxygengaswasdiscoveredby: (a) Charles Darwin (b) Joseph Proust (c) Marie Curie (d) Joseph Priestly4. Exchangeofgasesoccursbetweenthe________
andcapillaries. (a) alveoli (b) bronchioles (c) bronchi (d) trachea 5. Theribcage_________whenyouexhale. (a) moves up (b) moves out (c) moves down (d) stays the same6. Theprocessof___________occursinalong,
muscularandcoiledtubecalledalimentarycanal.
(a) respiration (b) reproduction (c)digestion (d)classification7. Movementofmaterialsinaplantfromaregion
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oflowerconcentrationtotheregionofhigherconcentrationbytheuseofenergyiscalled:
(a) osmosis (b) transpiration (c) active transport (d) diffusion8. Which tissue of a plant transports water and
mineralsfromrootstoleaves? (a) xylem (b) phloem (c) bark (d) mesophyll9. Thecellsthatcontainhaemoglobinare: (a) platelets (b) bone cells (c) white blood cells (d) red blood cells10. Colourfulflowersareusuallypollinatedby: (a) clothing (b) wind (c) birds (d) insects11. The________containsfoodfortheembryo: (a) stigma (b) endosperm (c) pollen grains (d) root12. Theembryonicleavesofanembryoare: (a) root hairs (b) radicles (c) plumules (d) cotyledons13. Whostudiesplants,animals,microorganisms
andtheirbehaviours? (a) a chemist (b) a biologist (c) a geologist (d) a physicist14. Airismoistened,filteredandwarmedinthe: (a) larynx (b) nasal cavity (c) pharynx (d) trachea15. Wheredoestheexchangeoffood,oxygenand
wastesoccur? (a) in arteries (b) in veins (c) in capillaries (d) in lymph vessels
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Part-B(OpenEndedQuestions) Marks:70Q.1.Fillintheblanks. (5×2)1. On the basis of analysis of the recorded data, a
scientist comes to a ________.2. Thefirstpartofsmallintestineiscalled_________.3. The liquid part of our blood is called ________.4. Ovary contains ________ which develop into seeds.5. Kilogram is the unit of _______________.Q.2 Answerthefollowingquestioninshort. (10×3)1. Definechemistry.2. Who discovered radioactivity?3. What is respiration?4. What causes air to move in and out of the lungs?5. What is the function of haemoglobin in red blood
cells?6. What is asthma?7. Which is the most important part of a seed?8. What is osmosis?9. What are the symptoms of constipation?10. Name the parts of blood.Q.3.Answerthequestionsindetail.(anyfive) (5×6)1. Writebrieflyaboutthemeasurementoftime,length,
mans, temperature and volume.2. Describe the digestion of carbohydrates and proteins.3. List and describe the four components of blood and
their functions.4. Describe the structure of a seed.5. Describedifferentstagesofthescientificmethod.6. Explain the process of digestion of food in the mouth
and the stomach.7. Describe the structure of human heart.
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Model Paper No-31stTerm(Units1-4)
TimeAllowed:2:00Hours TotalMarks:100Part-A(MultipleChoiceQuestions)• Fifteen(15)MultipleChoiceQuestions(MCQs) aregiveninthispart.Allquestionscarryequal marks. (15×2)1. Thestudyofforce,energyandmotionofobjects
iscalled: (a) chemistry (b) physics (c) biology (d) mathematics2. Oxygengaswasdiscoveredby: (a) Charles Darwin (b) Joseph Proust (c) Marie Curie (d) Joseph Priestly3. Ahypothesisistestedbya(n): (a) conclusion (b) data (c) experiment (d) inference4. Itisdonebyoxygengaswhichhelpsinreleasing
energyfromfood. (a) breathing (b) digestion (c) respiration (d) reproduction5. Theprocessof___________occursinalong,
muscularandcoiledtubecalledalimentarycanal.
(a) respiration (b) reproduction (c)digestion (d)classification6. Waterisabsorbedinthe: (a) liver (b) esophagus (c) small intestine (d) large intestine
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7. Itisadisorderoflungs,whichcausesattacksofwheezing,shortnessofbreathing,chesttightnessandcoughing.
(a) diabetes (b) asthma (c) malaria (d) diarrhea8. Thecellsthatcontainhemoglobinare: (a) platelets (b) bone cells (c) white blood cells (d) red blood cells9. Bloodiscarriedawayfromtheheatin: (a) arteries (b) veins (c) nerves (d) ureters10. Insidethepetals,arethemalepartsofaflower
called: (a) carpel (b) stamens (c) ovary (d) stigma11. Theembryonicleavesofanembryoare: (a) root hairs (b) radicals (c) plumules (d) cotyledons12. Whathelpsprotectseeds? (a) fruit (b) wind (c) bees (d) cotyledon13. Colourfulflowersareusuallypollinatedby: (a) clothing (b) wind (c) birds (d) insects14. Movementofmaterialsinaplantfromaregion
oflowerconcentrationtotheregionofhigherconcentrationbytheuseofenergyiscalled:
(a) osmosis (b) transpiration (c) active transport (d) diffusion
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15. Exchangeofgasesoccursbetweenthe________andcapillaries.
(a) alveoli (b) bronchioles (c) bronchi (d) tracheaPart-B(OpenEndedQuestions) Marks:70Q.1.Fillintheblanks. (5×2)1. A mathematician uses the method of __________ to
solve problems.2. The dome-shaped muscle at the bottom of our chest
is called ________.3 Diabetes is a disorder of __________.4. Most grasses depend upon _______ for their
pollination.5. The ______________ protects a seed.Q.2 Answerthequestioninshort. (10×3)1. Who is the founder of modern algebra?2. What is science?3. Which blood vessels in the lungs help your body
take in and give of gases?4. What is digestion?5. How can you avoid heart diseases?6. What is pericardium?7. What is transpiration?8. What is pollination?9. Writethestagesofthescientificmethod?10. Definefertilization.Q.3.Answerthequestionsindetail.(anyfive)(5×6)1. Write contributions of the following scientists:2. Explain the human respiratory system.3. Write brief note on diabetes.
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4. Write a note on fruit.5. Write brief note on transplantation.6. Explain the process of digestion of food in the mouth
and the stomach.7. Describe the structure of a seed.
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Model Paper No-41stTerm(Units1-4)
TimeAllowed:2:00Hours TotalMarks:100Part-A(MultipleChoiceQuestions)• Fifteen(15)MultipleChoiceQuestions(MCQs) aregiveninthispart.Allquestionscarryequal marks. (15×2)1. Whoisthefounderofmodernalgebra? (a) Newton (b) Al-Dinawari (c) Al- Khwarizmi (d) Al-Razi2. Ahypothesisistestedbya(n): (a) conclusion (b) data (c) experiment (d) inference3. Thestudyofforce,energyandmotionofobjects
iscalled: (a) chemistry (b) physics (c) biology (d) mathematics4. Theribcage_________whenyouexhale. (a) moves up (b) moves out (c) moves down (d) stays the same5. Waterisabsorbedinthe: (a) liver (b) esophagus (c) small intestine (d) large intestine6. Itisdonebyoxygengaswhichhelpsinreleasing
energyfromfood. (a) breathing (b) digestion (c) respiration (d) reproduction7. Whichtissueofaplanttransportswaterand
mineralsfromrootstoleaves? (a) xylem (b) phloem
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(c) bark (d) mesophyll8. Bloodiscarriedawayfromtheheatin: (a) arteries (b) veins (c) nerves (d) ureters9. Itisadisorderoflungs,whichcausesattacksof
wheezing,shortnessofbreathing,chesttightnessandcoughing.
(a) diabetes (b) asthma (c) malaria (d) diarrhea10. The________containsfoodfortheembryo: (a) stigma (b) endosperm (c) pollen grains (d) root11. Whathelpsprotectseeds? (a) fruit (b) wind (c) bees (d) cotyledon12. Insidethepetals,arethemalepartsofaflower
called: (a) carpel (b) stamens (c) ovary (d) stigma13. Whenabeelandsonaflower,itbrushesagainst: (a) seeds (b) cones (c) pollen grains (d) fruit14. Where does the exchange of food, oxygen and
wastesoccur? (a) in arteries (b) in veins (c) in capillaries (d) in lymph vessels15. Airismoistened,filteredandwarmedinthe: (a) larynx (b) nasal cavity (c) pharynx (d) trachea
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Part-B(OpenEndedQuestions) Marks:70Q.1.Fillintheblanks. (5×2)1. The ___________ is a large tube that suns from the
mouth to the stomach.2. On the basis of analysis of the recorded data, a
scientist comes to a ________.3. ___________ is the movement of materials from a
region of higher concentration to the region of lower concentration.
4. The liquid part of our blood is called ________.5. Ovary contains __________ which develop into
seeds.Q.2 Answerthefollowingquestioninshort. (10×3)1. Who discovered radioactivity?2. Definechemistry.3. Who is the founder of modern algebra?4. What are the symptoms of constipation?5. What is respiration?6. What causes air to move in and out of the lungs?7. Name the parts of blood.8. What is the function of haemoglobin in red blood
cells?9. Which is the most important part of a seed?10. What is osmosis?Q.3.Answerthequestionsindetail.(anyfive)(5×6)1. Explain the process of digestion of food in the mouth
and the stomach.2. Writebrieflyaboutthemeasurementoftime,length,
mans, temperature and volume.3. Describe the structure of human heart.
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4. List and describe the four components of blood and their functions.
5. Describe the structure of a seed.6. Describedifferentstagesofthescientificmethod7. Describe the digestion of carbohydrates and proteins.
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Model Paper No-12ndTerm(Units5-8)
TimeAllowed:2:00Hours TotalMarks:100Part-A(MultipleChoiceQuestions)• Fifteen(15)MultipleChoiceQuestions(MCQs) aregiveninthispart.Allquestionscarryequal marks. (15×2)1. The non-living part of any ecosystem is called
the: (a) habitat (b) community (c) population (d) environment2. Organismsthatmaketheirownfoodarecalled: (a) autotrophs (b) heterotrophs (c) consumers (d) decomposers3. Agreatvarietyofplantsandanimalsisfoundin
a: (a) desert habitat (b) pond habitat (c) tropical rainforest habitat (d) grassland habitat4. Thewaterthatsoaksintothegroundiscalled: (a) earth water (b) ground water (c) water table (d) aquifer5. Runningwatercollectsinlarge,deep
depressionsintheearth’scrustandforms: (a) river (b) a stream (c) a lake (d) a sea6. Placeswheregroundwaterbubblesorflowsout
ofcracksintherocksautomaticallyarecalled: (a) geysers (b) springs (c) icebergs (d) lakes
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7. Anatomhasnooverallchargeifitcontainsequalnumberof:
(a) electrons and neutrons (b) electrons and protons (c) protons and neutrons (d) positrons and neutrons8. Whichofthefollowingdescribeswhathappens
whenanatombecomesapositiveionwithacharge?
(a) the atom gains 2 protons (b) the atom loses 2 protons (c) the atom loses 2 electrons (d) the atom gains 2 electrons9. Thecorrectchemicalformulaforcalcium
chlorideis: (a) CaCl (b) Ca2Cl (c) CaCl2 (d) Ca2Cl210. Lightingamatchisanexampleofa: (a) physical change (b) chemical change (c) change in pressure (d) change of colour11. Anexampleofachemicalchangeis: (a) boiling of water (b) evaporation of water (c) burning of paper (d) melting of ice12. Theredcolourofaroseturnsbrown.Itisa: (a) physical change (b) chemical change (c) reversible change (d) sudden change13. Themajorsourcesofwaterpollutionare: (a) human wastes (b) industrial wastes (c) agricultural chemicals (d) all of them
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14. Whosestatementisthis? “Whenelectronsjumpfromoneshelltotheother,
energyisabsorbedorevolved” (a) James Chadwick (b) Rutherford (c) Niels Bohr (d) John Dalton15. Whichoneisanon-reversiblechange? (a) rotting egg (b) mixing of salt in water (c) switching on a tube light (d) wetting a dry clothPart-B(OpenEndedQuestions) Marks:70Q.1.Fillintheblanks. (5×2)1. Plants use solar energy to make food so, they are
__________.2. Water moves easily through porous socks which are
called _______________.3. Helium (He), neon (Ne), argon (Ar), krypton (Kr),
etc are __________.4. Burning of paper is a ____________.5. Metal status _________ very slowly.Q.2 Answerthequestioninshort. (10×3)1. What is a habitat?2. What is a parasite?3. Why is the earth called water planet?4. What do you mean by soft and hand water?5. What were the ideas of John Dalton about an atom?6. Definevalency.7. What is hydrogenation?8. Defineplastics.9. In what part of an atom is most of its mass located?
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10. Defineachemicalchange.Q.3.Answerthequestionsindetail.(anyfive)(5×6)1. Describe factors that can bring daily and yearly
changes in the habitat2. Explain, how water is the most essential element of
life?3. Describe the structure of an atom.4. Explain with examples that a chemical change brings
change in the proper ties of a substance.5. Explain reversible and non-reversible changes with
examples.6. What makes our water impure?7. State the law of constant composition and give
examples.
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Model Paper No-22ndTerm(Units5-8)
TimeAllowed:2:00Hours TotalMarks:100Part-A(MultipleChoiceQuestions)• Fifteen(15)MultipleChoiceQuestions(MCQs) aregiveninthispart.Allquestionscarryequal marks. (15×2)1. Agreatvarietyofplantsandanimalsisfoundin
a: (a) desert habitat (b) pond habitat (c) tropical rainforest habitat (d) grassland habitat2. Seals, penguins and turtles use __________ to
moveinwater. (a)fins (b)webbedfeet (c)tubefeet (d)flippers3. Bychangingcolourananimalcanblendintoits
surrounding and deceive its predator or prey.Thispropertyiscalled:
(a)camouflage (b)mimicry (c) predation (d) competition4. Placeswheregroundwaterbubblesorflowsout
ofcracksintherocksautomaticallyarecalled: (a) geysers (b) springs (c) icebergs (d) lakes5. Themajorsourcesofwaterpollutionare: (a) human wastes (b) industrial wastes (c) agricultural chemicals (d) all of them
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6. Weusewaterduringshowering: (a) 10% (b) 20 % (c) 45% (d) 14%7. The correct chemical formula for calcium
chlorideis: (a) CaCl (b) Ca2Cl (c) CaCl2 (d) Ca2Cl28. Whosestatementisthis? “Whenelectronsjumpfromoneshelltotheother,
energyisabsorbedorevolved” (a) James Chadwick (b) Rutherford (c) Niels Bohr (d) John Dalton9. ThenumberofelectronsinN-shellcanbe: (a) 2 (b) 8 (c) 18 (d) 3210. Theredcolourofaroseturnsbrown.Itisa: (a) physical change (b) chemical change (c) reversible change (d) sudden change11. Whichoneisanon-reversiblechange? (a) rotting egg (b) mixing of salt in water (c) switching on a tube light (d) wetting a dry cloth12. Thecolourofoxygengasis: (a) pink (b) white (c) yellow (d) none of them, butt colourless13. Organismsthatmaketheirownfoodarecalled: (a) autotrophs (b) heterotrophs (c) consumers (d) decomposers
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14. Runningwatercollectsinlarge,deepdepressionsintheearth’scrustandforms:
(a) river (b) a stream (c) a lake (d) a sea15. Whichof the followingdescribeswhathappens
when an atom becomes a positive ion with acharge?
(a) the atom gains 2 protons (b) the atom loses 2 protons (c) the atom loses 2 electrons (d) the atom gains 2 electronsPart-B(OpenEndedQuestions) Marks:70Q.1.Fillintheblanks. (5×2)1. __________________ is essential for life.2. Rivers, lakes and ponds are the sources of _______.3. The number of protons in an atom is called ______.4. _______________ react with oxygen of air and
change chemically.5. Plants use solar energy to make food so, they are
__________.Q.2 Answerthefollowingquestioninshort. (10×3)1. What is a parasite?2. Defineadaptation.3. What is a glacier?4. Definedistillationofwater.5. Defineamoleculeandanion.6. Write three uses of isotopes in medicines.7. Give three examples of non-reversible changes8. What is meant by a physical change?9. What do you mean by soft and hand water?
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10. Definevalency.Q.3 Answerthequestionsindetail.(anyfive) (5×6)1. Explain a food chain and a food web with examples.2. How can we conserve water?3. What is an ion? How ions are formed?4. Discuss advantages and harmful effects of chemical
fertilizers.5. Describe factors that can bring daily and yearly
changes in the habitat6. Explain, how water is the most essential element of
life?7. Describe the structure of an atom.
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Model Paper No-32ndTerm(Units5-8)
TimeAllowed:2:00Hours TotalMarks:100Part-A(MultipleChoiceQuestions)• Fifteen(15)MultipleChoiceQuestions(MCQs) aregiveninthispart.Allquestionscarryequal marks. (15×2)1. Plantsuse____________forphotosynthesis. (a) oxygen (b) nitrogen (c) carbon dioxide (d) hydrogen2. Bychangingcolourananimalcanblendintoits
surroundinganddeceiveitspredatororprey.Thispropertyiscalled:
(a)camouflage (b)mimicry (c) predation (d) competition3. Thenon-livingpartofanyecosystemiscalled
the: (a) habitat (b) community (c) population (d) environment4. Heavymechanicalcomplexes,oilrefineries
andnuclearreactorsuse________forcoolingpurpous.
(a) steam (b) water (c) nitrogen gas (d) oxygen gas5. Weusewaterduringshowering: (a) 10% (b) 20 % (c) 45% (d) 14%6. Thewaterthatsoaksintothegroundiscalled: (a) earth water (b) ground water (c) water table (d) aquifer
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7. Thecorrectchemicalformulaforsugaris: (a) C11 H22 O12 (b) C11 H12 O22 (c) C22 H11 O12 (d) C12 H22 O118. ThenumberofelectronsinN-shellcanbe: (a) 2 (b) 8 (c) 18 (d) 329. Anatomhasnooverallchargeifitcontainsequal
numberof: (a) electrons and neutrons (b) electrons and protons (c) protons and neutrons (d) positrons and neutrons10. Theprocess that changesvegetableoil into fats
(Banaspatighee)iscalled: (a) condensation (b) reversible change (c) hydrogenation (d) Non-reversible change11. Thecolourofoxygengasis: (a) pink (b) white (c) yellow (d) none of them, butt colourless12. Lightingamatchisanexampleofa: (a) physical change (b) chemical change (c) change in pressure (d) change of colour13. Theredcolourofaroseturnsbrown.Itisa: (a) physical change (b) chemical change (c) reversible change (d) sudden change14. The correct chemical formula for calcium
chlorideis: (a) CaCl (b) Ca2Cl (c) CaCl2 (d) Ca2Cl2
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15. Placeswheregroundwaterbubblesorflowsoutofcracksintherocksautomaticallyarecalled:
(a) geysers (b) springs (c) icebergs (d) lakesPart-B(OpenEndedQuestions) Marks:70Q.1.Fillintheblanks. (5×2)1. A coniferous forest is found in ________
environment.2. Harmful and unwanted substances in water are
called ________.3. A ________ is the particle with no change.4. Metal status ________ very slowly.5. Burning of paper is a ________.Q.2 Answerthefollowingquestioninshort. (10×3)1. What are autotrophs and heterotrophs?2. What is a habitat?3. Definewaterpollution.4. Why is the earth called water planet?5. In what part of an atom is most of its mass located?6. What were the ideas of John Dalton about an atom?7. Defineachemicalchange.8. What is hydrogenation?9. What is a parasite?10. Defineplastics.Q.3.Answerthequestionsindetail.(anyfive)(5x6)1. What are the effects of humidity on life?2. What makes our water impure?3. State the law of constant composition and give
examples.4. Explain reversible and non-reversible changes with
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examples.5. Explain with examples that a chemical change brings
change in the proper ties of a substance.6. Explain, how water is the most essential element of
life?7. Discuss advantages and harmful effects of chemical
fertilizers.
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Model Paper No-42ndTerm(Units5-8)
TimeAllowed:2:00Hours TotalMarks:100Part-A(MultipleChoiceQuestions)• Fifteen(15)MultipleChoiceQuestions(MCQs) aregiveninthispart.Allquestionscarryequal marks. (15×2)1. Seals,penguinsandturtlesuse________tomove
in water. (a)fins (b)webbedfeet (c)tubefeet (d)flippers2. The non-living part of any ecosystem is called
the: (a) habitat (b) community (c) population (d) environment3. Plantsuse____________forphotosynthesis. (a) oxygen (b) nitrogen (c) carbon dioxide (d) hydrogen4. Themajorsourcesofwaterpollutionare: (a) human wastes (b) industrial wastes (c) agricultural chemicals (d) all of them5. Thewaterthatsoaksintothegroundiscalled: (a) earth water (b) ground water (c) water table (d) aquifer6. Heavymechanicalcomplexes,oilrefineries
andnuclearreactorsuse________forcoolingpurpous.
(a) steam (b) water (c) nitrogen gas (d) oxygen gas
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7. Whosestatementisthis? “Whenelectronsjumpfromoneshelltotheother,
energyisabsorbedorevolved” (a) James Chadwick (b) Rutherford (c) Niels Bohr (d) John Dalton8. Anatomhasnooverallchargeifitcontainsequal
numberof: (a) electrons and neutrons (b) electrons and protons (c) protons and neutrons (d) positrons and neutrons9. Thecorrectchemicalformulaforsugaris: (a) C11 H22 O12 (b) C11 H12 O22 (c) C22 H11 O12 (d) C12 H22 O1110. Whichoneisanon-reversiblechange? (a) rotting egg (b) mixing of salt in water (c) switching on a tube light (d) wetting a dry cloth11. Lightingamatchisanexampleofa: (a) physical change (b) chemical change (c) change in pressure (d) change of colour12. Theprocess that changesvegetableoil into fats
(Banaspatighee)iscalled: (a) condensation (b) reversible change (c) hydrogenation (d) Non-reversible change13. Anexampleofachemicalchangeis: (a) boiling of water (b) evaporation of water (c) burning of paper (d) melting of ice
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14. Whichof the followingdescribeswhathappenswhen an atom becomes a positive ion with acharge?
(a) the atom gains 2 protons (b) the atom loses 2 protons (c) the atom loses 2 electrons (d) the atom gains 2 electrons15. Runningwatercollectsinlarge,deepdepressions
intheearth’scrustandforms: (a) river (b) a stream (c) a lake (d) a seaPart-B(OpenEndedQuestions) Marks:70Q.1.Fillintheblanks. (5×2)1. Water moves easily through porous socks which are
called __________.2. __________ is essential for life.3. Helium (He), neon (Ne), argon (Ar), krypton (Kr),
etc are __________.4. The number of protons in an atom is called
__________.5. __________ react with oxygen of air and change
chemically.Q.2 Answerthefollowingquestioninshort. (10×3)1. Defineadaptation.2. What role does sunlight play in an ecosystem?3. What are autotrophs and heterotrophs?4. What do you mean by soft and hand water?5. What is a glacier?6. Definedistillationofwater7. Definevalency.
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8. Defineamoleculeandanion.9. Give three examples of non-reversible changes10. What is meant by a physical change?Q.3.Answerthequestionsindetail.(anyfive)(5×6)1. Explain, how water is the most essential element of
life?2. Explain a food chain and a food web with examples.3. Describe the structure of an atom.4. What is an ion? How ions are formed?5. Discuss advantages and harmful effects of chemical
fertilizers.6. Describe factors that can bring daily and yearly
changes in the habitat7. How can we conserve water?
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Model Paper No-13rdTerm(Units9-13)
TimeAllowed:2:00Hours TotalMarks:100Part-A(MultipleChoiceQuestions)• Fifteen(15)MultipleChoiceQuestions(MCQs) aregiveninthispart.Allquestionscarryequal marks. (15×2)1. Heatenergytravelsthroughametalspooninhot
teamostlyby: (a) radiation (b) conduction (c) convection (d) insulation2. What is the name given to any material that
transfersheatenergyeasily? (a) thermal (b) metal (c) insulator (d) conductor3. Landandseabreezesblowdueto: (a) conduction of heat (b) convection of heat (c) radiation of heat (d) emission of heat4. The splitting of white light into its component
coloursiscalled: (a) dispersion of light (b)reflectionoflight (c) interference of light (d)irregularreflection5. Weseeamirageduetothe: (a)reflectionoflight (b)totalinternalreflection (c) dispersion of light (d) spectrum of light
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6. Whenallthecoloursoflightarereflectedintooureyes,theobjectappears:
(a) black (b) red (c) green (d) white7. Hittinganobjectharderwillmakethevolume: (a) softer (b) the same (c) lower (d) louder8. Thelowestpartsofatransversewavesarecalled: (a) crests (b) compressions (c) rarefactions (d) troughs9. Soundwavestravelmostquicklythrough: (a) solids (b) gases (c) air (d) liquids10. Theenergysourcecanbe: (a) a battery (b) a light bulb (c) a metal wire (d) an electric motor11. Theelectricalenergyusedinourhouseis
measuredinunitsof: (a) kilowatt-hours (b) amperes (c) kilowatts (d) watt-hours12 Stardistancesareusuallymeasuredin: (a) meters (b) kilometres (c) light-years (d) yards13. Bymixingamagentaandcyanpigmentswecan
producethecolour: (a) blue (b) green (c) white (d) red14. Whenthereareseveralpathsforacurrentto
take,thecircuitiscalled: (a) series circuit (b) parallel circuit
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(c) incomplete circuit (d) full circuit15. Polaris(NorthStar)isintheconstellation: (a) Ursa Minor (b) Orion (c) Draco (d) TaurusPart-B(OpenEndedQuestions) Marks:70Q.1.Fillintheblanks. (5×2)1. Radiation is the fastest way to transfer ________.2. A ________ is a transparent wedge-shaped block of
glass.3. A material thing through which a wave travels is
called a ________.4. A large group of stars, gas and dust is a ________.5. The scientific studyof theuniverse, its origin and
development is called ________.Q.2 Answerthefollowingquestioninshort. (10×3)1. What is conduction of heat?2. How does convection of heat occur?3. What is refractive index?4. Whatismeantbytotalinternalreflection?5. Defineultrasoundandinfrasound.6. What is the unit of the loudness of a sound?7. Definekilowatthour.8. What is supernova?9. State Ohm’s law10. What is a constellation?Q.3.Answerthequestionsindetail.(anyfive)(5×6)1. What is convection? How does it occur?2. What is the law of refraction? Verify it through an
activity.3. Describe loudness and pitch of the sound.
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4. Write a note on electric power.5. Describe the three main types of galaxies. 6. Write a brief note on “hearing loss”.7. Write a note on resistance.
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Model Paper No-23rdTerm(Units9-13)
TimeAllowed:2:00Hours TotalMarks:100Part-A(MultipleChoiceQuestions)• Fifteen(15)MultipleChoiceQuestions(MCQs) aregiveninthispart.Allquestionscarryequal marks. (15×2)1. Landandseabreezesblowdueto: (a) conduction of heat (b) convection of heat (c) radiation of heat (d) emission of heat2. How is the transfer of heat slowed down in a
thermosbottle? (a) by the use of a vacuum (b) by the use of paper (c) by the use of a metal sheet (d) by the use of wood3. Whattypeofenergytransferproducesweather? (a) radiation (b) convection (c) conduction (d) atmospheric4. Whenallthecoloursoflightarereflectedinto
oureyes,theobjectappears: (a) black (b) red (c) green (d) white5. Bymixingamagentaandcyanpigmentswecan
producethecolour: (a) blue (b) green (c) white (d) red6. Thedistancebetweenonecrestandthenextcrest
isthewave’s: (a) amplitude (b) wavelength
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(c) frequency (d) speed7. Soundwavestravelmostquicklythrough: (a) solids (b) gases (c) air (d) liquids8. Whenthereareseveralpathsforacurrentto
take,thecircuitiscalled: (a) series circuit (b) parallel circuit (c) incomplete circuit (d) full circuit9. “Theresistanceisequaltothevoltagedividedby
thecurrent”.Thislawwaspresentedby: (a) George Ohm (b) George Samuel (c) Alessandro Volta (d) James Watt10. Stardistancesareusuallymeasuredin: (a) meters (b) kilometres (c) light-years (d) yards11. Polaris(NorthStar)isintheconstellation: (a) Ursa Minor (b) Orion (c) Draco (d) Taurus12. Betelgeuseisa: (a) red star (b) yellow star (c) blue star (d) orange star13. Whatisthenamegiventoanymaterialthat
transfersheatenergyeasily? (a) thermal (b) metal (c) insulator (d) conductor14. Weseeamirageduetothe: (a)reflectionoflight (b)totalinternalreflection (c) dispersion of light (d) spectrum of light15. Thelowestpartsofatransversewavesarecalled: (a) crests (b) compressions (c) rarefactions (d) troughs
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Part-B(OpenEndedQuestions) Marks:70Q.1.Fillintheblanks. (5×2)1. Anymaterialthatflowsiscalleda__________.2. The distance a wave covers or travels in one second
is called its __________.3. Watt is the unit for __________.4. The last stage of a low-mass star’s life is called
__________.5. Radiation is the fastest way to transfer __________.Q.2 Answerthefollowingquestioninshort. (10×3)1. How does convection of heat occur?2. How can the food be kept hot for a longer period?3. What are the primary pigment colours?4. Defineawave.5. What is electric current?6. Defineacircuit.7. What is a light-year?8. Defineagalaxy.9. Whatismeantbytotalinternalreflection?10. What is the unit of the loudness of a sound?Q.3.Answerthequestionsindetail.(Anyfive)(5×6)1. Write everyday applications of conduction of heat.2. Describe the basic properties of waves.3. Howdoelectronsflow?Explain.4. Explain the Big Bang theory of the origins of the
universe.5. What is convection ? How does it occur?6. What is the law of refraction? Verify it through an
activity.7. Describe loudness and pitch of the sound.
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Model Paper No-33rdTerm(Units9-13)
TimeAllowed:2:00Hours TotalMarks:100Part-A(MultipleChoiceQuestions)• Fifteen(15)MultipleChoiceQuestions(MCQs) aregiveninthispart.Allquestionscarryequal marks. (15×2)1. Refractiveindexofglassis: (a) 1.47 (b) 2.42 (c) 1.5 (d) 1.332. Whattypeofenergytransferproducesweather? (a) radiation (b) convection (c) conduction (d) atmospheric3. Heatenergytravelsthroughametalspooninhot
teamostlyby: (a) radiation (b) conduction (c) convection (d) insulation4. Asoundwaveisa: (a) transverse wave (b) longitudinal wave (c) reverse wave (d) standing wave5. Thedistancebetweenonecrestandthenextcrest
isthewave’s: (a) amplitude (b) wavelength (c) frequency (d) speed6. Thesplittingofwhitelightintoitscomponent
coloursiscalled: (a)dispersionoflight (b)reflectionoflight (c)interferenceoflight (d)irregularreflection7. Aresistancechangestheelectricalenergyinto: (a) chemical energy (b) heat
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(c) sound (d) nuclear energy8. “Theresistanceisequaltothevoltagedividedby
thecurrent”.Thislawwaspresentedby: (a) George Ohm (b) George Samuel (c) Alessandro Volta (d) James Watt9. Hittinganobjectharderwillmakethevolume: (a) softer (b) the same (c) lower (d) louder10. Ourneighbouringgalaxyisnamedas: (a) Cepheus (b) Andromeda (c) Canis Major (d) Taurus11. Betelgeuseisa: (a) red star (b) yellow star (c) blue star (d) orange star12. Theenergysourcecanbe: (a) a battery (b) a light bulb (c) a metal wire (d) an electric motor13 Stardistancesareusuallymeasuredin: (a) meters (b) kilometres (c) light-years (d) yards14. Soundwavestravelmostquicklythrough: (a) solids (b) gases (c) air (d) liquids15. Whenallthecoloursoflightarereflectedinto
oureyes,theobjectappears: (a) black (b) red (c) green (d) whitePart-B(OpenEndedQuestions) Marks:70Q.1.Fillintheblanks. (5×2)1. The angle of incidence at which maximum refraction
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occurs is called the __________.2. A __________ is a repeated to-and-fro or up-and-
down motion.3. Theflowofelectronsthroughaconductoriscalled
__________.4. The scientific studyof theuniverse, its origin and
development is called __________.5. A large group of stars, gas and dust is a _________.Q.2 Answerthefollowingquestioninshort. (10×3)1. What is refraction of light?2. What is conduction of heat?3. List the four basic properties of waves.4. What is refractive index?5. State Ohm’s law.6. Defineultrasoundandinfrasound.7. What is a constellation?8. Definekilowatthour.9. How does convection of heat occur?10. What is supernova?Q.3.Answerthequestionsindetail.(anyfive)(5×6)1. Whatisthetotalintervalreflection?Explainitwith
an example.2. Write a brief note on “hearing loss”.3. Write a note on resistance.4. Describe the three main types of galaxies. 5. Write a note on electric power.6. What is the law of refraction? Verify it through an
activity.7. Explain the Big Bang theory of the origins of the
universe.
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Model Paper No-43rdTerm(Units9-13)
TimeAllowed:2:00Hours TotalMarks:100Part-A(MultipleChoiceQuestions)• Fifteen(15)MultipleChoiceQuestions(MCQs) aregiveninthispart.Allquestionscarryequal marks. (15×2)1. Howisthetransferofheatsloweddownina
thermosbottle? (a) by the use of a vacuum (b) by the use of paper (c) by the use of a metal sheet (d) by the use of wood2. Heatenergytravelsthroughametalspooninhot
teamostlyby: (a) radiation (b) conduction (c) convection (d) insulation3. Refractiveindexofglassis: (a) 1.47 (b) 2.42 (c) 1.5 (d) 1.334. Bymixingamagentaandcyanpigmentswecan
producethecolour: (a) blue (b) green (c) white (d) red5. Thesplittingofwhitelightintoitscomponent
coloursiscalled: (a) dispersion of light (b)reflectionoflight (c) interference of light (d)irregularreflection
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6. Asoundwaveisa: (a) transverse wave (b) longitudinal wave (c) reverse wave (d) standing wave7. When there are several paths for a current to
take,thecircuitiscalled: (a) series circuit (b) parallel circuit (c) incomplete circuit (d) full circuit8. Hittinganobjectharderwillmakethevolume: (a) softer (b) the same (c) lower (d) louder9. Aresistancechangestheelectricalenergyinto: (a) chemical energy (b) heat (c) sound (d) nuclear energy10. Polaris(NorthStar)isintheconstellation: (a) Ursa Minor (b) Orion (c) Draco (d) Taurus11. Theenergysourcecanbe: (a) a battery (b) a light bulb (c) a metal wire (d) an electric motor12. Ourneighbouringgalaxyisnamedas: (a) Cepheus (b) Andromeda (c) Canis Major (d) Taurus13. Theelectricalenergyusedinourhouseis
measuredinunitsof: (a) kilowatt-hours (b) amperes (c) kilowatts (d) watt-hours14. Thelowestpartsofatransversewavesarecalled: (a) crests (b) compressions (c) rarefactions (d) troughs
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15. Weseeamirageduetothe: (a)reflectionoflight (b)totalinternalreflection (c) dispersion of light (d) spectrum of lightPart-B(OpenEndedQuestions) Marks:70Q.1.Fillintheblanks. (5×2)1. A ________ is a transparent wedge-shaped block of
glass.2. Anymaterialthatflowsiscalleda________.3. A material thing through which a wave travels is
called a ________.4. Watt is the unit for ________.5. The last stage of a low-mass star’s life is called
________.Q.2 Answerthefollowingquestioninshort. (10×3)1. How can the food be kept hot for a longer period?2. How does heat of the sun reach the Earth?3. What is refraction of light?4. Whatismeantbytotalinternalreflection?5. What are the primary pigment colours?6. Defineawave.7. What is the unit of the loudness of a sound?8. What is electric current?9. What is a light-year?10. Defineagalaxy.Q.3.Answerthequestionsindetail.(anyfive)(5×6)1. What is the law of refraction? Verify it through an
activity.2. Write everyday applications of conduction of heat.
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3. Describe loudness and pitch of the sound.4. Howdoelectronsflow?Explain.5. Explain the Big Bang theory of the origins of the
universe.6. What is convection? How does it occur?7. Describe the basic properties of waves.
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Model Paper No-1FinalTerm(Units1-13)
TimeAllowed:2:00Hours TotalMarks:100Part-A(MultipleChoiceQuestions)• Fifteen(15)MultipleChoiceQuestions(MCQs) aregiveninthispart.Allquestionscarryequal marks. (15×2)1. Ahypothesisistestedbya(n): (a) conclusion (b) data (c) experiment (d) inference2. Degree Celsius (°C) or Degree Fahrenheit (°F)
areunitsof: (a) time (b) volume (c) length (d) temperature3. Thestudyofforce,energyandmotionofobjects
iscalled: (a) chemistry (b) physics (c) biology (d) mathematics4. Whathelpsprotectseeds? (a) fruit (b) wind (c) bees (d) cotyledon5. Theembryonicleavesofanembryoare: (a) root hairs (b) radicles (c) plumules (d) cotyledons6. Thenon-livingpartofanyecosystemiscalled
the: (a) habitat (b) community (c) population (d) environment
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7. Heavymechanicalcomplexes,oilrefineriesandnuclearreactorsuse________forcoolingpurpous.
(a) steam (b) water (c) nitrogen gas (d) oxygen gas8. Whosestatementisthis? “Whenelectronsjumpfromoneshelltotheother,
energyisabsorbedorevolved” (a) James Chadwick (b) Rutherford (c) Niels Bohr (d) John Dalton9. Lightingamatchisanexampleofa: (a) physical change (b) chemical change (c) change in pressure (d) change of colour10. Refractiveindexofglassis: (a) 1.47 (b) 2.42 (c) 1.5 (d) 1.3311. When all the colours of light are reflected into
oureyes,theobjectappears: (a) black (b) red (c) green (d) white12. Asoundwaveisa: (a) transverse wave (b) longitudinal wave (c) reverse wave (d) standing wave13. Agreatvarietyofplantsandanimalsisfoundin
a: (a) desert habitat (b) pond habitat (c) tropical rainforest habitat
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(d) grassland habitat14. Thecolourofoxygengasis: (a) pink (b) white (c) yellow (d) none of them, butt colourless15. When there are several paths for a current to
take,thecircuitiscalled: (a) series circuit (b) parallel circuit (c) incomplete circuit (d) full circuitPart-B(OpenEndedQuestions) Marks:70Q.1.Fillintheblanks. (5×2)1. Kilogram is the unit of__________.2. The __________ protects a seed.3. Helium (He), neon (Ne), argon (Ar), krypton (Kr),
etc are __________.4. A __________ is a transparent wedge-shaped block
of glass.5. A large group of stars, gas and dust is a __________.Q.2 Answerthefollowingquestioninshort. (10×3)1. What is science?2. Who discovered radioactivity?3. What is asthma?5. Which is the most important part of a seed?6. Definedistillationofwater7. What were the ideas of John Dalton about an atom?8. How can the food be kept hot for a longer period?9. What is refractive index?10. What is conduction of heat?11. What is a light-year?
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Q.3.Answerthequestionsindetail.(anyfive)(5×6)1. Describedifferentstagesofthescientificmethod.2. Write brief note on transplantation.3. Describe the structure of an atom.4. What is the law of refraction? Verify it through an
activity5. Write a note on electric power.6. Explain, how water is the most essential element of
life?7. What is convection? How does it occur?
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Model Paper No-2FinalTerm(Units1-13)
TimeAllowed:2:00Hours TotalMarks:100Part-A(MultipleChoiceQuestions)• Fifteen(15)MultipleChoiceQuestions(MCQs) aregiveninthispart.Allquestionscarryequal marks. (15×2)1. Thestudyofforce,energyandmotionofobjects
iscalled: (a) chemistry (b) physics (c) biology (d) mathematics2. Exchangeofgasesoccursbetweenthe________
andcapillaries. (a) alveoli (b) bronchioles (c) bronchi (d) trachea 3. Itisdonebyoxygengaswhichhelpsinreleasing
energyfromfood. (a) breathing (b) digestion (c) respiration (d) reproduction4. The non-living part of any ecosystem is called
the: (a) habitat (b) community (c) population (d) environment5. Agreatvarietyofplantsandanimalsisfoundin
a: (a) desert habitat (b) pond habitat (c) tropical rainforest habitat (d) grassland habitat
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6. Plantsuse____________forphotosynthesis. (a) oxygen (b) nitrogen (c) carbon dioxide (d) hydrogen7. Lightingamatchisanexampleofa: (a) physical change (b) chemical change (c) change in pressure (d) change of colour8. Thecolourofoxygengasis: (a) pink (b) white (c) yellow (d) none of them, butt colourless9. Heatenergytravelsthroughametalspooninhot
teamostlyby: (a) radiation (b) conduction (c) convection (d) insulation10. Asoundwaveisa: (a) transverse wave (b) longitudinal wave (c) reverse wave (d) standing wave11. When there are several paths for a current to
take,thecircuitiscalled: (a) series circuit (b) parallel circuit (c) incomplete circuit (d) full circuit12. Theenergysourcecanbe: (a) a battery (b) a light bulb (c) a metal wire (d) an electric motor13. Degree Celsius (°C) or Degree Fahrenheit (°F)
areunitsof: (a) time (b) volume (c) length (d) temperature14. Theembryonicleavesofanembryoare:
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(a) root hairs (b) radicles (c) plumules (d) cotyledons15. Whosestatementisthis? “Whenelectronsjumpfromoneshelltotheother,
energyisabsorbedorevolved” (a) James Chadwick (b) Rutherford (c) Niels Bohr (d) John DaltonPart-B(OpenEndedQuestions) Marks:70Q.1.Fillintheblanks. (5×2)1. The _________ is a large tube that suns from the
mouth to the stomach.2. Plants use solar energy to make food so, they are
_________.3. Burning of paper is a _________.4. A material thing through which a wave travels is
called a _________.5. Kilogram is the unit of _________.Q.2 Answerthefollowingquestioninshort. (10×3)1. Who discovered radioactivity?2. What causes air to move in and out of the lungs?3. What is a habitat?4. Defineadaptation5. Write three uses of isotopes in medicines.6. Give three examples of non-reversible changes7. Defineawave.8. What is electric current?9. Which is the most important part of a seed?10. What were the ideas of John Dalton about an atom?Q.3.Answerthefollowingindetail.(Anyfive)(5×6)1. Explain the process of digestion of food in the mouth
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and the stomach.2. Describe factors that can bring daily and yearly
changes in the habitat.3. Explain with examples that a chemical change brings
change in the proper ties of a substance.4. Describe loudness and pitch of the sound.5. Describedifferentstagesofthescientificmethod.6. Write brief note on transplantation.7. Describe the structure of an atom.
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Model Paper No-3FinalTerm(Units1-13)
TimeAllowed:2:00Hours TotalMarks:100Part-A(MultipleChoiceQuestions)• Fifteen(15)MultipleChoiceQuestions(MCQs) aregiveninthispart.Allquestionscarryequal marks. (15×2)1. Whichtissueofaplanttransportswaterand
mineralsfromrootstoleaves? (a) xylem (b) phloem (c) bark (d) mesophyll2. Itisdonebyoxygengaswhichhelpsinreleasing
energyfromfood. (a) breathing (b) digestion (c) respiration (d) reproduction3. Ahypothesisistestedbya(n): (a) conclusion (b) data (c) experiment (d) inference4. Placeswheregroundwaterbubblesorflowsout
ofcracksintherocksautomaticallyarecalled: (a) geysers (b) springs (c) icebergs (d) lakes5. Plantsuse____________forphotosynthesis. (a) oxygen (b) nitrogen (c) carbon dioxide (d) hydrogen6. Whathelpsprotectseeds? (a) fruit (b) wind (c) bees (d) cotyledon
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7. Landandseabreezesblowdueto: (a) conduction of heat (b) convection of heat (c) radiation of heat (d) emission of heat8. Heatenergytravelsthroughametalspooninhot
teamostlyby: (a) radiation (b) conduction (c) convection (d) insulation9. Heavymechanicalcomplexes,oilrefineries
andnuclearreactorsuse________forcoolingpurpous.
(a) steam (b) water (c) nitrogen gas (d) oxygen gas10. Betelgeuseisa: (a) red star (b) yellow star (c) blue star (d) orange star11. Theenergysourcecanbe: (a) a battery (b) a light bulb (c) a metal wire (d) an electric motor12. Refractiveindexofglassis: (a) 1.47 (b) 2.42 (c) 1.5 (d) 1.3313. Asoundwaveisa: (a) transverse wave (b) longitudinal wave (c) reverse wave (d) standing wave14. Lightingamatchisanexampleofa: (a) physical change (b) chemical change (c) change in pressure (d) change of colour
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15. Thenon-livingpartofanyecosystemiscalledthe:
(a) habitat (b) community (c) population (d) environmentPart-B(OpenEndedQuestions) Marks:70Q.1.Fillintheblanks. (5×2)1. ___________ is the movement of materials from a
region of higher concentration to the region of lower concentration.
2. Water moves easily through porous socks which are called ___________.
3. Radiation is the fastest way to transfer ___________.4. A large group of stars, gas and dust is a ___________.5. A ___________ is a transparent wedge-shaped block
of glass.Q.2 Answerthefollowingquestioninshort. (10×3)1. What is pericardium?2. What is science?3. Why is the earth called water planet?4. What is asthma?5. What is conduction of heat?6. Definedistillationofwater7. What is a light-year?8. How can the food be kept hot for a longer period?9. Who discovered radioactivity?10. What is refractive index?Q.3.Answerthequestionsindetail.(anyfive)(5×6)1. Describe the structure of human heart.2. Explain, how water is the most essential element of
life?
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3. What is convection ? How does it occur?4. Write a note on electric power.5. What is the law of refraction? Verify it through an
activity.6. Write brief note on transplantation.7. Describe loudness and pitch of the sound.
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Model Paper No-4FinalTerm(Units1-13)
TimeAllowed:2:00Hours TotalMarks:100Part-A(MultipleChoiceQuestions)• Fifteen(15)MultipleChoiceQuestions(MCQs) aregiveninthispart.Allquestionscarryequal marks. (15×2)1. Exchangeofgasesoccursbetweenthe________
andcapillaries. (a) alveoli (b) bronchioles (c) bronchi (d) trachea2. Ahypothesisistestedbya(n): (a) conclusion (b) data (c) experiment (d) inference3. Which tissue of a plant transports water and
mineralsfromrootstoleaves? (a) xylem (b) phloem (c) bark (d) mesophyll4. Agreatvarietyofplantsandanimalsisfoundin
a: (a) desert habitat (b) pond habitat (c) tropical rainforest habitat (d) grassland habitat5. Whathelpsprotectseeds? (a) fruit (b) wind (c) bees (d) cotyledon6. Placeswheregroundwaterbubblesorflowsout
ofcracksintherocksautomaticallyarecalled: (a) geysers (b) springs (c) icebergs (d) lakes
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7. Thecolourofoxygengasis: (a) pink (b) white (c) yellow (d) none of them, butt colourless8. Heavymechanicalcomplexes,oilrefineries
andnuclearreactorsuse________forcoolingpurpous.
(a) steam (b) water (c) nitrogen gas (d) oxygen gas9. Landandseabreezesblowdueto: (a) conduction of heat (b) convection of heat (c) radiation of heat (d) emission of heat10. When there are several paths for a current to
take,thecircuitiscalled: (a) series circuit (b) parallel circuit (c) incomplete circuit (d) full circuit11. Refractiveindexofglassis: (a) 1.47 (b) 2.42 (c) 1.5 (d) 1.3312. Betelgeuseisa: (a) red star (b) yellow star (c) blue star (d) orange star13. Whenallthecoloursoflightarereflectedinto
oureyes,theobjectappears: (a) black (b) red (c) green (d) white14. Whosestatementisthis? “Whenelectronsjumpfromoneshelltotheother,
energyisabsorbedorevolved”
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(a) James Chadwick (b) Rutherford (c) Niels Bohr (d) John Dalton15. Theembryonicleavesofanembryoare: (a) root hairs (b) radicles (c) plumules (d) cotyledonsPart-B(OpenEndedQuestions) Marks:70Q.1.Fillintheblanks. (5×2)1. The ______________ protects a seed.2. The ___________ is a large tube that suns from the
mouth to the stomach.3. Helium (He), neon (Ne), argon (Ar), krypton (Kr),
etc are __________.4. Burning of paper is a ____________.5. A material thing through which a wave travels is
called a _______________.Q.2 Answerthefollowingquestioninshort. (10×3)1. What causes air to move in and out of the lungs?2. What is digestion?3. What is pericardium?4. Which is the most important part of a seed?5. What is a habitat?6. Defineadaptation7. What were the ideas of John Dalton about an atom?8. Write three uses of isotopes in medicines.9. Defineawave.10. What is electric current?Q.3.Answerthequestionsindetail.(Anyfive)(5×6)1. Write brief note on transplantation.2. Explain the process of digestion of food in the mouth
and the stomach.
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134
3. Describe the structure of an atom.4. Explain with examples that a chemical change brings
change in the proper ties of a substance.5. Describe loudness and pitch of the sound.6. Describedifferentstagesofthescientificmethod.7. Describe factors that can bring daily and yearly
changes in the habitat.
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135
SCHEME OF STUDY34 weeks 5/6 days a week Three Terms
1st Term
WEEK UNIT # NAME of UNIT PAGE #
Ist 1
WHAT IS SCIENCE? / Scientists at Work /
Scientific Method / Main Branches of Science /
Measurement in Science / Contributions of
Some Eminent Muslim & Non-Muslim
Scientists / Chapter Review / MCQs / Detailed-
Answer Questions
4 to 10
2nd 2
DIGESTION AND RESPIRATION IN HUMAN /
Digestive System /Digestive Disorders /
Respiratory System / Respiratory Disorders /
Chapter Review / MCQs / Detailed-Answer
Questions
11 to 17
3rd Revision and Test of the above topics (Units 1 & 2)
4th 3
TRANSPORT IN HUMANS AND PLANTS /
Human Blood Circulatory System /Blood /
Transplantation /Transportation in Plants /
Structure of Plant / Chapter Review / MCQs /
Detailed-Answer Questions
18 to 26
5th 4REPRODUCTION IN PLANTS / Chapter Review /
MCQs / Detailed-Answer Questions27 to 31
6th Revision and Test of the above topics (Units 3 & 4)
7th 5
LIVING TOGETHER IN AN ENVIRONMENT /
Ecosystems / The Factors Causing Changes in a
Habitat / Adaptations of Organisms / Feeding
Relationship / Activity 5:1 / Chapter Review /
MCQs / Detailed-Answer Questions
32 to 40
8th Revision and Test of the above topics (Unit 5)
9th Preparatory Tests' Week
10th 1st Term Paper (Units 1 to 5) ORAL
11th 1st Term Paper (Units 1 to 5) WRITTEN
Skylark Science 7 Key Book
136
2nd Term
WEEK UNIT # NAME of UNIT PAGE #
12th 6
WATER / Water for Life / Surface Water /
Water Beneath the Surface of Earth / Bringing
Ground Water to the Surface / Water
Impureties & its Treatment
41 to 45
13th "Cleaning of Water / Uses of Water / Chapter
Review / MCQs / Detailed Questions 46 to 49
14th Revision and Test of the above topics (Unit 6)
15th 7
STRUCTURE OF AN ATOM / Atomic and Mass
Numbers / Electronic Configuration / Valency /
Periodic Table of the Elements / Ion / Isotopes
50 to 55
16th "
Molecule / Chemical Formula / Activities 7:1
& 7:2 / Law of Constant Composition / Chapter
Review / MCQs / Detailed Questions
56 to 60
17th Revision and Test of the above topics (Unit 7)
18th 8
CHANGES AND PROCESSES AROUND US /
Types of Changes / Changes in the
Environment / Application of Chemical
Changes and Processes / Use of Fertilizers /
How Vegetable Oil Changes into Fat /
Reversible and Non-reversible Changes /
Activity 8:1 / Chapter Review / MCQs /
Detailed Questions
61 to 66
19th Revision and Test of the above topics (Unit 8)
20th Preparatory Tests' Week
21st 2nd Term Paper (Units 6 to 8) ORAL
22nd 2nd Term Paper (Units 6 to 8) WRITTEN
NOTE : Teachers may synchronize this “Scheme of Study” with our (Term Wise ) “Model Papers”, according to their specific needs.
Skylark Science 7 Key Book
137
3rd Term
WEEK UNIT # NAME of UNIT PAGE #
23rd 9
TRANSMISSION OF HEAT / Conduction /
Convection / Radiation / Everyday Applications
of Conduction of Heat / Everyday Applications
of Convection of Heat /Everyday Applications
of Radiation of Heat / The Vaccum Flask /
Activities 9:1 to 9:5 / Chapter Review / MCQs
/ Detailed Questions
67 to 75
24th 10
REFRACTION AND DISPERSION OF LIGHT /
Refraction of Light / Laws of Refraction /
Refractive Index / Dispersion of Light / Critical
Angle / Applications / Colours of Light /
Activities 10:1 to 10:4 / Chapter Review /
MCQs / Detailed Questions
76 to 87
25th Revision and Test of the above topics (Units 9 & 10)
26th 11
WAVES AND SOUND / Waves / Types of Waves
/ Properties of Waves / Properties of Sound /
Audible Frequency Range / Activity 11:1 /
Chapter Review / MCQs / Detailed Questions
88 to 96
27th 12
ELECTRICITY / What is Electricity? / Electric
Circuit & its Types / Electricity and Energy /
How do Electrons Flow? / Electrical Meters /
Dangers of Electricity / Safe Uses of Electricity
/ Activities 12:1 & 12:2 / Chapter Review /
MCQs / Detailed Questions
97 to 109
28th 13
EXPLORING THE SPACE / The Big Bang Theory
/ Stars / Life Cycle of a Star-Our Sun / Galaxies
and Star Groups / Constellations / Telescopes /
Safety Tips for Observing the Sun / Chapter
Review / MCQs / Detailed Questions
110 to 120
29th Revision and Test of the above topics (Units 11, 12 & 13)
30th Preparatory Tests' Week 1st & 2nd Term (Units 1 to 8)
31st Preparatory Tests' Week 3rd & 4th Term (Units 9 to 13)
32nd 3rd Term Paper (Units 1 to 13) (ORAL)
33rd 3rd Term Paper (Units 1 to 13) (WRITTEN)
34th "
Skylark Science 7 Key Book
138
40 weeks 5/6 days a week Four Terms1st Term
WEEK UNIT # NAME of UNIT PAGE #
Ist 1
WHAT IS SCIENCE? / Scientists at Work /
Scientific Method / Main Branches of Science /
Measurement in Science / Contributions of
Some Eminent Muslim & Non-Muslim
Scientists / Chapter Review / MCQs / Detailed-
Answer Questions
4 to 10
2nd 2
DIGESTION AND RESPIRATION IN HUMAN /
Digestive System /Digestive Disorders /
Respiratory System / Respiratory Disorders /
Chapter Review / MCQs / Detailed-Answer
Questions
11 to 17
3rd Revision and Test of the above topics (Units 1 & 2)
4th 3
TRANSPORT IN HUMANS AND PLANTS /
Human Blood Circulatory System /Blood /
Transplantation /Transportation in Plants /
Structure of Plant / Chapter Review / MCQs /
Detailed-Answer Questions
18 to 26
5th 4REPRODUCTION IN PLANTS / Chapter Review /
MCQs / Detailed-Answer Questions27 to 31
6th Revision and Test of the above topics (Units 3 & 4)
7th 5
LIVING TOGETHER IN AN ENVIRONMENT /
Ecosystems / The Factors Causing Changes in a
Habitat / Adaptations of Organisms / Feeding
Relationship / Activity 5:1 / Chapter Review /
MCQs / Detailed-Answer Questions
32 to 40
8th Revision and Test of the above topics (Unit 5)
9th Preparatory Tests' Week
10th 1st Term Paper (Units 1 to 5) ORAL & WRITTEN
Skylark Science 7 Key Book
139
2nd Term
WEEK UNIT # NAME of UNIT PAGE #
10th 6
WATER / Water for Life / Surface Water /
Water Beneath the Surface of Earth / Bringing
Ground Water to the Surface / Water
Impureties & its Treatment
41 to 45
11th "Cleaning of Water / Uses of Water / Chapter
Review / MCQs / Detailed Questions 46 to 49
12th Revision and Test of the above topics (Unit 6)
13th 7
STRUCTURE OF AN ATOM / Atomic and Mass
Numbers / Electronic Configuration / Valency /
Periodic Table of the Elements / Ion / Isotopes
50 to 55
14th "
Molecule / Chemical Formula / Activities 7:1
& 7:2 / Law of Constant Composition / Chapter
Review / MCQs / Detailed Questions
56 to 60
15th Revision and Test of the above topics (Unit 7)
16th 8
CHANGES AND PROCESSES AROUND US /
Types of Changes / Changes in the
Environment / Application of Chemical
Changes and Processes / Use of Fertilizers /
How Vegetable Oil Changes into Fat /
Reversible and Non-reversible Changes /
Activity 8:1 / Chapter Review / MCQs /
Detailed Questions
61 to 66
17th Revision and Test of the above topics (Unit 8)
18th Preparatory Tests' Week
19th 2nd Term Paper (Units 6 to 8) ORAL
20th 2nd Term Paper (Units 6 to 8) WRITTEN
Skylark Science 7 Key Book
140
3rd Term
WEEK UNIT # NAME of UNIT PAGE #
20th 9
TRANSMISSION OF HEAT / Conduction /
Convection / Radiation / Everyday Applications
of Conduction of Heat / Everyday Applications
of Convection of Heat /Everyday Applications
of Radiation of Heat / The Vaccum Flask /
Activities 9:1 to 9:5 / Chapter Review / MCQs
/ Detailed Questions
67 to 75
21st 10
REFRACTION AND DISPERSION OF LIGHT /
Refraction of Light / Laws of Refraction /
Refractive Index / Dispersion of Light / Critical
Angle / Applications / Colours of Light /
Activities 10:1 to 10:4 / Chapter Review /
MCQs / Detailed Questions
76 to 87
22nd Revision and Test of the above topics (Units 9 & 10)
23rd 11
WAVES AND SOUND / Waves / Types of Waves
/ Properties of Waves / Properties of Sound /
Audible Frequency Range / Activity 11:1 /
Chapter Review / MCQs / Detailed Questions
88 to 96
24th 12
ELECTRICITY / What is Electricity? / Electric
Circuit & its Types / Electricity and Energy /
How do Electrons Flow? / Electrical Meters /
Dangers of Electricity / Safe Uses of Electricity
/ Activities 12:1 & 12:2 / Chapter Review /
MCQs / Detailed Questions
97 to 109
25th 13
EXPLORING THE SPACE / The Big Bang Theory
/ Stars / Life Cycle of a Star-Our Sun / Galaxies
and Star Groups / Constellations / Telescopes /
Safety Tips for Observing the Sun / Chapter
Review / MCQs / Detailed Questions
110 to 120
26th Revision and Test of the above topics (Units 11, 12 & 13)
27th Preparatory Tests' Week
28th 3rd Term Paper (Units 9 to 13) ORAL
29th 3rd Term Paper (Units 9 to 13) WRITTEN
30th "
Skylark Science 7 Key Book
141
NOTE : Teachers may synchronize this “Scheme of Study” with our (Term Wise ) “Model Papers”, according to their specific needs.
4th Term
WEEK UNIT # NAME of UNIT PAGE #
31st
1st & 2nd
TERM
(REVISION)
UNITS 1 to 5 4 to 40
32nd " UNITS 6 to 8 41 to 66
33rd
Preparatory Tests' Week (1st & 2nd
Term)
34th
3rd TERM
(REVISION) UNITS 9 & 10 67 to 87
35th " UNITS 11 to 13 88 to 120
36th Preparatory Tests' Week (3rd Term)
37th Preparatory Leaves' Week
38th " 4th Term Paper (Units 1 to 13) ORAL
39th 4th Term Paper (Units 1 to 13) WRITTEN
40th "
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