b1 revision questions

8/16/2019 B1 Revision Questions

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1 It is possible to grow microorganisms in the laboratory.

List A shows some temperatures.

List B shows situations for which these temperatures might be suitable.

Match each temperature to the correct situation. (3)

List A List B

25°C Used in industrial laboratories to growmicroorganisms quickly

35°C Used in school laboratory to growmicroorganisms safely

100°C Used to stop microorganisms growingwithout killing them

Used to kill microorganisms

2 In this question you will be assessed on using good English, organising information clearly and

using specialist term where appropriate.

We need a balanced diet to keep us healthy. Explain the ways in which an unbalanced diet

can affect the body.

...................................................................................................................................

...................................................................................................................................

...................................................................................................................................

...................................................................................................................................

................................................................................................................................... (6)

..

3 A person’s metabolic rate varies with the amount of activity they do.

a Metabolic rate is ................... (1)

Choose one answer.

the breathing rate

the rate of chemical reactions in cells

the heart rate

b Suggest one other factor which can change a person’s metabolic rate.

................................................................................................................................... (1)



4 Polio is a disease caused by a virus. In the UK, children are given polio vaccine to protect

them against the disease.

a Choose the correct words from each list to complete the sentences below.

i It is difficult to kill the polio virus inside the body because the virus

...................................... (1)

is not affected by drugs lives inside cells produces antitoxins

ii The vaccine contains an ................... form of the polio virus. (1)

active infective inactive

iii The vaccine stimulates the white blood cells to produce ................... which destroy the

virus. (1)

antibiotics antibodies drugs

b The graph shows the number of cases of polio in the UK between 1948 and 1968.

i In which year was the number of cases of polio highest?

................................................................................................................................... (1)

ii Polio vaccination was first used in the UK in 1955. How many years did it take for thenumber of cases of polio to fall to zero?

................................................................................................................................... (1)

iii There have been no cases of polio in the UK for many years. But children are still

vaccinated against the disease.

Suggest one reason for this.

................................................................................................................................... (1)

AQA, 2006



5 Controlling infections in hospitals has become much more difficult in recent years.

a Suggest two reasons why MRSA is causing problems in many hospitals.

...................................................................................................................................

................................................................................................................................... (2)

b The pioneer in methods of treating infections in hospitals was Ignaz Semmelweiss. He

observed that women whose babies were delivered by doctors in hospital had a death rate

of 18% from infections caught in the hospital. Women whose babies were delivered by

midwives in the hospital had a death rate of 2%. He observed that doctors often came

straight from examining dead bodies to the delivery ward.

i In a controlled experiment, Semmelweiss made doctors wash their hands in chloride

of lime solution before delivering the babies. The death rate fell to about 2% – down to

the same level as the death rate in mothers whose babies were delivered by

midwives.

Explain why the death rate fell.

...................................................................................................................................

................................................................................................................................... (1)

ii Explain how Semmelweiss’s results could be used to reduce the spread of MRSA in a

modern hospital.

...................................................................................................................................

................................................................................................................................... (2)

AQA, 2005

1 25 °C – Used in school laboratory to grow microorganisms safely,

35 °C – Used in industrial laboratories to grow microorganisms quickly,

100 °C – Used to kill microorganisms

3

2 Marks awarded for this answer will be determined by the Quality of WrittenCommunication (QWC) as well as the standard of the scientific response.There is a clear, balanced and detailed description referring to bothovereating and deficiency. The answer shows almost faultless spelling,punctuation and grammar. It is coherent and in an organised, logicalsequence. It contains a range of appropriate or relevant specialist termsused accurately.

There is some description of a range of the ways in which the diet can beunbalanced and the effects. There are some errors in spelling, punctuationand grammar. The answer has some structure and organisation. The use of

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specialist terms has been attempted, but not always accurately.

There is a brief description of at least two ways in which the diet can beunbalanced, which has little clarity and detail. The spelling, punctuation andgrammar are very weak. The answer is poorly organised with almost nospecialist terms and/or their use demonstrating a general lack of

understanding of their meaning.

No relevant content.

Examples of biology points made in the response:

balanced diet contains all the correct nutrients in the correct amounts

balanced diet has the correct amount of energy

too much energy leads to mass/weight increase e.g. eating too much fat

if activity increases use of energy increases

too little energy leads to decrease in mass/weight

can lead to anorexia/described symptom

lack of vitamins/named vitamin can lead to deficiency

disease/correctly named

too much carbohydrate/ sugar/overweight can lead to type 2 diabetes

lack of a mineral ion/named ion can lead to deficiency

disease/correctly named

obesity linked to e.g. heart disease/arthritis/high blood pressure, etc.

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3 a the rate of chemical reactions in cells 1

b Any one from:

• the proportion of fat to muscle

• inherited factors

• other sensible suggestion, other than activity

1

4 a i lives inside cells

ii inactive

iii antibodies

b i 1950

ii 8 (years)

iii Any one from: e.g.

• disease could be reintroduced (from abroad)

• disease would spread back insufficient

• disease would spread if it came back

• protection on holiday abroad

• high proportion of immune people needed to preventepidemic

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1

1

1

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5 a Any two from:

• resistant to (most) antibiotics

• contagious or easily passed on or reference to open wounds

• patients ill therefore less able to combat disease

2

b i chloride of lime/hand washing killed bacteria (picked up from corpses)allow disease/germs/infection/ disinfectants

ii people to wash hands after contact with patient so bacteria/pathogen/MRSA not transferred to other patient

3



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1 A dog responds to stimuli.

a Link the receptor descriptions to the correct part of the animal by choosing the correct

letter (A, B, C or D).

i Contains receptors to detect chemicals

................................................................................................................................... (1)

ii Contains receptors to detect light

................................................................................................................................... (1)

iii Contains receptors to detect movement of the head and sound.

................................................................................................................................... (1)

b The skin of a human contains receptors which are sensitive to touch.

i Give one other stimulus which is detected by human skin.

................................................................................................................................... (1)

ii Suggest why there are many touch receptors in a person’s fingertips.

................................................................................................................................... (1)

2 a When a person touches a hot surface they move their hand away quickly.

Choose the correct word to complete the sentence.

This is called a ................... action. (1)

learned reflex thoughtful



b What is the importance of this type of action?

................................................................................................................................... (1)

3 This picture shows a Venus fly trap.

a The Venus fly trap catches flies for food. When a fly lands on the leaf the trap closes.

Choose the correct word to complete the sentence.

The shutting of the trap is called a ................... (1)

detector stimulus response

b Suggest one receptor the Venus flytrap has to detect the fly.

................................................................................................................................... (1)

4 Hormones are important chemicals which help to control conditions inside living organisms.

a List A shows three hormones

List B shows where some hormones are produced.

Match each hormone with where it is produced. (3)

List A List B

Hormone Where produced

auxin pituitary gland

oestrogen kidney

FSH plant stems and roots

ovary

b Choose the correct answer to complete each of the following sentences.

i The hormone which causes eggs to mature is .................... . (1)

auxin oestrogen FSH

ii The hormone which causes growth of the uterus (womb) lining is .................... . (1)

auxin oestrogen FSH



5 When light is shone in a person’s eyes they blink. When a plant is placed near a lamp the

stem bends towards the light.

a Choose the correct answer to complete each of the following sentences.

i The response of the eye to bright light is called a ................... action. (1)

learned reflex stimulated

ii The response of the plant to light is called ................... (1)

gravitropism hydrotropism phototropism

b In this question you will be assessed on using good English, organising information clearly

and using specialist terms where appropriate.

Plants respond to light and gravity. Describe how plant hormones control the growth of

roots and shoots.

...................................................................................................................................

...................................................................................................................................

...................................................................................................................................

...................................................................................................................................

...................................................................................................................................

1 a i A

ii C

iii B

b i temperature/pressure/pain

ii idea of increased sensitivity (for a particular task, e.g. to feel a pencilwhen writing)

3

1

1

2 a reflex

b prevents damage/harm OR prevents skin burning

1

1

3 a response

b any one of: touch/pressure/chemical

1

1

4 a Auxin links to plant stems and roots, oestrogen links to ovary, FSH links topituitary gland.

b i FSH

ii oestrogen

3

2

5 a i reflex

ii phototropism

b There is a clear and detailed scientific description of phototropism and

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1

5-6



geotropism and how auxin controls growth of both the root and shoot. Theanswer is coherent and in a logical sequence. It contains a range ofappropriate or relevant specialist terms used accurately. The answershows very few errors in spelling, punctuation and grammar.

There is some description of how hormones cause the root and shoot tobend. The answer has some structure and the use of specialist terms hasbeen attempted, but not always accurately. There may be some errors in

spelling, punctuation and grammar.

There is a brief description of how hormones control growth in either theroot or shoot which has little clarity and detail. The answer is poorlyconstructed with an absence of specialist terms or their use demonstrate alack of understanding of their meaning. The spelling, punctuation andgrammar are weak.



• Correct use of phototropism

• Correct use of gravitropism (allow geotropism)

• Auxin produced in root/shoot

• More hormone/auxin on lower side of root

• More hormone/auxin on lower/dark side of shoot

• Hormone inhibits growth of root cells

• Hormone stimulates growth of shoot/stem cells

• Longer cells on one side

• Causes root/shoot to bend

• Roots grow towards gravity

• Shoots grow towards light.

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1 People take drugs for many different reasons.

alcohol heroin penicillin statin steroid thalidomide

Choose a word from above to match the following sentences.

a an illegal drug which is highly addictive

............................................................................................................................

b a drug used by athletes to make them perform better

............................................................................................................................

c a medical drug which is used to reduce cholesterol levels

............................................................................................................................

2 A drug company wants to test a new painkiller called PainGo2. Thecompany hope that the new drug will cure headaches quicker than

PainGo1.

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PainGo2 has to be tested in clinical trials. PainGo2 is twice as

strong as PainGo1.

Phase 1 trial – a few healthy people will be given one or two tablets

of PainGo2.

Phase 2 trial – a small group (200 –300) of patients with headaches

will be given PainGo2.

Phase 3 trial – 3 large groups (2000 in each group) of patients with

headaches will be given either PainGo2 or PainGo1 or a placebo.

a What is the purpose of the Phase 1 trial?

............................................................................................................................

b Suggest why in Phase 2 the patients were asked to record how

they felt after taking the PainGo2.

............................................................................................................................

c What is a placebo?

............................................................................................................................

d Phase 3 was done as a double-blind trial by doctors who had

patients with headaches.

In a double-blind trial who will know who is given the new drug?

Choose your answer from the choices below.

the patient only

the doctor only

both the doctor and the patient

neither the doctor nor the patient

............................................................................................................................

e Why is it important to use the placebo in the Phase 3 trial?

............................................................................................................................

f Why are some patients given PainGo1 in Phase 3?

............................................................................................................................

3 a Give one example of:



i A legal recreational drug

............................................................................................................................

ii An illegal recreational drug

............................................................................................................................

b Some recreational drugs are addictive.

i Give one example of a recreational drug that is very

addictive.

............................................................................................................................

ii Explain how the action of a drug makes a person become

addicted to it.

............................................................................................................................

c Some doctors think that smoking cannabis causes depression.

Doctors investigated the cannabis smoking habits of 1500

young adults.

The table shows the percentage of cannabis smokers in the

investigation who became depressed.

How many times the menor women had smokedcannabis in the last 12months

Percentage ofmen who becamedepressed

Percentageof womenwhobecamedepressed

Less than 5 times 9 16

More than 5 times, but lessthan once per week

10 17

1 –4 times per week 12 31

Every day 15 68

From the data, give two conclusions that can be drawn about

the relationship between cannabis and depression.

............................................................................................................................

............................................................................................................................

AQA, 2007

4 In this question you will be assessed on using good English,

organising information clearly and using specialist term where



appropriate.

Read the description of an investigation into the link between

smoking cannabis and heroin addiction.

Six ‘teenage’ rats were given a small dose of THC – the activechemical in cannabis – every three days between the ages of 28 and49 days. This is the equivalent of human ages 12 to 18.

The amount of THC given was roughly equivalent to a humansmoking one cannabis ‘joint’ every three days.

A control group of six ‘teenage’ rats did not receive THC.

After 56 days catheters (narrow tubes) were inserted in all twelveof the now adult rats and they were able to self-administer heroin by pushing a lever.

All the rats began to self-administer heroin frequently. After awhile, they stabilised their daily intake at a certain level.

The ones that had been on THC as ‘teenagers’ stabilised theirheroin intake at a much higher level than the others. They appeared

to be less sensitive to the effects of heroin. This pattern continuedthroughout their lives.

Reduced sensitivity to the heroin means that the rats take largerdoses. This has been shown to increase the risk of addiction.

Evaluate this investigation with respect to establishing a link

between cannabis smoking and heroin addiction in humans.

Remember to include a conclusion to your evaluation.

............................................................................................................................

............................................................................................................................

............................................................................................................................

............................................................................................................................

............................................................................................................................

1 a heroinb steroid(s)

c statin(s)

2 a To check for unexpected side effects with the higher dose/stronger painkiller.

b To see if the drug cured the headaches.

c A tablet which does not contain a drug/contains a harmless chemical/ a‘blank’.

d D Neither the doctor nor the patient.

e To rule out psychological effects/description of this.

f To see if the PainGo2/the new drug is better (at curing headaches) thanPainGo1.



1

3 a i tobacco/nicotine/alcohol (accept: solvent/glue/caffeine, ignorecigarettes/coffee)

ii cannabis/heroin/cocaine (allow: crack/weed/ecstasy/LSD/amphetamine/speed/steroids/ GHB).

b i heroin/cocaine/tobacco/nicotine (ignore: alcohol/cigarettes/cannabis/caffeine/coffee)

ii alters body chemistry (ignore: withdrawal symptoms/craving/non-chemical effects on nervous system)

c Any two from:

• increase in cannabis smoking increases (%) depression

• greater effect in women/allow women become more depressed

• depression linked with/not directly caused by cannabis/ignorecannabis causes depression

• not all cannabis smokers get depression.

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4 There is a clear, balanced and detailed argument referring to both pros andcons and a conclusion which matches the pros and cons. The answer showsalmost faultless spelling, punctuation and grammar. It is coherent and in anorganised, logical sequence. It contains a range of appropriate or relevantspecialist terms used accurately.

The answer contains at least one pro and one con with a conclusion. Thereare some errors in spelling, punctuation and grammar. The answer has somestructure and organisation. The use of specialist terms has been attempted,but not always accurately.

There is mention of either a pro or a con with an attempt at a conclusion or alist of pros and cons without a conclusion, has little clarity and detail. Thespelling, punctuation and grammar are very weak. The answer is poorlyorganised with almost no specialist terms and/or their use demonstrating ageneral lack of understanding of their meaning.



Pros, e.g.

• used ‘teenage rats’ as equivalent to human teenagers

• THC dose typical of human cannabis smoking habits• used control group

• rats allowed to choose amount of heroin

Cons, e.g.

• sample size small/only used 12 rats

• heroin administration very different from human situation

Conclusions

• rats given THC/cannabis took more heroin

• (this) is evidence for a link between THC/cannabis and heroin

• (but) rat behaviour/ physiology not necessarily same as

human behaviour/ physiology

• does not prove link in humans.

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!"#: ;4,'.(2) <23 983=(=,-

1 The picture shows a solenodon.

Figure 1 A solenodon

Solenodons have lived on earth since the Age of the Dinosaurs.

They are only found in forests in Haiti and are the only mammals

which have a poisonous bite. They are rarely seen because they

feed at night. They mainly eat insects and spiders.

a The solenodon has adaptations which help it to survive.

Match the adaptation to the correct letter (A, B, C, D or E) to

answer the following questions.

i This helps the solenodon to dig its burrow.

............................................................................................................................

ii This helps the solenodon to detect its food.

............................................................................................................................

b The solenodon is at risk of dying out since new animals have

been taken to the islands.

Use the information and the picture to help answer the following

questions.

i The solenodon is not adapted to flee from predators.

Suggest why.

............................................................................................................................

ii If the solenodon is caught by a predator it can defend itself.

Suggest how.



............................................................................................................................

2 Trees which live in the rain forests are very tall and often have

broad leaves. This is a problem for young trees which do not get

much light.

a Choose the correct answer to complete the sentence.

light nutrients space

Rain forest trees have broad leaves so they can compete for

................... (1)

b Choose the correct answer to complete the sentence.

larger trees large seeds with stored food

Trees in the rain forest have adapted to lack of light near the

ground by having ...................

3 The gemsbok is a large herbivore living in dry desert regions of

South Africa. It feeds on grasses that are adapted to the dry

conditions by obtaining moisture from the air as it cools at night.

The table below shows the water content of these grasses and the

feeding activity of the gemsbok over a 24-hour period.

Time of day % water contentof grasses % of gemboksfeeding

03.00 18 40

06.00 23 60

09.00 25 20

12.00 08 17

15.00 06 16

18.00 05 19

21.00 07 30

24.00 14 50

a i Name the independent variable investigated.

............................................................................................................................

ii Is this a categoric, ordered, discrete or continuous variable?

............................................................................................................................

b How does the water content of the grasses change throughout

the 24 hour period?



............................................................................................................................

c Between which recorded times are more than 30% of the

gemsboks feeding?

............................................................................................................................

d Suggest three reasons why the gemsboks benefit from feeding

at this time.

............................................................................................................................

............................................................................................................................

............................................................................................................................

AQA, 2008

1 a i D

ii E

b i Any one of: Poor eyesight, legs look awkward for running, no naturalpredators, other sensible suggestions.

ii Poisonous bite, has poison, strong claws / description

2 a lightb large seeds with stored food

3 a i Time of day

ii Continuous

b It rises during the night (some time after) 1800 hours to a maximumof 2at 0900 hours and then falls (more rapidly at first) to a minimum of 5% a1800 hours

Some accurate reference to actual figures in the table is necessary toobtain the mark.

c Between 2400 hours and 0600 hours. The important words here are

‘more than’. Candidates who ignore these words will include the figure of 30% and therefore give a response of 2100 hours to 0900 hou

d The water content of the grasses that it eats are high over thisperiod.

It is night and the gemsboks are therefore less easily seen by predators

It is cooler and therefore they are less likely to have to sweat and so thihelps them conserve precious water.



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1 Rabbits eat very large amounts of grass. A single hawk eats a few

rabbits.

a Draw a pyramid of biomass for the rabbits, grass and the hawk.

b Much of the energy from the grass is not transferred to the

hawk.

Suggest two reasons why.

............................................................................................................................

............................................................................................................................

2 Choose words from below to complete each sentence.

carbon dioxide cool dry insects microorganisms

a Plant waste in a compost heap is decayed by ....................

b The plant waste decays faster in conditions which are

................... and ...................

c The plant waste will also decay faster when the air contains

plenty of ................... .

3 The diagram shows what happens to the energy in the food a calf

eats.

In the calculations show clearly how you work out your answer.



a Calculate the % energy lost in methane (X).

............................................................................................................................

............................................................................................................................

b The energy in the food the calf eats in one day is 10

megajoules.

Calculate the amount of this energy that would be lost in faeces

and urine.

............................................................................................................................

............................................................................................................................

c Name the process which transfers the energy from the food into

movement.

............................................................................................................................

d The farmer decides to move his calf indoors so that it will grow

quicker.

Suggest two reasons why.

............................................................................................................................

............................................................................................................................

4 In this question you will be assessed on using good English,


appropriate.

The constant cycling of carbon in nature is called ‘The carboncycle’.

Each autumn, trees lose their leaves.

Describe how the carbon in the leaves is recycled so that the trees

can use it again.

............................................................................................................................

............................................................................................................................

............................................................................................................................



............................................................................................................................

............................................................................................................................

5 The diagram shows a pyramid of biomass drawn to scale.

a What is the source of energy for the water plants?

............................................................................................................................

b The ratio of the biomass of water plants to the biomass of

insects is 5:1.

Calculate the ratio of the biomass of insects to the biomass of

frogs.

Show clearly how you work out your answer.

............................................................................................................................

............................................................................................................................

c Give two reasons why the biomass of the frog population is

smaller than the biomass of the insect population.

............................................................................................................................

............................................................................................................................

d Some insects die.

Describe how the carbon in the dead insect bodies may berecycled.

............................................................................................................................

............................................................................................................................

............................................................................................................................

............................................................................................................................



1 a Pyramid drawn with three layers

widest to narrowest either way up but correctly labeled.

b Any two from:

• not all the grass eaten is used to make rabbit grow / waste in ureafaeces / roots not eaten

• energy is lost due to movement by rabbits /rabbits run around

• energy used to keep rabbits warm• hawks do not eat the whole rabbit

2 a microorganisms

b moist and warm (either order )

c oxygen

3 a 10 (%)

if wrong answer allow 25+35+30 for 1 mark

b 2.5 if incorrect answer allow 1 mark for correct working.

c respiration

d It reduces the calf’s movement because it won’t walk about, therefore it

use that energy for growth. It also reduces the energy the calf will need tuse to keep warm and that energy can be used for growth.reduces movement/walking about reduces energy/transferred byheating/keeps (calf )warm.

4 There is a clear and detailed description of the sequence of events in thcarbon cycle. The answer is coherent and in a logical sequence. Itcontains a range of appropriate or relevant specialist terms usedaccurately. The answer shows very few errors in spelling, punctuation angrammar.

There is some description of the sequence of events in the carbon cycle but

there is a lack of clarity and detail. The answer has some structure and tuse of specialist terms has been attempted, but not always accurately.There may be some errors in spelling, punctuation and grammar.

There is a brief description of the carbon cycle, which has little clarity andetail. The answer is poorly constructed with an absence of specialistterms or their use demonstrates a lack of understanding of their meaningThe spelling,

punctuation and grammar are weak.


Examples of biology points made in response:

• microorganisms – only allow once if no mention of bacteria or fungi

• bacteria

• fungi

• digest / break down organic matter / leaves / decompose / reference

decomposers / decay / rot

• respiration

• combustion

• release of carbon dioxide

• into the air

• CO2 can be used (by trees) in photosynthesis

• reference to faster in warmer weather / slower during the

winter/cold weather.



5 a the sun / light / sunshine / solar

allow radiation from the sun

ignore photosynthesis / respiration

apply list principle

do not allow water / minerals / heat

b 2.5 (:1)

correct answer with or without working

ignore rounding with correct working

do not allow other equivalent ratios for both marksevidence of selection of 10 (insects)and 4 (frogs) or 50 and 20 or 1 and 0.4 for 1 mark

if no other working allow 1 mark for (1): 0.4 on answer line

c Any two from:

allow for insects or frogs

allow energy for biomass

• some parts indigestible / faeces

• waste / examples of waste, e.g. urea / nitrogenous compounds / urine /excretion

• movement / e.g. of movement

allow keeping warm• heat

• not all eaten / e.g. of not all eaten

• respiration

do not accept energy for respiration

d Any four from:

• (bodies) consumed by animals / named / scavengers / detritus feeders

• microorganisms / bacteria / fungi / decomposers

• reference to enzymes

• decay / breakdown / decompose / rot

ignore digest(ion)

• respiration

• carbon dioxide produced

• photosynthesis

• sugar / glucose produced

accept other organic molecules

• fossilisation / fossil fuels / named

• combustion / burning

must be linked with fossilisation / fossil fuels

• (burning) produces carbon dioxide

allow carbon dioxide produced once only

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.&7+)2-2*/

1 Strawberries are able to reproduce many plants from one parent

plant.

Choose the correct answer to complete each sentence.

a Producing new plants with one parent is called ....................asexual reproduction genetic engineering sexual

reproduction



b The advantage of this is that all the strawberry fruits will

.................... (1)

be bigger all taste better all taste the same

c A disadvantage of this to the strawberry plants is that

.................... (1)

there is more variation they are genetically identical they

cannot mate

2 Read the passage. Use the information and your own knowledge to

answer the questions.

At one time, the boll weevil destroyed cotton crops. Farmers sprayedthe crops with a pesticide.

The weevil died out but another insect, the bollworm moth, becameresistant to this pesticide.

In the 1990s large crops of the cotton plant were destroyed by the bollworm moth. The pesticides then used to kill the moth wereexpensive and very poisonous, resulting in deaths to humans.

Scientists investigated alternative ways to control the bollworm moth.

They found out that a type of bacterium produced a poison whichkilled bollworm larvae (grubs).

A GM cotton crop plant was developed which produced the poison to

kill bollworms. This proved to be very effective and farmers were ableto stop using pesticide sprays.

Now farmers have another problem. Large numbers of other insectshave multiplied because they were not killed when the farmersstopped using pesticides. Some of these insects have started to destroy

the GM cotton and farmers are beginning to use pesticides again!

a i Give one advantage of spraying crops with pesticides.

............................................................................................................................

ii Give two disadvantages of spraying crops with pesticides.

............................................................................................................................

............................................................................................................................

iii Give one economic advantage of using GM cotton.

............................................................................................................................

iv Some people object to using GM crops. Suggest one

reason why.

............................................................................................................................



b In this question you will be assessed on using good English,


appropriate.

The GM cotton was genetically engineered to produce the same

poison as the bacterium.

Describe fully how this is done

............................................................................................................................

............................................................................................................................

............................................................................................................................

............................................................................................................................

............................................................................................................................

............................................................................................................................

3 The use of cloned animals in food production is controversial.

It is now possible to clone ‘champion’ cows.

Champion cows produce large quantities of milk.

a Describe how adult cell cloning could be used to produce a

clone of a ‘champion’ cow.

............................................................................................................................

............................................................................................................................

............................................................................................................................

............................................................................................................................

b Read the passage about cloning cattle.

The Government has been accused of ‘inexcusable behaviour’

because a calf of a cloned American ‘champion’ cow has been born on a British farm. Campaigners say it will undermine trustin British food because the cloned cow’s milk could enter thehuman food chain.

But supporters of cloning say that milk from clones and their

offspring is as safe as the milk we drink every day.Those in favour of cloning say that an animal clone is a geneticcopy. It is not the same as a genetically engineered animal.Opponents of cloning say that consumers will be uneasy about



always accurately. There may be some errors in spelling, punctuation andgrammar.

There is a brief description of the genetic engineering, which has littleclarity and detail. The answer is poorlyconstructed with an absence of specialist terms or their use demonstratesa lack of understanding of their meaning. The spelling, punctuation andgrammar are weak.


Examples of biology points made in response:

• gene from the bacterium

• is cut from the chromosome

• using enzymes

• gene transferred to the cotton

• (cotton) chromosome – allow cell

• (the gene) controls characteristics

• causes the cotton (cells) to produce the poison.

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8 a Any four from:

• nucleus / DNA / chromosomes / genetic material removed (from egg)

• from (unfertilised) egg / ovum linked to second point

allow ‘empty egg cell’ for first two marks

do not allow fertilised egg

allow egg from champion cow

• nucleus from body cell of champion (cow)

• inserted into egg / ovum

• electric shock

• to make cell divide or develop into embryo

• (embryo) inserted into womb / host / another cow

allow this point if wrong method e.g. embryo splitting

b Any four from:

Pros: Max 2 marks

• economic benefit e.g. increased yield / more profit

• clone calf not genetically engineered

• genetic material not altered

• milk safe to drink / same as ordinary milk

Cons: Max 2 marks

• consumer resistance• caused by misunderstanding process

• not proved that milk is safe

ignore ‘God would not like it’ or ‘it’s not natural’

• ethical / religious argument

• reduce gene pool / e.g.

Conclusion: Max 1 marks

sensible conclusion for or against, substantiated by

information from the passage and / or own knowledge

conclusion at end

4

5



!"#H A=2-8.(2)

1 a This diagram shows a timeline for the evolution of some

dinosaurs. The mass of each dinosaur is shown in the brackets

by its name.

Choose the correct answer to complete each sentence.

Dinosaur evolution timeline

i A dinosaur which lived between 100 and 150 million years

ago is .................... .

Agilisaurus Saturnalia Tyrannosaurus

ii Camarasaurus evolved from ................. .......... .

Agilisaurus Alamosaurus Saturnalia

iii The difference in mass between Agilisaurus and the

smallest dinosaur is ....... kg.

1.82 5.5 7.32

b i The earliest life forms developed on Earth more than

3 ................... years ago.

billion million thousand

ii The earliest life forms can be described as ...................

bony complex simple

c Darwin suggested a theory of evolution. His theory is described

as evolution by ......................................

acquired characteristics a god natural selection

2 Giraffes have developed their long necks over millions of years.



Two scientists tried to explain why the giraffes have long necks.

They are called Darwin and Lamarck.

Match the name in List A to the correct statement in List B.

List A List B

Name Statement

Darwin only Noticed that the neck of the giraffetime

Lamark only Had enough evidence to prove whyneck got longer

Both Lamark andDarwin

Thought that natural selection workin neck length present at birth

Thought the giraffe stretched its neleaves in trees. Then its young inheneck

3 The photograph shows a snake eating a toad.

Cane toads were first introduced into Australia in 1935. The toads

contain toxins and most species of Australian snake die after eating

the toad. The cane toad toxin does not affect all snakes the same

way. Longer snakes are less affected by toad toxin. Scientists

investigated how red-bellied black snakes had changed in the 70

years since cane toads were introduced into their area. They found

that red-bellied black snakes had become longer by around 3 –5%.

Suggest an explanation for the change in the body length of the red-

bellied black snakes since the introduction of the cane toads.



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AQA, 2005

1 a i Agilisaurus

ii Saturnalia

iii 7.32

b i billion

ii simple

c Natural selection

2 Darwin only – Thought that natural selection worked on variations in necklength present at birth.

Lamark only – thought the giraffe stretched its neck while eating leaves intrees. Then its young inherited the longer neck. Both Lamark and Darwin – noticed that the neck of the giraffe changed over time.

3 Accept any four from:

• mutation (do not accept ‘had to mutate / decided to mutate’)

• produces longer snake or there is variation in snake length (do not accept ‘had to adapt and became longer’)

• longer snake less susceptible to toxin or longer snake survives• survivors reproduce

• gene passed to next generation (allow characteristic passed to nextgeneration)

b1 revision questions

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