Second Semester Review

Biotic factors

• Factors that are living or come from living organisms.• Examples:

• Tree• Wooden toothpick• Paper

Abiotic factors

• Factors that are non-living, do not come from living organisms.• Examples:

• Soil (rocks too)• Air (climate, weather)• Water (solid, liquid or gaseous water)• Sunlight (light, temperature)

Levels of organization

• Smallest to largest- organism, population, community, ecosystem, biome, biosphere.

• Organism-Single member of species• Population- Members of a species in a

region• Community- Different species interacting

with one another in a specific area.• Ecosystem- Biotic and abiotic factors in a

given area.• Biome-interacting ecosystems in a region.

• Biosphere- the part of Earth that supports life.

Classification

• Heterotrophic/ Autotrophic (TEKS 6.12D)*• Heterotrophic/ Autotrophic

• Heterotrophic- gets nutrition from an outside source• Examples are anything that eats: consumers, animals, bacteria, fungi

• Autotrophic- self feeder; makes own food through photosynthesis or chemosynthesis

• Examples are producers; plants and some acheaebacteria

Classification

• Unicellular/Multi-cellular (TEKS 6.12D)*• Organisms are composed of one or more cells: Unicellular/ Multi-

cellular• Unicellular- one celled organisms; the individual organism is made up of only

one cell like bacteria.• Multi-cellular- many celled organisms; the organism is made up of many cells

working together like humans. • Cellstissuesorganssystemsorganism

Classification

• Mode of Reproduction (TEKS 6.12D)*• Sexual reproduction

• Sex cells are created through meiosis• makes 4 daughter cells with half the genetic information

• Needs the genetic information of two parents to create a unique organism allowing for more genetic variation.

• • Asexual reproduction

• Requires the genetic material of only one parent • Offspring is genetically identical to the parent • Types of asexual reproduction:

• Budding – organism grows out of the adult• Binary fission- like mitosis, occurs in bacteria• Parthenogenesis- whip tail lizards in New Mexico are all females and lay eggs that hatch to be clones of the mother.• Regeneration- The regrowth of a missing limb, like lizard tails and starfish.

Life – the basic unit of all life is the cell. All organisms are made up of one or more cells.Prokaryotic cells 1. Do not have a nucleus, have a

primitive loose genetic material.2. Do not have membranes

around cell parts.3. Always Unicellular (single

celled) organisms like Eubacteria and Archaebacteria.

4. Reproduce asexually

Eukaryotic cells5. Have a nucleus6. Have membrane bound cell parts.7. Protista, Fungi, Plantae, Animalia are

kingdoms composed of eukaryotic organisms.

8. Can be unicellular or multicellular9. Can reproduce sexually or asexually

The three DOMAINSArchaea• Kingdom Archaebacteria• Single celled• Prokaryotic(no nucleus)• Very primitive• Asexual reproduction

through binary fission.• Live in extreme

environments like: hot springs, around deep sea volcanic vents, mineral rich water. Cannot live in oxygen.

Bacteria• Kingdom Eubacteria• Single celled • Prokaryotic(no nucleus)• Asexual reproduction

through binary fission.• Live in the soil, water, air

and inside living organisms.

Eukarya• Kingdoms:

• Plant• Animal• Protista • Fungi Have nucleus in cellCan be multicellular or unicellular.Are Eukaryotic (cells have nucleus)

Kingdom Plantae • Are eukaryotic (cells have a nucleus)• Majority are multicellular, reproduce sexually (pollination)or asexually

(budding).• Autotrophic (makes own food)

• Have chloroplast

Kingdom Animalia• Are eukaryotic (cells have a nucleus)• Heterotrophic (get nutrition from outside sources)• Multicellular• Majority reproduce sexually (50% of the DNA comes form one parent

and 50% from the other parent.

Kingdom Fungi• Eukaryotic (nucleus)• Heterotrophic

• Get their nutrients from decaying matter

• Unicellular or multicellular• Can reproduce sexually or

asexually

Kingdom Protista

• Eukaryotic• Majority are Unicellular, very few

are multicellular• Have characteristics of plants and

animals• Autotrophs and/or heterotrophs• Asexual reproduction through

• Budding, regeneration

• some reproduce sexually

Atoms- basic building block of all matter,the smallest whole unit of matter.

Atomic number is the number of protons in the nucleus of an atom.

In a normal atom, the atomic number = the number of protons = the number of electrons.

Protons and neutrons are found in the nucleus of an atom.Electrons are found orbiting the nucleus in energy shells.

Charge

Periodic tableMetalloids

Properties of Metals• Malleable• Ductile• Shiny • Good conductors of

heat and electricity

Properties of non-Metals• Brittle solids• Dull• Mostly gases • Poor conductors of

heat and electricity• Good insulators

Properties of Metalloids• Have characteristics of

both metals and non metals

• semiconductors

A chart that organizes the elements according to size (mass)and physical and chemical properties.

Elements comprise Earth (TEKS 6.5B)

How many elements are in the following compounds? • Hint- count the capital letters. Each symbol should have only one capital letter. The

symbol is the element’s abbreviation and it’s used in chemical formulas. Elements have only one to three letters in their symbols but only one is a capital letter.

• H2PO4

• CO2

• H2O• C6H11O2

• NH3

How many elements in the following chemical reaction?

CO2 + H2O C6H11O2 + O2

Matter

• Elements• A substance consisting of atoms

which all have the same number of protons - i.e. the same atomic number. Elements are chemically the simplest form.

• Examples: gold, copper, carbon, aluminum, oxygen, hydrogen, etc.

• The symbol is one letter as in H, O, C, or two letters as in He, Ca, Ne, Cl

• Compounds • Substances made of two or more

different kinds of atoms chemically bound together.

• Examples: water, salt, sugar, carbon dioxide, baking soda

• The formula has letters and numbers: H2O, NaCl, CO2

Physical properties of matter

1. Can be identified just by observing matter. You do not have to change it in any way.

2. Can be things you identify with your senses, such as, sight, touch, taste, smell, or hearing.

3. Include things such as color, texture, shape, mass, odor, state of matter, freezing point, boiling point, density, etc.

Review Physical Properties (TEKS 5.5A)

• Properties that can be measured or seen through direct observation, include;

• Size • Color • Luster • Density • Mass • Volume • Length • Texture

• State (S,L,G) • Malleability• Magnetism • Specific gravity• Conductivity• Temperature • Hardness • Cleavage • Fracture

Examples of physical properties

• The way the squishy stuff stretches out

• The way a rubber ball bounces• The way ice cream melts• The sweet taste of candy• The heaviness of a rock• The rough texture of sandpaper• The height of a building• The hardness of a mineral, its

streak, • Magnetism

Density

• The amount of matter in a given volume• D=mass/volume

High density Medium density Low density

Liquid Mass (g)

Volume (mL)

Density(g/mL)

A 20.0 10.0

B 5.0 25.0

C 30.0 30.0

After calculating the density of the three liquids, can you predict the order the liquids will be in if you used them to create a density tower?Which liquid would be on the top? Explain.Which would be on the bottom? Explain.

Physical states of matter Solids• Have a definite shape • Have definite volume• The atoms are really close

together.

Liquids• Have indefinite shape• Have definite volume• The atoms are loosely held

together.

Gases• Have indefinite shape • Have indefinite volume• The atoms are far apart from

each other.

Physical change

• Phase Change – aka change in state of matter – a PHYSICAL CHANGE• Melting point – solid state to liquid state (heat is added)• Boiling point – liquid state to gas state (heat is added)• Freezing point – liquid state to solid state (heat is removed)• Condensation point – gas state to liquid state (heat is removed

Chemical properties of matter

1. You have to change matter in some way to identify a chemical property.

2. You cannot tell about chemical properties by just using your senses.

3. Includes things such as flammability, acidity, alkalinity, being poisonous, etc.

How do you know when a chemical change has occurred? • What evidence can you look for?

• The new substance starts fizzing or bubbles.

• The new substance heats up without external help.

• The new substance gets cold without you adding ice to it.

Chemical change = Chemical reaction

Examples of chemical properties

•The flammability of paper, gasoline, alcohol.•The way iron rusts when left outside.•The way copper tarnishes to green over time (statue of liberty).

•The way apples, bananas, and avocadoes turn brown when sitting out in the air.

Used to identify matter

Chemical Properties

Used to identify matter without changing the substance.Density, melting point, boiling point, freezing point, state of matter (S,L,G,P). Things that you can see, hear, smell, touch, taste, size, shape, color, odor, weight, mass, texture, sweetness.

Physical Properties

How matter interacts with other matter.Can be identified only after a change has occurred in the substance. Such as:Acidity, alkalinity, ability to rust, ability to tarnish, ability to burn.

Energy

• The ability to cause change• Example: “I get lots of energy from a chocolate chip cookie.”

States of energy• Potential Energy – energy that is

stored in an object because of its position or chemical composition.

• Examples: • P- a rock sitting on a ledge• P- a rollercoaster car at the top of

the track• C- a battery waiting to be used• C- a can of gasoline

• Kinetic Energy- energy that is being used in the motion of something.

• Examples:• A rock rolling down a hillside• A rollercoaster car going around the

track.• A person running around a track.

Forms of energy1. Chemical energy- calories in food, acid in a battery, can of gasoline.2. Solar/radiant energy(light)- sunlight, light from a bulb, glow of hot

metal.3. Heat/thermal energy- from friction, from steam, from hot stove.4. Sound energy-vibrations from a speaker, thunder.5. Electrical energy- lightening, current in the wires.6. Mechanical energy- motion of machine parts, motor, or engine.7. Nuclear energy- nuclear fission reactions like at a nuclear power

plant, nuclear fusion reactions like inside a star.

How an Electrical Power Plant Works

1. We use the chemical energy in a fossil fuel (coal or oil) to make heat.

2. The heat is used to make steam.3. The steam is turned into

mechanical energy in the turbo generator.

4. The mechanical energy is changed into electrical energy in the turbo generator.

Sources of Electric Power1. Fossil fuels – oil or coal is burned to heat water that turns into steam, that spins the turbine,

and runs the generator. can be built anywhere. cause air pollution and there is a limited amount of them

2. Hydroelectric power- water rushes from behind the dam and spins the turbine to run the generator. No air or water pollution. not all places have deep enough rivers.

3. Nuclear power- heat from nuclear radiation from the reaction boils water and the steam runs the generator. can be built anywhere, no smoke or gases into the air. radiation, and it requires a lot of water that becomes unusable.

4. Geothermal- steam from a hot spring runs the generator. no air or water pollution. not all places have hot springs.

5. Wind power- the wind turns the blades of the wind turbines and runs the generator. No air or water pollution. Not all places have enough wind.

6. Solar Power- light striking the silicon cells of the panel causes a flow of electrons. No generator is needed. No pollution or shortage of sunlight. Night and cloudy days.

Force- a push or a pull with a certain strength and direction, anything that can change the motion of an object.Examples:• Friction• Gravity• Wind• Magnetism• Water• Muscle power

Balanced forces are equal in strength, so they don’t cause motion or a change in motion if the object is moving. Unbalanced forces are NOT equal in strength and that causes motion. It moves the object in the same direction as the stronger force.

Balanced and unbalanced Forces• Balanced forces

no motion

• Unbalanced forces

motion

motion

The object moves in the direction of the strongest force.

Displacement

• The distance and direction between your starting point and your ending point.

10 miles NE

The distance you walk on a winding path can be much greater than the displacement.

Speed – displacement over time

• Distance(D) divided(/) by time(t). S=D/t. Often measured in a unit of distance per unit of time. Example miles per hour (mph).

• What is the speed of a car traveling 1000 meters in 50 seconds?• How long would it take a meal worm to travel 5 meters across the

ground if it’s traveling at 0.25 m/s?

Velocity- speed and direction

Velocity has magnitude and direction

Acceleration

• Any change in speed or direction. This includes slowing down as well as speeding up, and changing direction.

• Examples: a Car coming to a stop. A car taking off from a stop. A car turning a corner. Racing. Roller-coaster ride.

Newton’s 1st law• An object at rest stays at rest and an object in motion stays

in motion, unless an unbalance force acts upon it.• This is linked to inertia (an objects resistance to a change

in its motion.• Examples:

• A truck sitting in a parking space until you start the engine and make it move.

• A train moving 100mph down a track until the brakes make it stop.

• Which object has more inertia? 10 g 50g

Newton’s 2nd Law• An object moves in the same direction as a force that is

pushing or pulling on it.• The object changes direction to go with the force applied

to it or changes its speed to go with the force applied to it. • It accelerates in the same direction as the force applied on

it. • Examples:

• Earth’s gravity pulling a meteor into the atmosphere. (it speeds up as gravity pulls on it)

• A paper airplane goes in the direction you push it.• A magnet pulling a paper clip toward itself using its magnetic

force.

Newton’s 3rd Law

• For every action there is an equal and opposite reaction.

• Two forces are involved and the are opposite to each other

• Examples: • A person

jumping on a trampoline

• Bouncing a ball

• A rocket launching into the air

Simple machines

• Inclined Planes/Pulleys (TEKS 6.8E) • Investigate how inclined planes and pulleys can be used to change

the amount of force to move an object• Inclined plane-

Pulley systems