Year 7 EXAM REVISION QUESTIONS
Why is your ecological footprint a different size from other people’s?
What have chains and webs got to do with food?
Provide an example of each of the following.
1.
An abiotic factor
2.
A biotic factor
3.
A species
4.
An ecosystem
Outline the relationship between ecosystems, abiotic factors and biotic factors.
Distinguish between: abiotic and biotic factors
List five biotic and abiotic factors that are part of the ecosystem in which you live.
Which organisms trap the energy from the sun?

Identify the source of energy for all ecosystems on Earth.
Why do food chains rarely contain more than three levels of consumer?
What is a pollutant? Give three examples of pollutants.
In the food chain below, which organism is the third-order consumer?
Grass

grasshopper

frog

snake
A Grass
B Grasshopper
C Frog
D Snake
Examine the figure below and identify the abiotic and biotic factors in the environment shown.

Genevieve and Callum made some observations over a period of a week about the feeding habits of a number of organisms in a small pond. Their results are listed below.

Snails eat water plants and algae.

Tadpoles eat algae.

Small fish eat snails, algae and water plants.

Larger fish eat snails, small fish and tadpoles.
Construct a food web using the information above. Start with the producers at the bottom and work upwards. Make sure your arrows face the right way.
1.
Which organisms are the producers?
2.
Which organisms are first-order consumers?
3.
Which organisms are both second- and third-order consumers?
4.
Which organism is an omnivore?
5.
Which organisms are predators of the snail?
6.
Which organisms are competitors of the tadpoles?
7.
What would happen to the water plants and the larger fish if the snails increased in number?
8.
What would happen to the snails and the larger fish if the small fish disappeared?
Use the information below to answer the questions that follow.
The aquatic organisms that inhabit the intertidal zone of the ocean experience a variety of effects from abiotic and biotic environmental factors caused by the changing low and high tides. At times of low tide, animals find refuge in moist burrows or in the confines of their shells. Sea snails are equipped with a trapdoor-like appendage called an ‘operculum’ which traps oxygen-rich water in their shell during low tide. Alternatively they can move to nearby rock pools or anchor themselves to a rock, which has the same effect as the trapdoor. It is at low tide that animals inhabiting the intertidal zone are most vulnerable to predators of all kinds, including man.
(a) Define the term abiotic.

(b) List the abiotic factors that would affect the organisms in the ecosystem at low tide.
(c) Name a biotic factor experienced by animals in the ecosystem at low tide but not high tide.
(d) Why are plants referred to as producers?
(e) Explain how aquatic algae fit the same description.
Complete the tasks below using the following information.

Insect larvae eat grass.

Honeyeater eats insect larvae.

Hawk eats honeyeater and rabbits.

Thrush eats insect larve.

Cat eats thrush and honeyeater.

Rabbit eats grass.
(a) Create two food chains.

(b) Combine two or more food chains to make a food web.
(c) Circle producers in green, herbivores in blue, carnivores in red and omnivores in black.
(d) Make a table and list all predators and prey (remember that some organisms may fit into more than one category).
Bacteria and fungi belong to an ecosystem group called:
A composers.
B decomposers.
C plants.
D. herbivores.
As you move up the food web:
A the number of organisms increases.
B the number of organisms decreases.
C the number of organisms stays the same, but the size of each gets bigger.
D the number of organisms stays the same, but the size of each gets smaller.
As energy flows through a food web:
A some of it is destroyed.
B all of it is eventually destroyed.
C some is lost to the environment.
D it is divided equally between each type of organism.

Label the following diagram of the water cycle using the following words: condensation, evaporation, precipitation.
Which of the following terms is best used to mean ‘close to extinction’?
A Rare
B Vulnerable
C Endangered
D Suspect
On the following pyramid, label each level using the following words: carnivores, producers, herbivores.

Match the terms related to ecosystems with their definitions on the right. Place the correct letter to the left of each number.
…… 1.
1 Abiotic A The place where an organism lives
…… 2.
2 Biotic B The loss of a complete species. A species becomes extinct when the last organism of the species dies.
…… 3.
3 Ecosystem C Organisms such as bacteria and fungi that break down the matter of dead organisms so that it can be returned to the soil, air and water
…… 4.
4 Habitat D An organism that relies entirely on other organisms for its food
…… 5.
5 Autotroph E A system of living and nonliving things that interact with and depend upon each other
…… 6.
6 Heterotroph F An animal that is hunted by other animals for food
…… 7.
7 Producer
…… 8.
8 Consumer
…… 9.
9 Scavengers
…… 10.
1 Decomposer
…… 11.
1 Herbivore
…… 12.
1 Carnivore
…… 13.
1 Omnivore
G
H
I
J
K
L
An animal that eats plants and other animals
Describes living parts of an ecosystem
Animals that eat dead plant and animal material
A diagram, beginning with a producer or producers, that shows what organisms eat
An organism that makes its own food using energy from an outside source, usually the sun
An organism that feeds on other organisms
M Describes the different levels in a food chain, food web or food pyramid
…… 14.
1 Predator N Describes a species that is not native to an ecosystem; it has been brought in from another ecosystem
…… 15.
1 Prey
…… 16.
1 Food chain/web
O
P
An organism that makes its own food, such as plants, phytoplankton and certain bacteria
Describes the non-living parts of an ecosystem
…… 17.
1 Trophic level Q An animal that hunts other animals for food
…… 18.
1 Endangered species R An animal that eats other animals and plants
…… 19.
1 Extinction S An animal or plant that is under the threat of extinction
…… 20.
2 Introduced T An animal that eats only plants

CHAPTER 4: Ecosystems
Worksheet 4.2
Science Quest 7: pages 122 –127
Many animals eat more than one type of food. This means that they are in more than one food chain.
Add arrows to the diagram below to join a number of food chains together to produce a food web. Note that some animals, such as the seagull, may actually be in more than one level, depending on which chain you follow to the top. A food web also has decomposers. Decomposers are organisms, such as bacteria, worms and fungi, that break down dead animals and plants. The nutrients in the dead animals and plants are recycled back into the food web.
Herbivores, such as the green turban snail, eat the plants and are called first-order consumers.
Carnivores, such as the dog whelk, that eat first-order consumers are known as second-order consumers.
The seagull is a third-order consumer because it eats the second-order consumer.
Octopus
Seagull
Dog whelk
Crab
Shrimp
Dead and decaying material
Zebra fish
Green turban
Snail
Blenny
Seaweed and algae
Limpets


How do geologists know where to mine for precious minerals?
From a damp green swamp to a lump of coal — how does that happen?
What makes underground coal-mining so dangerous?
How many homes can be powered by a single wind generator?
How does global warming affect the water cycle?
Decide whether each of the following natural resources are renewable or non-renewable.
Coal
Diamonds
Hydro-electricity
Natural gas
Water
Wind energy
Wood
Why are minerals in the Earth's crust classified as non-renewable resources?
Which minerals can be detected because of their magnetic properties?
From where does the energy stored in fossil fuels come?

What happens to the energy stored in fossil fuels when they are burned?
How does oil and natural gas get trapped underground?
List two ways of ensuring that the Earth's supply of non-renewable energy resources doesn't run out.
Describe two ways in which solar energy can be used to generate electricity.
Identify a non-renewable fuel that is not a fossil fuel.
Each of the renewable energy options for generating electricity solves some of the problems caused by burning fossil fuels. However, each of them also has disadvantages. Describe the disadvantages of each of the renewable energy options.
Renewable energy source
Solar
Wind
Biomass
Ocean waves
Tidal
Geothermal
Hydro-electricity
Disadvantage
Which renewable energy options involve the use of heat from the sun? ( Hint: There is more than one answer.)
Nuclear energy is a non-renewable energy source.
1) Why is it classified as non-renewable?
2) Is nuclear energy a fossil fuel? Give a reason for your answer.

Where is most of the water on Earth found?
What causes sea water to evaporate?
What are clouds and how do they form?
Tick the box that is correct
Description
Is a renewable resource
Is a sustainable energy option
Uses energy from the sun
Is a fossil fuel
Can be used to generate electricity
Contributes to global warming
Causes chemical pollution
Coal
Nuclear energy
Hydroelectricity
Natural gas
Solar energy
Wind energy
The diagram below shows two oil and gas traps.
The porous rock is called a ‘reservoir rock’. Explain what this means.

Examine the following graphic and answer the questions.
(a) Explain the meaning of the vertical arrows in the diagram.
.............................................................................................
.............................................................................................
(b) Identify the physical process that occurs at the surface of the sea.
.............................................................................................
.............................................................................................
(c) Identify the physical process that occurs at the top of the arrows in the air.
.............................................................................................
.............................................................................................
.............................................................................................
(d) Explain the importance of the sun in this process.
.............................................................................................
.............................................................................................
.............................................................................................
To assist you:

Worksheet 7.2
1.
Write the words in the correct spot in the diagram below to explain the movement of water through the water cycle. Include the following words in your annotations: clouds condensation evaporation infiltration sun ocean surface run-off precipitation transpiration
2.
In your own words, explain how the water cycle operates.
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...............................................................................................................................................................
...............................................................................................................................................................
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What causes the seasons?
Why is there more daylight in summer than winter?
Why does the same side of the moon always face the Earth?
What causes the phases of the moon?
Why do coastal communities experience high and low tides?
Why are total solar eclipses so rare?
Explain the difference between the revolution and rotation of the Earth
How long does it take the Earth to complete one: a) rotation b) revolution
During which season does Australia tilt towards the sun?
Explain why it is usually warmer on a summer's day than on a winter's day.

Use the diagram below to answer the following questions.
1.
Which of the locations A, B, C, D and E:
1.
are in daylight
2.
are experiencing summer
3.
will experience the longest day
4.
will experience the shortest day?
2.
In which of the locations that are in daylight will the sun set first?
During which phase of the moon is it: a) between the sun and the Earth b) on the opposite side of the Earth from the sun
What is a lunar month?
Why is the phase in which half the moon is visible called a quarter moon?
What is the major cause of tides on Earth?
Why are there two high tides and two low tides in a day?
Even though the sun is much larger than the moon, it has much less effect on the tides. Why?
Explain the difference between a solar eclipse and a lunar eclipse.

Explain why total solar eclipses are much less frequent than partial solar eclipses.
The diagram below shows half the Earth in sunlight while the other half is in darkness.
Which Australian season is represented in this diagram?
Explain how you know.
Sketch the shape of:
(a) a crescent moon
(b) a gibbous moon
(c) a full moon.

1.
Number the pictures below to show the correct order of the moon’s phases.
What does the gravitational pull from the moon cause?
Explain why we cannot see the moon when it is between the sun and the Earth.
Identify which of the pictures below represents a solar eclipse and which represents a lunar eclipse.
Justify your answers.

In the diagram below, indicate whether points A, B, C and D are examples of high tide or low tide.
Identify how spring and neap tides differ from normal low and high tides.
The measure of the force that gravity exerts on an object is called and can be measured with a spring scale.
The force acts in the direction opposite to the force of gravity, so it makes an object feel lighter.
1.
balanced
2.
buoyant
3.
gravitational
4.
opposite
3. The strength of gravity between two objects depends on and .
4. The force of attraction between any two objects that have mass is called .
What does Earth's gravity do?
1.
Allows ships to sail smoothly.
2.
Keeps things from floating away from Earth.
3.
Pulls the Earth closer to the sun each year.
4.
Causes volcanoes to erupt.
The rise and fall of water on earth is caused by
1.
the moon's gravity.
2.
the earth's axis tilting.
3.
the moon phases.
4.
changes in the weather

The pull that planets and other objects have on each other is called what?
1.
torque
2.
arc
3.
rotational pull
4.
gravitational pull
The force of gravity on a person or object at the surface of a planet is called
1.
mass
2.
gravity
3.
weight
What is the acceleration of gravity?
1.
1.8 m/s2
2.
5 m/s2
3.
9.8 m/s2
4.
8.9 /ms2
Why is gravity so important?
1.
Because it keeps us from falling into space.
2.
Because it keeps us on earth.
3.
Because without it we wouldn't have an atmosphere.
4.
All of the above.
is the measure of the force of gravity on an object
1.
mass
2.
weight
3.
density
4.
equation
What is the measurement of gravity pulling on an object?
1.
mass
2.
gram
3.
weight
4.
kilogram
The response of an object to the force of gravity is called
1.
volume
2.
mass
3.
weight
4.
density
The strength of the force of gravity between two objects depends on
1.
only the shapes of the objects.
2.
only the masses of the objects.
3.
only the distance between the objects.
4.
both the masses of the objects and the distance between them.