4.3.1 Water Cycle & Carbon Cycle

Question 1

Where do Water molecules move?

Answer 1

between various locations – such as rivers, oceans and the atmosphere – by specific processes

Question 2

How is it possible for water Molecules to move between various locations?

Answer 2

because water changes state at a relatively low temperature

Question 3

What does water enter the atmosphere as?

Answer 3

as water vapour in one of two processes

Question 4

What are the 2 processes for water vapour

Answer 4

1. Energy from the Sun heats the Earth’s surface and water evaporates from oceans, rivers and lakes

Question 5

The warmer air of the lower atmosphere rises, what does it do with the water vaper?

Answer 5

taking the water vapour with it

• The moist air cools down as it rises
• Water vapour condenses back into liquid water, forming clouds

Question 6

Water returns to earth in the form of, what?

Answer 6

precipitation

Question 7

As the water droplets in the cloud get bigger and heavier, they begin to fall as rain, snow and sleet, what is this called?

Answer 7

precipitation

Question 8

Exam Tip

Answer 8

Make sure you can identify each of these water cycle processes on a diagram as this is a common multiple choice question.

Question 9

Nutrients such as carbon and nitrogen are not, what?

Answer 9

endless resources

Question 10

There is a finite amount of each element on the planet and as such, what needs to happen to them?

Answer 10

they need to be recycled in order to allow new organisms to be made and grow

Question 11

Carbon is taken out of the atmosphere in the form of, what?

Answer 11

carbon dioxide by plants to be used for photosynthesis

Question 12

Carbon is passed on to, what?

Answer 12

animals (and microorganisms) by feeding

Question 13

Carbon is returned to the atmosphere in the from of, what?

Answer 13

in the form of carbon dioxide by plants, animals and microorganisms as a result of respiration

Question 14

What happens if animals and plants die in conditions where decomposing microorganismes are not present?

Answer 14

the carbon in their bodies can be converted, over millions of years and significant pressure, into fossil fuels

Question 15

When fossil fuels are burned (the process is known as combustion), what happens?

Answer 15

the carbon combines with oxygen and carbon dioxide is released into the atmosphere

Question 16

Increased use of fossil fuels is contributing, to what?

Answer 16

to an increase in the carbon dioxide content of the atmosphere

Question 17

What is mass deforestation reducing?

Answer 17

the amount of producers available to take carbon dioxide out of the atmosphere by photosynthesis

Question 18

deforestation is taking place for land rather than for the trees themselves, and as such they are burnt down, what does this affect?

Answer 18

releasing yet more carbon dioxide into the atmosphere

Question 19

Exam Tip

Answer 19

The carbon cycle is simple:

• Carbon is taken out of the atmosphere by photosynthesis
• It is passed on to animals and decomposers by feeding

-It is returned by respiration; in plants, in animals and in decomposing
microorganisms

• In addition, it is returned (in increasing amounts) by combustion of fossil fuels

You should be able to identify what each arrow represents in any diagram of the carbon cycle.