The carbon cycle

Question 1

what are living things made of?

Answer 1

living things made up material they take from the world around us - plants turn elements like carbon from soil and air into complex compounds = these get passed up the food chain

Question 2

How are these materials returned to the environment ?

Answer 2

by waste products or when an organism dies and decay.

Question 3

Why do materials decay ?

Answer 3

because they’re digested by micro organisms , this happens more in warm, moist , aerobic conditions because microorganisms are more active in these conditions

Decay puts the stuff plants need to grow back into the soil

Question 4

what is the constant cycle in stable communities ?

Answer 4

Materials taken up by soil and used up by plants etc. are balanced by those put back in = constant cycle

Question 5

Cycling of carbon in carbon cycle

Answer 5

1) CO2 removed from green plants and algae during photosynthesis, carbon made by glucose which can be returned as carbohydrates, fats and proteins that make up the body of plants and algae

2) when the plant and algae respire -> some carbon returns to atmosphere as C02

3) When algae and plants eaten by animals, carbon becomes part of fats and proteins in their body which move through the food chain

4) When animals respire = carbon returned to atmosphere as co2

5) When plants, animals, algae die -> other animals and microorganisms feed on their remains, when they respire = co2 returns to atmosphere

6) animals also produce waste which is broken down by detritus feeders and microorganisms

Question 6

What also releases CO2 into the atmosphere

Answer 6

combustion of wood and fossil fuels

Question 7

What does this show?

Answer 7

That carbon is constantly cycled from air, food chain and eventually back into the air again