Cycles

Question 1

explain the carbon cycle

Answer 1

• Animals respire producing CO2 into the air
• Dead plants and animals get broken down my decomposers, releasing CO2
• plants take in CO2 through photosynthesis
• burning fossil fuels release carbon back into the atmosphere

Question 2

explain the water cycle

Answer 2

1) precipitation returns water to the earth
2) Some evaporates and some enters rivers into the sea
3) some filters into the ground
4) water evaporates from the sea and from plants when they transpire
5) This condenses as it rises into clouds.

Question 3

explain the nitrogen cycle

Answer 3

1) decomposers break down decaying matter including animals and plants into ammonium
2) Nitrifying bacteria turn ammonium compounds into nitrates
3) -some is absorbed by plants roots
- some is released into the air by denitrifying bacteria
4) plants get eaten by animals
5) nitrogen gas in the air gets turned into nitrates by nitrogen fixing bacteria or in root nudules