Cycles within ecosystem

Question 1

What is the role of photosynthesis in the carbon cycle

Answer 1

Photosynthesis removes carbon dioxide from the atmosphere and stores it in plant biomass

Question 2

How is carbon transferred between organisms

Answer 2

Carbon is passed when herbivores eat plants and carnivores eat other animals

Question 3

How is carbon returned to the atmosphere

Answer 3

Carbon is released as carbon dioxide during respiration in plants animals and decomposers

Question 4

How do decomposers affect the carbon cycle

Answer 4

Decomposers break down dead organisms and release carbon dioxide through respiration

Question 5

How does combustion affect the carbon cycle

Answer 5

Burning fossil fuels releases carbon dioxide into the atmosphere

Question 6

What is nitrogen fixation

Answer 6

Nitrogen fixation converts nitrogen gas into ammonium compounds that can be used by plants

Question 7

Which organisms carry out nitrogen fixation

Answer 7

Nitrogen fixing bacteria in soil and root nodules of legumes convert nitrogen gas into ammonium

Question 8

How do plants absorb nitrogen

Answer 8

Plants absorb nitrates from the soil to build proteins

Question 9

What is nitrification

Answer 9

Nitrification is the conversion of ammonia into nitrites and then into nitrates by nitrifying bacteria

Question 10

What is denitrification

Answer 10

Denitrification is the conversion of nitrates back into nitrogen gas by denitrifying bacteria

Question 11

Why do farmers plough soil

Answer 11

Ploughing increases aeration which reduces denitrification by limiting anaerobic conditions