B1.6 Waste materials from plants and animals

Question 1

What is bacteria?

What does it do?

Answer 1

• Single celled microscopic organism

- It causes decay by releasing enzymes which break down compounds in their food so it can be absorbed by their cells

Question 2

What is fungi?

What does it do?

Answer 2

• Often larger organisms that include moulds and mushrooms

- It causes decay by releasing enzymes which break down compounds in their food so it can be absorbed by their cells

Question 3

What are the conditions for decomposition? (3)

What happens for each?

Answer 3

• Temperature
  Speeds up decomposition but when its too hot he enzymes will die and denature and won’t break the material down
• Moisture levels
  The more moisture it increases decomposition bacteria multiply
• Oxygen
  It will increase the rate of decomposition

Question 4

What is the carbon cycle?

Answer 4

Fossils fuel are burnt which puts carbon dioxide in the air
Plants use the carbon dioxide for photosynthesis
These plants feed the animals which then they all die to organic compounds in dead organisms adding more carbon dioxide to the atmosphere when they decompose

Question 5

What impacts the carbon cycle? (3)

Answer 5

• Deforestation = less carbon dioxide
• Burning fossil fuels = more carbon dioxide
• Soil degradation (over farming) = no nutrients in soil for plants to grow and take in carbon dioxide