B17- Organising an ecosystem

Question 1

What is a producer?

Answer 1

An organism that photosynthesises and makes its own food

Question 2

Order of consumers in a food chain?

Answer 2

Producers–> primary consumers–> secondary consumers–> tertiary consumers

Question 3

Cycle in levels of prey and predators. Starting with increased food

Answer 3

Plenty of food, prey increases. Plenty of prey for predators, predators increase. More predators eat more prey, so they decrease. Less prey, less food for predators so they decrease. Less prey being eaten so they increase.

Question 4

Decomposers def?
2 examples?

Answer 4

Organisms that break down the waste of dead animals and plants
Bacteria and fungi

Question 5

Key role of decomposers and why its helpful?

Answer 5

-Return nutrients back to the soil
-Used by plants through their roots

Question 6

3 key processes in the water cycle

Answer 6

Evaporation, condensation and precipitation

Question 7

3 key ways in which carbon is cycled? and why?

Answer 7

Photosynthesis- use carbon dioxide from atmosphere
Respiration- carbon dioxide produced as a waste product of respiration
Combustion- burning of food or fossil fuels produces carbon dioxide

Question 8

3 factors that affect the rate of decay

Answer 8

Temperature, moisture levels and oxygen

Question 9

Use of decay?

Answer 9

Creates a natural fertiliser used by farmers

Question 10

What does decay in anaerobic conditions produce?
What can this be used for?

Answer 10

Methane gas
Fuel with the use of biogas generators

Question 11

How to investigate the rate of decay of milk using pH?

Answer 11

-Measure 20cm3 of fresh milk into three beakers
-Label each beaker with a dif temp e.g 5, 20, 30
- Use universal indicator to determine the pH of the milk
-Cover each beaker in cling film and keep at the given temperature
-Use universal indicator to determine the pH of the milk after 24, 48 and 72 hours