Organisation of an Ecosystem

Question 1

How can feeding relationships be represented?

Answer 1

With a food chain

Question 2

The food chain:

Answer 2

1) Producer
2) Producers eaten by primary consumers
3) Primary consumers (prey) are eaten by secondary consumers (predators)
4) Secondary consumers are eaten by tertiary consumers

Question 3

What are producers?

Answer 3

• They are always photosynthetic organisms (green plant/algae).
• Through photosynthesis they make glucose
• They make up the biomass

Question 4

How can you work out the distribution and abundance of species in an ecosystem?

Answer 4

With tools called transects (a path) and quadrats (a grid)

Question 5

Population dynamics:

Answer 5

• If the population of prey increases, so will predators.
• After some time, prey will decrease as more would be consumed by the increased predators.
• When there isn’t enough prey to feed predators, the population of predators will decrease, allowing prey to increase again.

Question 6

The carbon cycle:

Answer 6

1) Carbon is removed by producers who use it in photosynthesis.
2) By eating plants, animals consume carbon compounds.
3) Carbon is released into the atmosphere (as carbon dioxide) because of respiration in plant and animal cells.
4) When animals and plants die, decomposers return the carbon back into the atmosphere when they decay.

• Combustion of fossil fuels is another source of releasing carbon

Question 7

The water cycle:

Answer 7

1) Water evaporates from the Earth’s surface, before rising up into the atmosphere.
2) The water vapor cools and condenses into precipitation, which returns to the Earth’s surface.
3) This either becomes either surface runoff or will become ground water.
4) Plants take up water through their roots