Functioning Ecosystems

Question 1

Define biomass

Answer 1

amount of organic matter in a system (density)

Question 2

How much of solar energy is absorbed by plants?

Answer 2

1%

Question 3

Differentiate between the two types of consumers.

Answer 3

Specialists - consumers that eat a limited range of things (Koalas)
Generalists - eat variety of food (bandicoot)

Question 4

Differentiate between detritivores and decomposers

Answer 4

detritivores - ingest and digest nutrient internally (worms)

decomposers - external digestion, often excrete enzymes to break down nutrients to absorb (bacteria, fungi)

Question 5

Why do food chains rarely have more than 5 trophic levels?

Answer 5

Due to loss of energy as only 10% of energy is passed between trophic levels

Question 6

What is productivity?

Answer 6

rate at which energy is added to the bodies of organisms in form of biomass

Question 7

What is gross primary productivity (GPP)?

Answer 7

rate at which solar energy is captured in sugar molecules during photosynthesis. Producers (plants) use some of this energy for metabolism/ cellular respiration and some for growth

Question 8

What is net primary productivity (NPP)?

Answer 8

GPP minus rate of energy loss to metabolism and maintenance.