6.3.1 b biomass transfer through an ecosystem

Question 1

What is the source of energy for almost all ecosystems on Earth?

Answer 1

the sun

Question 2

What are food webs?

Answer 2

Systems of interlinked food chains

Question 3

What do food chains and food webs show?

Answer 3

Transfer of biomass and energy through the organisms in an ecosystem

Question 4

Define tropic level

Answer 4

Each stage in the chain

Question 5

What is the first level on the chain?

Answer 5

Producer

Question 6

Define producer

Answer 6

An organism that converts light energy into chemical energy by photosynthesis

Question 7

Define consumer

Answer 7

Organisms that obtain their energy from feeding on other organisms

Question 8

Why do food chains rarely have consumers past the quaternary consumer?

Answer 8

Not sufficient biomass and stored energy left to support any further organisms

Question 9

Define decomposer

Answer 9

Break down dead organisms releasing nutrients back into the ecosystem

Question 10

What does a pyramid of numbers show?

Answer 10

Each level represents the number of organisms at each tropic level

Question 11

Define biomass

Answer 11

Mass of living material present in a particular place or in particular organisms

Question 12

How do you calculate biomass at each trophic level?

Answer 12

Multiply the biomass present in each organism by the total number of organisms in that trophic level

Question 13

How do you measure biomass?

Answer 13

Calculate the dry mass of organisms present
Organisms have to be killed to be dried
They are placed in an oven at 80 degrees until all water has evaporated

Question 14

What are the units of biomass in land and water?

Answer 14

Grams per square metre
Grams per cubic metre