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Flashcards in B2b-energy flow Deck (14)
1

what is a trophic level?

a feeding level
Position occupied by a group of organisms in a food chain

2

What is a producer?

Organisms that make their own food
Eg lettuce -sunlight

3

What is a primary consumer?

Eat consumers
First consumers

4

What is a secondary consumer?

Eat first consumers

5

What does a pyramid of biomass show?

Shows the mass of living material at each stage of the food chain

6

Why is it difficult to measure dry biomass?

You have to kill the organism first to dry out all the water

7

Why is it difficult to construct an accurate pyramid of biomass?

Some organisms feed at more than one trophic level

8

Why can pyramids of biomass and pyramids of numbers be different shapes?

Pyramids of biomass mostly pyramid shape
Pyramid of numbers-number of organisms

9

How does energy from the sun flow through food webs?

Plants use some light energy from sun to make food

10

What is egestion?

When food that can't be digested passes out as faeces

11

How is energy or material lost at each stage?

Respiration
Energy lost as heat to surroundings
Excretion
Egestion

12

What happens to waste products and uneaten parts?

They can become starting points for other food chains

13

Why do most food chains have no more than five trophic levels?

Material and energy lost at each stage of food chain
Not enough energy to support more organisms

14

What is the efficiency of energy transfer?

How good it is at passing on energy from one level to the next