B2b

Question 1

Where does energy come from at the start of a food chain, and how else is energy passed on

Answer 1

Th energy first comes from sunlight, plants (producers) use this in photosynthesis. All other organisms get their energy from other organisms (consumers)

Question 2

Food chains can be linked to form….

Answer 2

Food webs; these show different tropic (feeding) levels. Energy is passed from one organism to the next; one tropic level to the next

Question 3

What is a herbivore, omnivore and a carnivore

Answer 3

A herbivore is an animal who only eats plants
An omnivore is an animal that eats both plants and meat (other animals)
A carnivore is an animal that only eats other animals

Question 4

What is a pyramid of biomass

Answer 4

A pyramid to show tropic levels by using an organisms dry mass (estimated or only possible with dead animals)

Question 5

What is a pyramid of numbers

Answer 5

A pyramid to show trophic levels through the number of actual organisms at each level

Question 6

Why does the number of animals and plants in a food web constantly change

Answer 6

When the number of one species changes, it can effect every other species in the chain

Question 7

How much energy is lost at each trophic level, and how is it lost

Answer 7

Up to 90% - through respiration, egestion and excretion; however some of these (decomposes) can be used to start a different food chain

Question 8

Why is the length of a food chain limited to 3 or 4 links

Answer 8

Because there wouldn’t be enough energy to sustain any more organisms, and would depend upon the earlier food links being uninterrupted

Question 9

What is the equation for the efficiency of energy transfer

Answer 9

(energy used for growth (output)) / (energy supplied (input)) x 100

Basically; (energy used / energy given) x 100

Question 10

What do food chains show

Answer 10

The energy transfer each time an organism is eaten