Question

Question 37:
(a) Explain why, a food chain usually cannot have more than three or four steps.
(b) Calculate the amount of energy that will be available to big fish in the following food chain, if 10,000 J of energy is available to small algae from the sun :
Small algae —-> Zooplankton —-> Fish —-> Big fish

Lakhmir Singh Biology Class 10

Answer 1

Hi

Here devil1407

a) Food chains generally consist of three or four steps ( three or four organisms) because after that the energy available do the next organism will be so small that it will be insufficient to sustain the life of that organism.

b) 0. 1 J

Hope it helps U

Bye

Answer 2

Hey

Here is your answer,

A) The longer the food chain the less raw energy is available to the ones near the top. Energy transfer is at a 10% rate from one level to another. If we start with plants at 100% the next level up will receive 10%. So they have to eat a lot of grass to meet their nutritional needs. The next one up receives 1% and so on. So the longer the food chain the more of that lower level must be eaten to maintain their health and well being. That would mean a very large carnivor would have to eat constantly to amintain their level. This could wipe out all those animals living below them in the chain.

B) o.1 J

Hope it helps you!