Question

the energy and biomass decrease from lower to higher levels so there are rarely more than ______ trophic levels in a food chain. a 3 b 2 c 1 d 4

Explanation:

In a food chain, energy transfer between trophic levels follows the 10% rule (only about 10% of energy is passed from one level to the next). With each transfer, a large amount of energy is lost (as heat, for maintenance, etc.). As a result, after 4 - 5 trophic levels, the energy available is too low to support a higher - level consumer. So, there are rarely more than 4 trophic levels.

Answer:

d. 4