Select the correct statement (s) about the transfer of food energy up the trophic levels from its source in autotrophs.

Select all that apply.

An organism feeds at only one trophic level.

The length of a food chain is limited by the inefficiency of energy transfer along the chain.

Few plants have adaptations to reduce feeding by herbivores.

1 - False

2 - True

3 - True

Explanation:

All plants, for example, occupy the same trophic level (producers) as all herbivorous animals (primary consumers). However, not all animals always occupy the same trophic level. This is the case of carnivores or omnivores, for example, who may be consumers of different orders. So the first statement is false.

The flow of energy in an ecosystem's food chain is always unidirectional, and at each trophic level, the less energy available to the next level. This explains the fact that chains tend not to be very large, usually with five or fewer links. Given this, the second statement is true.

Some plants have a variety of mechanisms that protect them from being eaten by herbivores, such as high levels of leaf or stem toxicity, as well as the presence of thorns. This concludes that the third statement is true.