AP BIOLOGY

Detailed explanation-1: -All owls are predators; they depend on other animals for food. However, very few predators feed on owls (except sometimes other owls). In fact, owls often eat other predators, such as weasels, bats, shrews and insect-eating birds. Therefore, owls hold a position at the top of the food chain.

Detailed explanation-2: -Primary producers use energy from the sun to produce their own food in the form of glucose, and then primary producers are eaten by primary consumers who are in turn eaten by secondary consumers, and so on, so that energy flows from one trophic level, or level of the food chain, to the next.

Detailed explanation-3: -Food Chains In a grassland ecosystem, a grasshopper might eat grass, a producer. The grasshopper might get eaten by a rat, which in turn is consumed by a snake. Finally, a hawk-an apex predator-swoops down and snatches up the snake.

Detailed explanation-4: -The food chain is the sequence of population or organisms through which food and its contained energy pass in an ecosystem with members at one step becoming the food of later step of the sequence. Energy flow is always unidirectional. Energy flows progressively from one trophic level to another and cannot revert back.