AP BIOLOGY

Detailed explanation-1: -The flow of energy in food chain in unidirectional because the sun is the only source of energy for all ecosystems on earth. Then the energy is captured by the autotrophs does not revert back to the sun. Therefore, in the food chain, the energy moves progressively through various trophic levels.

Detailed explanation-2: -Trophic Levels. Energy flows through an ecosystem in only one direction. Energy is passed from organisms at one trophic level or energy level to organisms in the next trophic level.

Detailed explanation-3: -To show the flow of energy through ecosystems, food chains are sometimes drawn as energy pyramids. Each step of the pyramid represents a different trophic level, starting with primary producers at the bottom. The width of each step represents the rate of energy flow through each trophic level.

Detailed explanation-4: -Ecological pyramids show the relative amounts of matter or energy in different trophic levels of an ecosystem. In most ecosystems, only about 10% of the total energy available at a given trophic level is transferred to the next level.

Detailed explanation-5: -Energy flows through an ecosystem in a one-way stream, from primary producers to various consumers. A food chain is a series of steps in which organisms transfer energy by eating and being eaten.