AP BIOLOGY

Detailed explanation-1: -The base of the pyramid is composed of species called autotrophs, the primary producers of the ecosystem. All other organisms in the ecosystem are consumers called heterotrophs, which either directly or indirectly depend on the primary producers for food energy.

Detailed explanation-2: -At the bottom of the pyramid, you have producers. These are usually plants or other photosynthetic organisms, such as algae or photosynthetic bacteria. Producers are autotrophs, meaning they are self-feeding organisms that do so by making their own organic molecules.

Detailed explanation-3: -The bottom and largest level of the pyramid is the producers and contains the largest amount of energy. As you move up the pyramid, through the trophic levels to primary, secondary and tertiary consumers, the amount of energy decreases and the levels become smaller.

Detailed explanation-4: -The first and lowest level contains the producers, green plants. The plants or their products are consumed by the second-level organisms-the herbivores, or plant eaters. At the third level, primary carnivores, or meat eaters, eat the herbivores; and at the fourth level, secondary carnivores eat the primary carnivores.

Detailed explanation-5: -In a food web, producers are placed in the lowest trophic level since they are able to produce their own food. Examples of producers include plants and algae. Consumers, which could either be herbivores or carnivores, occupy the higher tropic levels.