NEET BIOLOGY

Detailed explanation-1: -Changes in community structure arise due to both internal processes (termed autogenic forces), such as competition among species, the accumulation of peat, or herbivory, and external (allogenic) factors, such as natural or anthropogenic disturbances (e.g., floods or nutrient enrichment).

Detailed explanation-2: -A keystone species is an organism that helps define an entire ecosystem. By keeping populations of mussels and barnacles in check, this sea star helps ensure healthy populations of seaweeds and the communities that feed on them-sea urchins, sea snails, limpets, and bivalves.

Detailed explanation-3: -Keystone species will keep several of the prey populations below the carrying capacity of the community. Keystone species will increase species diversity within the community. If the keystone species is removed from the community, the community structure can collapse.

Detailed explanation-4: -Habitat area and stability, resource availability, and species interactions are major factors that affect community structure.