AP BIOLOGY

Detailed explanation-1: -Nekton are all organisms that swim actively in open water, independent of currents. Benthos are bottom-dwelling organisms of the sea or ocean and are often attached to hard surfaces.

Detailed explanation-2: -Epifauna. Epifauna live attached to hard surfaces such as rocks, shells, and pilings or directly on the surface of the Bay’s bottom. Epifauna include oysters, sponges, sea squirts, sea stars, and barnacles. An oyster reef is an example of an epifaunal benthic community.

Detailed explanation-3: -Benthos or benthic organisms live on the ocean floor, either on the substrate (epifauna and epiflora) or inside it, buried or burrowing in the sediment (infauna). Benthic organisms may be sessile, attached to a firm surface such as rocks and manmade structures, or mobile, moving freely on or in the bottom sediment.

Detailed explanation-4: -Animals that live on the sea floor are called benthos. Most of these animals lack a backbone and are called invertebrates. Typical benthic invertebrates include sea anemones, sponges, corals, sea stars, sea urchins, worms, bivalves, crabs, and many more.

Detailed explanation-5: -Organisms confined to bottom are called as benthos. Pelagic organisms are differentiated into plankton (microscopic, drifting over surface), neuston (macroscopic, floating, or swimming on or near water surface), nektons (actively swimming inside water).