Explain the classification of marine organisms?

These are mainly classified on the basis of region of their activity. They can be plankton, nekton or benthon. The plankton occurs in the surface layer of aquatic habitat. It may float or drift passively. It moves along with the water currents as they lack locomotory organs. They may have locomotory organs but they are not strong. They are also referred as microscopic organisms. The neuston is referred as large organisms. The plankton is divided into the phytoplankton and zooplankton. The phytoplankton means photosynthetic plankton and the zooplankton means phagotrophic plankton. The nektons are the organisms which have well developed and strong locomotory organ. It helps them to swim actively and in the deep waters also. They are phagotrophic and feed on the plankton or nekton. The benthon organisms occur at the bottom of sea. They can be sessile or creeping. They can be crawling also. They mainly include the scavengers and decomposers.