ICAR AIEEA PG Fisheries Science 09 July 2023 (Shift 1) Paper

Ecotoxicological terminology for pollutant dynamics:

• Bioconcentration is the direct net accumulation of a chemical directly from water into an aquatic organism via respiratory surfaces and skin, excluding dietary uptake.
• Bioremediation is the use of microorganisms to degrade or neutralize toxic pollutants.
• Biomagnification (biological magnification) refers specifically to the progressive increase in the tissue concentration of persistent, non-biodegradable lipophilic contaminants (such as DDT, PCBs, and methylmercury) as they pass successively through higher trophic levels of a food chain.
• Biotransformation is the biochemical modification of foreign chemicals (xenobiotics) by enzyme systems in living organisms.

Subdivisions of ecological science:

• & (D) Autecology (species ecology) is the study of the ecological relations of an individual organism or single species with its environment.
• Population ecology focuses specifically on dynamics within a single interbreeding population of one species.
• Synecology (community ecology) is defined as the scientific study of the interactions, structure, and dynamics between whole multi-species biological communities (groups of different species coexisting in a given area) and their physical environment.

Geographical distribution of major ocean currents:

• The Agulhas Current is a prominent warm, fast-flowing western boundary current of the Southwest Indian Ocean that flows southward along the east coast of southern Africa.
• The Canary Current is a cold eastern boundary current in the North Atlantic Ocean flowing southward along northwest Africa.
• The Kurile Current (Oyashio Current) is a cold subarctic ocean current in the northwest Pacific Ocean.
• The Florida Current is a warm thermal ocean current flowing through the Florida Straits in the Atlantic Ocean, merging into the Gulf Stream.