It may be a lake, a marsh, a spring or a glacier. This is where the stream starts. The source is the farthest point of the river stream from its estuary or its confluence with another river or stream. ... The farthest stream is called the headstream or headwater.
Answer:a
Explanation:
because there is special use for it
Pollution :) Since Abiotic means non living.
Bacteria: Living
Food (worms or smaller fish): Living
Predators: Living
Pollution (dirt, trash, or other stuff): Non Living
The correct answer is (c) discover antigens in body fluids.
B lymphocytes act as antigen presenting cells that recognizes and displays the antigen to the white blood cells. These cells process the antigens that are present in body fluids. Professional antigen presenting cells includes B-lymphocytes, macrophages, dendritic cells, etc.
