Answer:
I believe it is convergent boundaries
Explanation:
Sperm cells come from the male
egg cells come from the female
True: because it acts as a semi permeable membrane.
Answer:
Adaptive immune defense system consists of lymphocytes like B-lymphocytes and T- lymphocytes. B-lymphocytes provides humoral immunity while T- lymphocytes provide cell-mediated immunity to the body.
99% of lymphocytes circulate freely in the blood and lymph. B lymphocytes differentiate into plasma B cells and B memory cells when interact with antigen presented by T helper cells.
Then plasma cells secrete antibodies in the circulation which binds to extracellular antigens through antigen-binding site. Then the bounded antigen is recognized by receptors present on phagocytic cells. This receptor binds the Fc region of antigen bounded antibody and destroy the antigen by phagocytosis.
