Neurological - by nerves
Endocrinological - by blood and secrets
B. Global warming accelerates the greenhouse effect
During the process of biological magnification , the concentration of pollutants, such as DDT or mercury, is multiplied as it passes up a food chain.
Answer:
peptide antigens by MHC class II molecules
Explanation:
Helper T cells are activated by peptide antigens by MHC class II molecules. These antigens express on the surface of antigen-presenting cells (APCs). After activation, the T helper cells divide and secrete cytokines to assist the immune response.
