PATHOLOGY

Detailed explanation-1: -Antigens are substances (usually proteins) on the surface of cells, viruses, fungi, or bacteria. Nonliving substances such as toxins, chemicals, drugs, and foreign particles (such as a splinter) can also be antigens. The immune system recognizes and destroys, or tries to destroy, substances that contain antigens.

Detailed explanation-2: -Definition. An antibody is a protein component of the immune system that circulates in the blood, recognizes foreign substances like bacteria and viruses, and neutralizes them.

Detailed explanation-3: -Membrane-bound immunoglobulin on the B-cell surface serves as the cell’s receptor for antigen, and is known as the B-cell receptor (BCR). Immunoglobulin of the same antigen specificity is secreted as antibody by terminally differentiated B cells-the plasma cells.

Detailed explanation-4: -Antigens are any substance that the immune system can recognize and that can thus stimulate an immune response. (B lymphocytes) are white blood cells that produce antibodies specific to the antigen that stimulated their production.