(a) Differentiate between humoral immune response and cell-mediated immune response.
(b) Draw a schematic diagram of an antibody molecule and label any four parts.
(b) Draw a schematic diagram of an antibody molecule and label any four parts.
Show Hint
(b) The antibody’s variable region binds to antigens, and its constant region helps in immune cell recognition and activation.
Solution and Explanation
(a) - Humoral immune response: This response involves the production of antibodies by B cells to neutralize pathogens and prevent infections. It is primarily mediated by the action of antibodies in bodily fluids.
- Cell-mediated immune response: This response is carried out by T cells, particularly cytotoxic T cells, which target and destroy infected cells or cancerous cells. It does not involve antibodies.
(b)
- An antibody molecule has a “Y” shaped structure with two heavy chains and two light chains.
- Variable region: Located at the tips of the Y, it binds to the antigen.
- Constant region: The stem of the Y, which determines the class of antibody (IgG, IgM, etc.).
- Hinge region: Located between the arms of the Y, allows flexibility.
- Disulfide bonds: Hold the heavy and light chains together.
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