Answer :
B cell activation and antibody production follow a specific sequence: recognition of antigen, clonal expansion, antibody secretion, and memory cell formation. This order ensures a systematic response where B cells produce antibodies to fight antigens and form memory cells for quicker future responses. The correct sequence is A,B,C,D.
The process of B cell activation and antibody production involves several key steps that occur in a specific order:
- Recognition of antigen: Each naïve B-cell is genetically programmed to create an antibody with a unique antigen-binding site. When an antigen is encountered, its epitopes interact with B-cell receptors on the surface of B-lymphocytes that fit, activating these lymphocytes.
- Clonal expansion: After activation, cytokines produced by helper T cells drive the proliferation of activated B-lymphocytes, leading to the production of thousands of identical cells.
- Antibody secretion: Differentiation of the activated B cells into mature plasma cells occurs, which then start secreting large quantities of antibodies specific to the antigen.
- Memory cell formation: Some of the activated B cells differentiate into memory B cells, which can respond more quickly and effectively upon subsequent encounters with the same antigen.