Question

Which of the following does not describe B-cell receptors?

A. B-cell receptors are membrane bound and secreted.
B. B-cell receptors consist of a variable region and a constant region.
C. B-cell receptors lack specificity and can bind to a number of different antigens.
D. B-cell receptors possess specificity and can therefore bind only to unique epitopes.
E. B cell receptors undergo affinity maturation as a consequence of somatic hypermutation.

Answer 1

B-cell receptors are membrane-bound monomeric forms of IgD and IgM that bind specific antigen epitopes with their Fab antigen-binding regions. They possess specificity and can bind only to unique epitopes. They also undergo affinity maturation through somatic hypermutation.

Step-by-step explanation:

B-cell receptors (BCRs) are membrane-bound monomeric forms of IgD and IgM that bind specific antigen epitopes with their Fab antigen-binding regions. They have a variable region and a constant region, and the variable region provides specificity to the receptor, allowing it to bind to unique epitopes. One of the options, option C, is not correct because B-cell receptors do possess specificity and can bind only to unique epitopes. B-cell receptors do undergo affinity maturation as a consequence of somatic hypermutation, which is a process that improves their binding affinity to antigens over time.