Question

B cells are tested for their ability to bind to self in the ________ and are removed by ________ if they do bind to self.

A) thymus : apoptosis
B) thymus : phagocytosis
C) bone marrow : phagocytosis
D) bone marrow : apoptosis
E) bone marrow : necrosis

Answer 1

B cells are tested for self-reactivity in the bone marrow and eliminated through apoptosis if they bind to self, ensuring self-tolerance and preventing autoimmunity.

Step-by-step explanation:

B cells are tested for their ability to bind to self in the bone marrow and are removed by apoptosis if they do bind to self. This process is known as central tolerance, which is critical in preventing autoimmunity. B cells that bind too strongly to self-antigens undergo clonal deletion, signaling the cells to induce their own destruction through apoptosis. Those B cells that survive without reacting to self-antigens then proceed to the spleen for further maturation. On the other hand, T cell maturation and testing occur in the thymus, where a similar mechanism of negative selection eliminates T cells that bind strongly to self-antigens through apoptosis.