T cells and B cells can be activated only by
A) pathogens.
B) interleukins, interferons, and colony-stimulating factors.
C) cells infected with viruses, bacteria, or cancer cells.
D) exposure to a specific antigen at a specific site in a plasma membrane.
E) disease-causing agents.

Question

Quizplus · Accepted Answer

T cells and B cells require exposure to a specific antigen at a specific site in a plasma membrane to be activated. This is known as antigen recognition and is the basis of the adaptive immune response. Antigens can come from pathogens, infected or cancerous cells, or foreign substances like chemicals or drugs. However, simply being exposed to disease-causing agents or immune system signaling molecules like interleukins and interferons is not enough to activate T and B cells.

T Cells and B Cells Can Be Activated Only by