Question

During a humoral immune response, which of the following happens when a pathogen is recognized?

Answer 1

I believe the answer is B. The antibodies on B cells bind to the antigens on the pathogen's surface.

Answer 2

Answer:

Memory B cells divide to form plasma cells that surround the pathogen.

Explanation:

Acquired immunity is gained after birth and is usually pathogen specific. When our body encounters the pathogen for the first time, the response produced is called primary response, which is weak or we can say of low intensity. During subsequent attacks the response produced is called secondary response which is quick and of high intensity.

Both primary and secondary immune response is due to two types of cells called B-cells and T-cells.  These cells provide two types of acquired immunity:

1. Humoral immunity: The B-cells produce an army of proteins is response to the pathogen. On encountering the pathogen, B-cells differentiate into plasma cells that secrete antibodies into our blood. Undifferentiated B-cells remain as memory cells.

2. Cell mediated immunity: It is mediated by T-cells. T cells do not produce antibodies but they help B cells to produce them. Some T cells differentiate into helper T cells which help activating the B cells to produce antibodies.