Question

M cells are:

A. macrophages found in the mucosa
B. antigen-transporting cells from the lumen to the lamina propria found in the mucosa
C. phagocytic cells found in the brain
D. a form of activated B-cells that secrete antibody
E. follicular dendritic cells found in the mucosa

Answer 1

M cells are specialized cells found in the mucosa of the small intestine that play a crucial role in the immune response. They take up antigens from the intestinal lumen and transport them to Peyer's patch, where they are presented to other immune cells. M cells help protect the body from pathogens.

Step-by-step explanation:

M cells are specialized cells found in the mucosa of the small intestine. They are responsible for taking up antigens from the intestinal lumen and transporting them to the underlying tissue called Peyer's patch. These antigens are then presented to antigen-presenting cells such as dendritic cells, which activate T cells and B cells to mount an immune response.

For example, when a pathogen enters the intestinal lumen, M cells sample the pathogen and excrete it into a pocket formed by the inner surface of the cell. This pocket contains antigen-presenting cells like dendritic cells, which engulf the antigens and present them to other immune cells.

Overall, M cells play a crucial role in the immune response of the mucosal tissues in the small intestine, helping to protect the body from potential pathogens.