Phagocytosis

Question 1

What is a phagocyte?

Answer 1

A phagocyte is a type of white blood cell that carries out phagocytosis

Question 2

Is phagocytosis a specific or non-specific response?

Answer 2

It is non-specific as any non-self cell that is detected will trigger the same response to destroy it

Question 3

Describe the phagocytosis of pathogens

Answer 3

1) Chemicals released by pathogens or abnormal cells attract phagocytes
2) The phagocyte recognises the pathogen’s antigens as non-self and the phagocyte binds to the pathogen
3) The phagocyte changes shape and engulfs the pathogen
4) Once engulfed, the pathogen is contained within a phagosome vesicle
5) A lysosome within the phagocyte will fuse with the phagosome and release its hydrolytic enzymes called lyzozymes
6) The lyzozymes digest and destroy the pathogen
7) The phagocyte will then present the digested pathogens antigens on its surface, becoming an APC

Question 4

Why is a phagocyte known as a “antigen-presenting cell” after the process of phagocytosis?

Answer 4

The phagocyte will present the antigens of the digested pathogen on its surface