5.2 Phagocytosis

Question 1

What do phagocytes do?

Answer 1

ingest and destroy invading pathogens (the process is called phagocytosis)

Question 2

Describe the process of phagocytosis.

Answer 2

-pathogens or dead/damaged/abnormal cells release chemical products that act as attractants for phagocytes
-the receptors on the phagocyte’s surface recognise and attach to chemicals on the pathogen’s surface
-the pathogen is engulfed and a vesicle called a phagosome is formed around it
-lysosomes fuse with the vesicle and release lysozymes, hydrolysing the cell walls of ingested bacteria
-soluble products of the hydrolysis of the pathogen is absorbed by the phagocyte

Question 3

What is a phagosome?

Answer 3

the vesicle formed around an engulfed pathogen

Question 4

What is a lysozyme?

Answer 4

enzymes within a lysosome, used to hydrolyse the contents of phagosomes

Question 5

What do phagocytes and lymphocytes have in common?

Answer 5

they are both white blood cells