5.2 Phagocytosis

Question 1

What are the two types of white blood cells?

Answer 1

• lymphocytes
• phagocytes

Question 2

What is phagocytosis?

Answer 2

When large particles, such as bacteria, can be engulfed by cells in vesicles formed from the cell-surface membrane.

Question 3

What are the 5 main stages of phagocytosis?

Answer 3

1) phagocyte is attracted and moves to the pathogen by chemical products
2) phagocyte attaches its several cell-surface receptors onto surface of pathogen
3) phagocyte engulfs the pathogen, it is now a phagocyte
4) lysosomes release lysozymes, hydrolyse pathogen (e.g. bacterium)
5) pathogen is broken down and waste products exit cell via exocytosis

Question 4

What is the vesicle called once the phagocyte engulfs the pathogen?

Answer 4

Phagosome