MODULE 5 PART 2.2: STAGES OF PHAGOCYTOSIS

Question 1

In Activation Stage, when neutrophils are triggered, they mount what actions?

Answer 1

• Respiratory burst
• Release elastase, defensins, and oxidants

Question 2

What are the stages of phagocytosis?

Answer 2

1. Activation
2. Chemotaxis
3. Adherence and Opsonization
4. Ingestion
5. Destruction

Question 3

In Activation Stage, what cytokine will attract more neutrophils?

Answer 3

TNF-a

Question 4

Stage of phagocytosis where directed migration of neutrophils occur; crawling toward the area with the highest concentration

Answer 4

Chemotaxis stage

Question 5

In Chemotaxis stage, what serves as attractants for neutrophils?

Answer 5

• Peptides
• Chemokines
• Lipids

Question 6

In Chemotaxis stage, chemoattractant receptors are concentrated in one end of neutrophil stage. True or False?

Answer 6

False

Question 7

In Adherence & Opsonization stage:

Since both cells and bacteria are suspended in body fluids and usually have a negative charge and so repel each other, what should the body do?

Answer 7

The charge of the bacteria should be neutralized by coating it with a positively charged molecules

Question 8

In Adherence and Opsonization stage, what are the molecules that coat bacteria to promote phagocytosis?

Answer 8

Opsonins

Question 9

What are the 2 types of phagocytosis?

Answer 9

• Antibody receptor-mediated (type 1)
• Complement-mediated (type 2)

Question 10

In Adherence and Opsonization stage:

This is a phenomenon where bacterium lodges in tissues or trapped between neutrophil and another cell surface can be readily ingested. What do you call this?

Answer 10

Surface phagocytosis

Question 11

In Ingestion stage,

Neutrophils have a ____ that advances first toward a chemotactic source followed by the main portions of the cell.

Answer 11

pseudopod