Secondary Non-Specific Defences Flashcards Preview

4.1 Communicable Diseases > Secondary Non-Specific Defences > Flashcards

Flashcards in Secondary Non-Specific Defences Deck (20)
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1
Q

What is an antigen-presenting cell?

A

A cell that isolates the antigen from a pathogen and places it on the plasma membrane so that it can be recognised by other cells in the immune system.

2
Q

What is clonal selection?

A

Selection of a specific B or T cell that is specific to the antigen.

3
Q

What is cytokinesis?

A

Hormone-like molecules used in cell signalling to stimulate the immune response.

4
Q

What is a neutrophil?

A

A type of white blood cell that engulfs foreign matter and traps it in a large vacuole (phagosome), which fuses with lysosomes to digest the foreign matter.

5
Q

What are opsonins?

A

Proteins that bind to the antigen on a pathogen and then allow phagocytes to bind.

6
Q

When are secondary defences used?

A

Secondary defences are used to combat pathogens that have entered the body.

7
Q

What are antigens?

A

Chemical markers on the outer membrane of a pathogen which the body uses to recognise that it is foreign.

8
Q

What are opsonins a type of?

A

Antibody

9
Q

What is the role of the opsonin?

A

To enhance the ability of phagocytic cells to bind and engulf the pathogen.

10
Q

What id the first line of secondary defence?

A

Phagocytosis

11
Q

What are neutrophils?

A

They are the most common type of phagocyte.

12
Q

Where are neutrophils made?

A

In the bone marrow.

13
Q

What do neutrophils do?

A

They engulf and digest pathogens.

14
Q

What is pus?

A

The collection of dead neutrophils that contain bacteria.

15
Q

What are macrophages?

A

Play an important role in initiating the specific responses to invading pathogens.

16
Q

What do macrophages travel in the blood as?

A

Monocytes

17
Q

What happens when a macrophage engulfs a pathogen?

A

It does not fully digest it. Instead the antigen from the surface of the pathogen is saved and moved to a special protein complex on the surface of the cell.

18
Q

What is the macrophage called once it has kept the antibody on the surface of it’s membrane?

A

An antigen-presenting cell.

19
Q

Why is a special protein complex needed by the macrophages?

A

So that it doesn’t get recognised as foreign and start getting attacked by other phagocytes.

20
Q

What is the role of antigen-presenting cells?

A

To increase the chance that the antigen will come into contact with them.