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Flashcards in THE IMMUNE SYSTEM Deck (68)
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1

What is an infection

interaction between a pathogen and the bodys defence mechanisms

2

What is immunity

the body being bettwe prepared for a second infection fro the same pathogen

3

Who are more vulnerable to infection

ill, young and old

4

What are the 2 responses involving a lymphocyte

1) cell-mediated responses involving T lymphocytes
2) humoral responses involving B lymphocytes

5

What must the lymphocytes do in order to defend the body from invasion

recognise self cells and non-self cells

6

What are self cells

the boyds own cells and molecules

7

What are non-self cells

foreign cells and molecules

8

Why are proteins all different to each other

they each have a highly specific tertiary structure that varies for each protein

9

What does the body identify (4 points)

1) pathogens - e.g. HIV
2) non-self material - e.g. cells from other beings of the same species
3) toxins - including those produced by certain pathogens
4) abnormal body cells - e.g. cancer cells

10

What is the issue with transplants

the body recognises them as non-self and tries to destroy them

11

How can you limit this issue with transplants

donor tissues are matched as closely as possible to those of the recipient, and immunosuppressant drugs

12

What is the issue with immunosuppressant drugs

they are not protected from pathogens so can become ill

13

what are the 2 types of defence mechagnism

1) non-specific
2) specific

14

What is a non-specific defence mechanism

response is immediate and the same for all pathogens

15

What is a specific defence mechanism

response is slower and specific to each pathogen

16

What are the 2 types of non-specific defences

1) physical barrier - e.g. skin
2) phagocytosis

17

What are the 2 types of specific defences

1) cell-mediated response (T lymphocytes)
2) humoral response (B lymphocytes)

18

What do foreign antigens trigger

immune respons

19

What are antigens

molecules (usually proteins) that can generate an immune respone when detected by the body

20

Where are antigens usually found

on the surface of cells

21

What are antigens used by

the immune system

22

What are antigens used to indentify (4 points)

1) pathogens
2) abnormal body cells
3) toxins
4) cells from other individuals from the same species

23

What is a pathogen

disease causing microbe

24

What are examples of abnormal body cells

cancerous cells, pathogen-infected cells

25

What are abnormal body cells

cells that have abnormal antigens on their surface

26

What is a phagocyte

type of white blood cell that carries out phagocytosis

27

What is phagocytosis

engulfment of pathods

28

Where are phagocytes found

in the blood and tissues

29

What are the 2 main types of white blood cell

lymphocyte and phagocyte

30

How do lymphocytes recognise cells belonging to the body (6 points)

1) lymphocytes continuously colliding with other cells in the fetus
2) infection in the fetus is rare, so only collide with self cells
3) some lymphocytes have receptors that fit those of the own bodys cell
4) these either die or are suppressed
5) only the ones that fit & respons to non-self material are left
6) any lymphocytes that show an immune response to self-cells undergo apoptosis, leaving only those that respond to non-self