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Flashcards in immune system Deck (56):
1

what is innate (non-specific) immune system?

-first line of defence
-responses are rapid but limited
use toll-like receptors

2

does the innate immune system involve the production of antibodies?

no

3

what cells does the innate immune response include?

-neutrophils
-macrophages
-basophiles
-natural killer cells

4

what is the adaptive or specific immune system?

-specifically targets foreign material to which body has already been exposed
-takes time to prepare for attack
-involves antibodies
-formation of memory cells

5

what is the response of the adaptive immune system mediated by?

-response is mediated by B and T lymphocytes

6

what cells are in the adaptive immune system?

T cells
B cells
plasma cells

7

what are the chemical/internal innate barriers?

-neutrophils
-eosinophils
-basophils
-monocytes
-lymphocytes

8

what are neutrophils

highly mobile phagocytes that engulf and destroy unwanted material

9

what are eosinophils

-secrete chemicals that fight parasites
-involved in allergic reactions

10

what are basophils

-release histamine and heparin
-involved in allergic reactions

11

what are monocytes

-transformed into macrophages

12

what are lymphocytes

1) B cells
-transformed into plasma cells that secrete antibodies
2) T cells
-responsible for cell-mediated immunity
-directly destroy and invade mutant cells

13

what is the complement system?

its a system that compliments the actions of antibodies to kill foreign cells by forming membrane attack complexes (MAC)

14

how does the compliment system work/ consist of?

consist of plasma proteins, when activated, the donut shaped protein complex embeds itself in the surface membrane of nearby microorganisms , creating a large channel through the membrane- the hole punching technique makes the membrane makes the membrane leaky, resulting in the victim cell swelling and bursting.

15

what does interferon act as?

a whistle blower

16

how does interferon work?

When a virus invades a cell, in response to being exposed to nucleic acid, the cell secretes interferon. Once released into the EFC, interferon binds with receptors on the plasma membrane of a healthy neighboring cell as a signal that they need to prepare for a viral attack Interferon is a whistle blower.

17

what does interferon trigger?

Interferon triggers the production of virus-blocking enzymes. Shen interferon binds with other cells, they synthesis enzymes that can break down RNA and inhibit protein synthesis

18

what other actions can interferon do?

-enhances macrophage activity and antibody production
-exerts anticancer (NK cells) and T cells
-slows cell division
enhances action of NK cells,

19

what is inflammation?

-non specific response to tissue injury with the help of a macrophages and neutrophils

20

are NK cells specific or non specific?

non- specific
-they lyse and destroy virally infection host cells and cancerous cells

21

what is the sequence of inflammation

-defense of resident tissue macrophages
-localized vasodilation
-increased capillary permeability
-localized oedema
-walling off the inflamed area
-emigration of leukocytes
leukocyte proliferation
-marking of destruction of bacteria
-mediation of inflammatory response by phagocyte-secreting chemicals
-tissue healing and repair

22

what occurs In localized vasodilation

- bacteria invasion at injury
-release of histamine
-enhances dilation of blood vessles, so more blood flow can go to injured site
-brings more leucocytes and plasma proteins

23

what is localized oedema?

-the accumulation of plasma proteins in internstial fluid
-moves fluid out of capillary and accumulate in injured area
-causes swelling
-pain from inflammation is causes by distention of swollen tissue and prostaglandins

24

what occurs in the walling off the inflamed area?

-leaked plasma proteins also brings thromboplastin- thrombin
-this converts fibrinogen into fibrin
-forms a clot around the bacterial invader and damaged tissue
walling off prevents spread of invaders

25

what are the 3 ways leukocytes emigrate to invaded tissue?

-margination
-diapedesis
-chemotaxis

26

what do chemotaxis (secreted by macrophages) do?

-attract neutrophils and monocytes which squeeze out between cells of the blood vessles (diapedesis) and migrate of the infection site

27

what happens in the destruction of bacteria phase?

macrophages and neutrophils release hydrolytic enzymes (lysosomes) that break down bacteria and trap it, the trapped portion forms pus.

28

what does interleukin (IL-1) do?

increases proliferation and differentiation of B and T cells for antibody production and cell-mediated immunity

29

what are the two subgroups of specific immunity?

1) antibody-mediated or humoral immunity
2) cell-mediated immunity

30

what does antibody-mediated/ humoral immunity involve?

-production of B lymphocytes derived from plasma cells

31

what do B cells do

B cells: recognize free existing foreign invaders, such as bacteria and their toxins, a few viruses, secrete antibodies specific for invaders

32

what does cell-mediated immunity involve?

involves production of T cells

33

what do T cells do?

-directly attack unwanted cells
-specialize in recognition and destroying body cells gone awry, including virus- infected cells and cancer cells.

34

what is an antigen?

-a surface protein present on the microbes and tags a microbe as a foreigner

35

structure of antibody?

-Y shaped
- made up of four interlinked polypeptide chains
-has two, long heavy chains, and two short light chains

36

where Is the antigen binding site?

fab, of the Y region
-determines what the antigen can bind to

37

what does the tail portion of the antibody do and what is it called?

fc
-region determines the functional; properties of the antibody

38

what does IgM do?

serves as a B cell surface receptor for antigen attachment and secreted in the early stages of plasma cell response

39

what does IgG do?

most abundant in blood
-only produced when body is exposed to the same antigen

40

what is IgA found?

found in the secretion of the digestive, respiratory, and milk and tears

41

what does IgE do?

-helps protect against parasitic worms
-involved in common allergic responses

42

where is IgD present?

Is present on the surface of many B cells

43

what are the two possibilities that B cells do when binding to a presented antigen?

1) differentiate into active plasma cells
2) become dormant

44

what happens after B cells differentiate into plasma cells?

-they produce specific antibodies to neutralize specific antigen

45

what do plasma cells do?

-produce and secrete IgG antibodies
-marks antigen for destruction

46

what is the other thing that B cells can become?

memory cells (dormant)

47

what is active immunity?

-self generated
-results from exposure to antigen

48

what is passive immunity?

-borrowed immunity
-from mother to fetus

49

T cells

they don't secrete antibodies, the directly bind and destroy target cells
-carry out cell mediated immunity

50

what are the two types of T cells?

1) CD8 cells
2) CD4 cells

51

what are CD8 cells?

-cytotoxic or killer T cells
-destroy host cells of anything foreign

52

what do CD4 cells do?

secrete chemicals that amplify the activity of other immune cells

53

what are the three methods of antigen neutralization?

-agglutination
-precipitation
-neutralization

54

what is agglutination

when foreign cells or mis-matched transfused RBS bind together and clumps

55

what is precipitation

when antigen-antibody complexes involves toxins that become large and separate out from solution

56

what is neutralization?

antibodies can physically hinder some antigens from exerting their effects