topic 3.1

Question 1

what are the two parts of the immune system?

Answer 1

innate immunity and adaptive immunity

Question 2

a foreign substance that simulates an immune response and generates antibody production

Answer 2

antigen

Question 3

a specific protein produced in humoral response to bind with an antigen

Answer 3

antibody

Question 4

a gland located in superior mediastinum, it is the site of maturations of T lymphocytes

Answer 4

thymus

Question 5

contain many lmyphocytes, they filter body fluids, remove foreign matter and generate immune responses

Answer 5

lymph nodes

Question 6

disorders resulting from an overactive immune system that fails to recognise ‘self’

Answer 6

autoimmune disease

Question 7

specialised lymphocytes produced and matured in bone marrow, they are precursor to plasma and memory cells

Answer 7

B lymphocytes

Question 8

specialised lymphocytes produced by the bone marrow and matured in the thymus, which is responsible for cell-mediated immunity

Answer 8

T lymphocytes

Question 9

white blood cells for phagocytosis, an innate defence, they are active in inflammation

Answer 9

neutrophils

Question 10

white blood cells, they bind IgE and also release histamines

Answer 10

basophils

Question 11

white blood cells, they participate in allergic responses and defence against parasites

Answer 11

eosinophils

Question 12

white blood cells, they migrate from the blood into tissues to become macrophages

Answer 12

monocytes

Question 13

phagocytes, they process and present antigens to lymphocytes for the immune response

Answer 13

macrophages

Question 14

found within connective tissue, they release chemical mediators such as histamines

Answer 14

mast cells

Question 15

develop from B lymphocytes to produce and secrete antibodies

Answer 15

plasma cells

Question 16

they destroy antigens, cancer cells and virus cells

Answer 16

cytotoxic T cells

Question 17

what is the purpose of cytotoxic T cells?

Answer 17

to destroy antigens, cancer cells and virus cells

Question 18

remembers antigens and quickly stimulates an immnue response

Answer 18

memory T cells

Question 19

activates B and T cells, also controls or limits the specific immune response

Answer 19

helper T cells

Question 20

part of the innate immune system, they destroy foreign cells, virus infected cells and cancer cells

Answer 20

natural killer cells

Question 21

a generic term for any cell responsible for engulfing pathogens, waste material and foreign bodies

Answer 21

phagocytes

Question 22

condition of being resistant to infection by a specific pathogen

Answer 22

immunity

Question 23

a state where the immune system is unable to fight infection

Answer 23

immunodeficiency

Question 24

agents used to reduce an immune response

Answer 24

immunosuppressants

Question 25

a type of acquired immunity in which antibodies play the dominant role

Answer 25

humoral immunity

Question 26

a type of acquired immunity in which T cells play the dominant role

Answer 26

cell-mediated injury

Question 27

define innate immunity

Answer 27

includes all anatomical structures and processes that: - prevent entry of damaging substances - response non-specifically to damaging substance that has entered body

Question 28

what is the body’s first line of defence?

Answer 28

the skin, mucous membranes, stomach acid, etc.

Question 29

how does temperature provide a barrier to pathogens?

Answer 29

by inducing a fever, as this inhibits the growth of some pathogens and boost immune function

Question 30

what are interferons (INF)?

Answer 30

an antiviral substance, helps prevent spread of virus

Question 31

what is complement?

Answer 31

a cascade of plasma proteins that is effective against bacteria

Question 32

how does complement work?

Answer 32

- increases inflammation by activating basophils, mast cells + the attraction of neutrophils and macrophages - eliminates immune complexes - induces cytolysis by forming MAC transmembrane protein

Question 33

what is adaptive immunity?

Answer 33

is capable of recognising + selectively eliminating specific dangerous substances

Question 34

what are the 4 main characteristics of adaptive immunity?

Answer 34

1. antigenic specificity 2. diversity 3. immunologic memory 4. self/non-self recognition

Question 35

what are the 3 types of antigens?

Answer 35

1. foreign (come from pathogens) 2. tumour (proteins on tumour cells) 3. self-antigens (antigens on our own cells)

Question 36

what are the 5 classes of antibodies?

Answer 36

1. IgD 2. IgE 3. IgM 4. IgA 5. IgG

Question 37

what percentage are the 5 classes of antiodies found in the body?

Answer 37

1. IgD - 1 2. IgE - <1 3. IgM - 6 4. IgA - 13 5. IgG - 70-80

Question 38

where are the 5 classes of antibodies located?

Answer 38

1. IgD - bound to surface of B cells 2. IgE - bound to mast cells + basophils 3. IgM - involved in early humoral immunity 4. IgA- mucous membrane secretions 5. IgG - main antibody in humoral immunity

Question 39

what are the 3 main ways that antibodies work to neutralise/remove damaging substances?

Answer 39

1. opsonisation - antibodies coat pathogen, enhance phagocytosis 2. complement fixation - antibodies coat pathogen, sigal 4 blood complement system to destroy pathogen 3. neutralisation - antibodies coat pathogen, prevents it from replicating + interacting

Question 40

what does the B cell response most effectively fight against?

Answer 40

pathogens that are extracellular, such as bacteria

Question 41

explain process of humoral response (B cell response)

Answer 41

1. antigen enters body, B cells that recognise antigen get cloned 2. these B cells need activation by helper T cells 3. activated B cells divide = large population of specific B cell 4. most will differentiate into plasma cells, small amount will -> memory B cells to rpovide long-term memory against antigen

Question 42

what are Th cells?

Answer 42

- helper T cells - they express surface protein called CD4 so they also called CD4 T cells

Question 43

what are Tc cells?

Answer 43

- cytotoxic T cells - they express protein called CD8, so they also referred to as CD8 Tc cells

Question 44

what is the main role of CD8/Tc cells?

Answer 44

to destroy virus or tumour infected cells

Question 45

what is the main role of CD4/Th cells?

Answer 45

to activate B cells or Tc cells

Question 46

what are antigen-presenting cells (APC)?

Answer 46

phagocytes that display phagocytosed pathogens on their membrane

Question 47

what do antigen presenting cells (APCs) do?

Answer 47

- once displaying the antigen, they move to local lymph node to present antigen to T cells - this activates the T cells in local lymph node and can cause swelling and tenderness of this node