11. immunity

Question 1

lymph

Answer 1

fluid = water plus solutes form two sources, plasma and cells

Question 2

Lymphatic vessels

Answer 2

carry lymph away from tissues, contain half valves that ensure one-way flow

Question 3

Lymphatic capillaries

Answer 3

join to form lymphatic vessels, very permeable

Question 4

Lymphatic tissue

Answer 4

diffuse lymphatic tissue

Question 5

Lymphatic nodules

Answer 5

dense aggregations

Question 6

Lymph nodes

Answer 6

distributed along vessels and filter lymph, contain macrophages and lymphocytes and if
Cancer cells often trapped in lymph nodes therefore take them out aswell

Question 7

Lymphatic ducts:

Answer 7

drain tissues of body and move lymph into major veins

Question 8

Tonsils

Answer 8

large groups of lymphatic tissues
Provide protection against bacteria
Palatine (tonsils), pharyngeal (adenoids), lingual

Question 9

Spleen

Answer 9

monitors blood and detects and responded to foreign antigens, destroys defective red blood cells, regulates blood volume

Question 10

Thymus

Answer 10

site of maturation of T cells, many T cells produced here

Question 11

functions of the lymphatic system.

Answer 11

Fluid balance: excess interstitial fluid enters lymphatic capillaries and becomes lymph
Fat absorption: absorption of fat and other substances from digestive tract
Defence: fights infection

Question 12

different types of innate immunity

Answer 12

1. white blood cells
2. inflammation
3. fever
4. chemical mediators
5. physical barriers

Question 13

what is innate immunity

Answer 13

Non-specific
- each time the body is exposed the response is the same, the body doesn’t remember if you have had it or not

Question 14

1. white blood cells

Answer 14

White blood cells: ingest foreign particles (phagocytosis)
produce chemicals to attract other immune cells to area
Produced in bone marrow and lymphatic tissue
Released into blood and transported around the body

Question 15

types of white blood cells

Answer 15

Neutrophils: first cell to arrive, phagocytosis
Macrophages: more effective phagocyte
Basophils: produce histmine
Natural killer cells: can cause lysis of virus infected cells

Question 16

physical barriers

Answer 16

prevent entry or remove microbes
- skin, mucous membranes, tears, saliva

Question 17

3. Inflammation:

Answer 17

local tissue response to damage
aims to rid the body of debris/ invader and prevent further pathogen entry
4 features
Redness: increased blood flow to region
Heat: increased blood flow to region
Swelling: capillaries become leaky, fluid leaves capillaries into surround tissue
Pain: increased fluid stimulates pain receptors

Question 18

4. Chemical mediators:

Answer 18

promote phagocytosis (help white blood cells get rid of bacteria) and inflammation
\ histamine: cause vasodilation, attract white blood cells
Cytokines: secreted by one cell and stimulates neighbouring cell to respond
Complement: stimulates lysis of invading pathogen cells
Interferons: anti-viral activity

Question 19

fever

Answer 19

Fever: generalised response to tissue damage and infection
increase some antimicrobial substances
Decrease microbial growth
Increase body reactions that help tissue repair

Question 20

what is adaptive immunity

Answer 20

Specificity - ability to recognise a particular substance
Memory - ability to remember previous encounters with specific substance and respond rapidly
Acquired during a lifetime due to exposure

Question 21

types of adaptive immunity

Answer 21

Cell mediated immunity - T cells: specificity
Antibody mediated immunity - B cells: memory

Question 22

Cell mediated immunity - T cells: specificity

Answer 22

Helper T cells and cytotoxic T cells
Cytotoxic T cell attaches to the target cell receptor detecting if there is any virus on the target cell
Helper T cells help to reproduce the cytotoxic T cells to enable more cells to recognise the virus
Cytotoxic T cells release cytokines to produce inflammation and initiate phagocytosis
The cytotoxic T cells kill any target cells that they come into contact with that have the virus

Question 23

Antibody mediated immunity - B cells: memory

Answer 23

Phagocytosis of pathogen to express it on the cell surface
Helper T cell confirms if it is a virus or not
Interleukins are released to make the B cell divide
The B cell creates antibodies

Question 24

affects of antibodies

Answer 24

inactivate the antigen by binding to it
Bind antigens together, 3 antibodies inhibit 4 antigens
Facilitate phagocytosis: antibody binds to antigen and then to a macrophage which engulfs them both

Question 25

primary vs secondary immune response

Answer 25

Primary fewer antibodies Longer response time Vaccinations act as a primary response Secondary shorter response time and stronger response More antibodies recognising the pathogen Booster acts as secondary response

Question 26

antigen

Answer 26

foreign proteins in the body

Question 27

active immunity

Answer 27

provided by own individual immune system natural: antigens introduced through natural exposure Artificial: antigens introduced through vaccines

Question 28

passive immunity

Answer 28

transferred from another person or animal natural : antibodies transferred from mother to child in breast milk Artificial: antibodies produced from a person are injected into another person

Question 29

chyle

Answer 29

lymph with a lot of fat

Question 30

pathogen

Answer 30

foreign agent eg bacteria, pathogens introduce antigens into the body

Question 31

Immunity

Answer 31

ability to resist damage from foreign substances

Question 32

HIV

Answer 32

Destruction of helper T cells which impairs antibody mediated immunity body is vulnerable and ordinary infections can be lethal

Question 33

Enlarged lymph nodes

Answer 33

Bacteria in the tissues can enter the circulatory system through the permeable lymphatic capillaries of the lymphatic system. Bacteria will travel through the vessels and along the way become trapped in lymph nodes, particularly around the neck because of their closeness to the throat (pharynx) and nearby tonsils. Immune cells (lymphocytes and phagocytic cells) in lymph nodes will recognise the antigen and begin an immune response in order to remove the threat. These immune cells differentiate in the lymph nodes and multiply, which lead to the nodes become bigger.

Question 34

Achy body

Answer 34

* This symptom can be a consequence of toxins (poisonous waste products) released into the body from the bacteria. This can cause an all over achy body/muscle. * Aching can also be due to dehydration.

Question 35

lymphocytes

Answer 35

white blood cells from bone marrow

Question 36

macrophages

Answer 36

phagocytic cell important in inflammation and repair