immunity Flashcards

Question

external non specific defences: first line of defence: mucus

Answer 1

mucuos membranes line body’s cavities that open to exterior, they secrete mucus which trap particles therefore inhibits entry of microorganisms to organs

Answer 2

found in nasal cavities, in the nose the hairs and a layer of mucus trap 90% of particles inhaled when breathing

Answer 3

tiny hair like projections from cells that are capable of a beating motion, mucuous membrane that line nasal cavity, trachea and other air passages have cilia, beating movement of cilia moves the mucus containing trapped particles and microorganisms toward throat where they can be coughed up or swallowed

Answer 4

stomach juices are strongly acidic and this kills many bacteria taken in with food or contained in mucus swallowed from nose/windpipe, vagina also has acidic secretions that reduce growth or microorganisms and sweat is slightly acidic

Answer 5

enzymes that kill bacteria, eyes are protected by flushing action of tears, which contain this enzyme and is also found in saliva, sweat, secretion of nose, tissue fluid

Answer 6

ear wax, protects the outer ear against infection by some bacteria, slightly acidic, contains lysosomes

Answer 7

flushing action of body helps keep some areas relatively free of pathogens, urine flowing through urethra has cleansing action which prevents bacteria, growth and helps stop bacteria texting bladder or kidneys, tears, sweat, saliva are also flushing actions

Answer 8

automatic involuntary response to a stimuli, helps protect body from injury e,g blinking or vomiting

Answer 9

- stimulus is irritation of walls of nasal cavity, may be caused by noxious fumes or dust particles likely to be carrying microorganisms, forceful expulsion of air from lungs, carries mucus, foreign particles and irritating gases out through nose/ mouth

Answer 10

stimulus = irritation in lower respiratory tract, air is forced from lungs to try and remove irritant, air drive mucus and foreign matter up trachea toward throat/mouth

Answer 11

psychological stimuli or excessive stretching of stomach and bacterial toxins can induce vomiting, contraction of muscles of abdomen/diaphragm (not stomach) expels stomach contents

Answer 12

irritation of small or large intestines by bacteria, viruses or protozoans, causes increased contraction of muscles along wall of intestines so irritant is removed as quickly as possible, material does not stay in large intestine long enough to be absorbed so faeces are watery

Answer 13

specialised white blood cells

Answer 14

engulf and digest microorganisms/cell debris

Answer 15

if tissue becomes inflamed monocytes leave blood stream and enter tissue, they differentiate into macrophages (large phagocytic cells) these move through tissue looking for and destroying pathogens, others are in fixed places and only deal with pathogens that come to them - macrophages are important in removing microbes and dying cells through phagocytosis

Answer 16

First cell to move to tissue to destroy pathogen by phagocytosis during an infection, short lifespan and dies after a few days, dead cells make up large portion of pus that forms after infection

Answer 17

characterised by projections from cytoplasm, have ability to use info about ingested particles to assist with specific immunity

Answer 18

response to any damage to tissue, reduces the spread of pathogen to destroy them and prevent entry of additional pathogens, remove damaged tissue and cell debris, begin repair of damaged tissue

Answer 19

1. mechanical damage/local chemical changes: cause mast cells to become activated by complement proteins, triggers release of histamine and heparin into tissue fluid 2. Histamine increases blood flow and causes capillaries to become more permeable so more fluid moves through capillary wall into tissue which causes heat and redness and causes swelling 3. Heparin: prevents clotting in immediate area of injury, clot of fluid forms around damaged area which slows spread of pathogen into healthy tissue 4. complement system proteins & some chemicals released by mast cells attract phagocytes which actively consume microorganisms and debris 5. abnormal conditions in tissue stimulate pain receptors so person feels pain 6. phagocytes filled with bacteria, debris and dead cells begin to die and this forms yellow liquid pus 7. new cells are produced by mitosis and repair of damaged cells takes place

Answer 20

change in body temperature due to resetting of body’s thermostat controlled by the hypothalamus to a higher level, due to pyrogen: released by white blood cells during inflammatory response, temperature is still regulated just at an abnormally high level

Answer 21

person feels cold, and responds by shivering which increases heat production and vasoconstriction which prevents heat loss and increase body temp significantly

Answer 22

body’s thermostat returns to normal and the person feels hot and appears flushed, vasodilation in skin and profuse sweating occurs to cool body back to normal temperature

Answer 23

collect fluid that escapes from blood capillaries and return it to circulatory system, important part of body’s internal defence against pathogens

Answer 24

contains masses of lymphoid tissue whos cells are crisscrossed by network of fibres, lymph entering lymph nodes contains cell debris, foreign particles and microorganisms that have gotten past body’s external defences, larger particles are trapped in network of fibres as lymph flows through spaces in nodes, macrophages ingest and destroy these particles by phagocytosis

Answer 25

composed of cells and proteins that protect against a foreign organism, range of chemicals as well as cancerous and other abnormal cells

Answer 26

helps deal with invasion and restore internal environment to normal condition

Answer 27

lymphocytes both produced in bone marrow and end up in lymphoid tissue however they mature differently, half cells produced in bone marrow go to thymus and mature into T-cells, other cells mature in bone marrow to become B-cells then become part of lymphoid tissue

Answer 28

antibody mediated immunity, involved production of antibodies by B-cells which circulate around body and attack invading pathogens

Answer 29

due to T-cells and involves formation of special lymphocytes that destroy invading pathogens

Answer 30

any substance that is capable of causing a specific immune response

Answer 31

large molecules produced in a persons own body and do not cause immune response

Answer 32

y shaped specialised proteins produced by plasma cells in response to non self antigens, belong to group of proteins (immunoglobulin : lg), produced in response to antigen and can combine with a particular shape, antibody has complementary shape which allows them to fit together (lock and key)

Answer 33

provides resistance to viruses, bacteria, bacterial toxins, before microorganisms enter the body’s cell, when antigen activated the B-cells enlarge and divide into clones which become plasma cells which secrete specific antibodies capable of attaching to antigen, antibodies circulate in blood and lymph/extracellular fluid to reach site of invasion of microorganism, remaining B-cells become memory cells and spread to all body tissues which allow the response to occur more rapidly if antigen enters body again

Answer 34

immune response to first exposure to an antigen, body reacts slowly and take several days to build large amounts of antibodies and takes time for B-cells to multiply and differentiate into plasma cells and secrete antibodies

Answer 35

subsequent exposure to same antigen, response is much faster bc of memory cells and plasma cells are able to form quickly with antigen body levels in blood plasma rising rapidly and lasts longer than primary response

Answer 36

may: - inactivate foreign enzyme/toxins, combining with them or inhibiting the antigens reaction with other cells - binds to surface of viruses and prevents up them from entering cell - coats bacteria so they are easily consumed by phagocytes - dissolve organisms - cause particles to clump together (agglutination) - react with soluble substances to make them insoluble, more easily consumed by phagocytes

Answer 37

provides resistance to intracellular phase of bacterial/viral infections, these invade and replicate inside hosts own cells, more difficult to overcome, involved in rejection of transplant of foreign tissue and fighting cancer cells, T-lymphocytes are responsible

Answer 38

- foreign antigen enters body and particular type of T-cell programmed for that antigen becomes activated (only occurs after B-cell enters foreign antigen and travels to lymph node and presents it to T-cells - the sensitised T-cells enlarge and divide forming clones, some cells of clone stay in lymphoid tissue as memory cells and others develop into - killer T-cells: migrate to site of infection and deal with invading antigen, attach to invading cell and secrete substance that destroys antigen then searches for more antigens - helper T cells: secrete number of substances that cause lymphocytes at infection to become sensitised and increases intensity of reaction, attract macrophages to place of infection so they can destroy antigen by phagocytosis, intensify phagocytic activity of macrophages - suppressor T cells: act when immune activity becomes excessive or infection has been dealt with, releases substances that inhibit T-cells and B-cells activity,slowing down immune response

Answer 39

resistance to infection by invading microorganisms, presence of memory cells allows body to respond quickly enough to deal with any invasion by pathogenic microorganisms before symptoms of disease occur

Answer 40

occurs without any human interventions

Answer 41

results from giving people antibody

Answer 42

when a person receives antibodies produced by someone else and individuals body plays no part in production of antibodies, can occur naturally e.g antibodies from mother pass across placenta to foetus, occur artificially when one is injected with antibodies to combat a particular infection when one is injected with antibodies o combat a particular infection, this method is only short lived and only lasts until antibodies are broken down and excreted

Answer 43

results when body is exposed to foreign antigen and manufactures antibodies in response to the antigen, lasts longer than passive immunity due to presence of memory cells

Answer 44

artificial introduction of antigens of pathogenic organisms so ability to produce those appropriate antibodies is aquifer (memory cells formed) without person having to suffer diseases

Answer 45

programming immune system so body can respond rapidly to infecting microorganisms

Answer 46

live microorganisms that has been reduced in force or strength, microorganisms with reduced ability to produce disease symptoms, manufactures antibodies against antigen

Answer 47

contain dead microorganisms, shorter lasting than live attenuated microorganisms but follows same idea

Answer 48

toxins produced by bacteria can be inactivated so when injected they do not make person ill but person develops antibodies

Answer 49

injection, orally, in lumps of sugar

Answer 50

group of immunity that occurs when such a high proportion of people in a population are immunised, those who are not immune are protected as it reduces chances of transmission

Answer 51

drugs used to fight infections of microorganisms especially bacteria

Answer 52

kill bacteria by changing structure of cell wall/membrane or by disrupting action of enzymes

Answer 53

stop bacteria from reproducing, usually by disrupting protein synthesis

Answer 54

effective only against specific types of bacteria

Answer 55

resistance to some strains of bacteria to most available antibiotic, increases by overuse

Answer 56

resistance of some strains of bacteria to all antibiotics

immunity Flashcards

(80 cards)