communicable diseases, disease prevention and the immune system Flashcards

(187 cards)

1
Q

pathogen definition

A

an infectious micro-organisms that causes disease

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2
Q

4 major types of pathogen that cause disease in animals and plants

A

bacteria (prokaryotic)
viruses (non-living parasites)
protoctists (animal-like or plant-link eukaryotes)
fungi (eukaryotic)

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3
Q

communicable disease definition

A

a disease that can be transmitted from one organism to another

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4
Q

infectious definition

A

infectious diseases are those caused by micro-organisms (mostly bacteria, viruses, fungi, protozoa, parasites) that spread by direct or indirect means form one individual to another

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5
Q

vector-borne disease definition

A

diseases spread by other animals. for diseases of humans and domestic animals, the most important vectors are flies (mosquitoes, midges), fleas, lice and ticks. aphids are important vectors of disease in plants
water is also a vector because it carries parasites

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6
Q

why have infectious diseases e.g. diphtheria, leprosy, scarlet fever largely died out?

A

due to vaccines, antibiotics, improvements to sanitation ad changes in land use

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7
Q

which aspects of modern life have given rise to disease emergence

A

increased tourism to exotic locations
increased trade of animals and animal products
intensification of farming
cutting down of rainforests
climate change causing rise in global temps, so increasing distribution of vectors and their capacity to transmit pathogens. can also turn non-vectors into vectors
climate change may impact agriculture so increase reliance on bush meat

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8
Q

pandemic definition

A

an epidemic of a disease across huge areas of the world

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9
Q

how did the H1N1 influenza virus in 2009 come about?

A

arose from genetic changes in existing influenza viruses

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10
Q

how did the AIDS pandemic come about in the 1980s?

A

it is caused by HIV that is spread through exchange of bodily fluids e.g. via blood transfusion, needle-sharing by drug users, more liberal sexual practices.

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11
Q

examples of diseases?

A

tuberculosis (TB)
bacterial meningitis
ring rot
HIV/AIDS
influenza
TMV
black sigatoka
blight
ringworm
athletes foot
malaria

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12
Q

characteristics/symptoms of tuberculosis (TB)
animal or plant disease?

A

disease that affects many parts of the body, particularly the respiratory system. tubercles form in the lungs
animal

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13
Q

what kind of organism causes tuberculosis?

A

bacteria

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14
Q

tuberculosis method of transmission?

A

respiratory droplets

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15
Q

bacterial meningitis characteristics/symptoms?
animal or plant disease?

A

infection/inflammation of the meninges in the brain. causes major damage to the brain and nerves; lethal if not treated quickly
animal

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16
Q

what kind of organism causes bacterial meningitis?

A

bacteria

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17
Q

bacterial meningitis method of transmission?

A

respiratory droplets

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18
Q

ring rot characteristics/symptoms?
animal or plant disease?

A

ring of decay in vascular tissue of potato tuber or tomato, accompanied by leaf wilting
plant

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19
Q

what kind of organism causes ring rot?

A

bacteria

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20
Q

ring rot method of transmission?

A

infected farming equipment

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21
Q

HIV/AIDS characteristics/symptoms?
animal or plant disease?

A

attacks T helper (CD4+) cells in the immune system and compromises immunity
sufferers often die of opportunistic infections (e.g. pneumonia)

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22
Q

what kind of organism causes HIV/AIDS?

A

virus

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23
Q

HIV/AIDS method of transmission?

A

needle sharing
unprotected sex
blood transfusion

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24
Q

influenza characteristics/symptoms?
animal or plant disease?

A

attacks respiratory system and causes muscle pains and headaches
animal

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25
what kind of organism causes influenza?
virus
26
method of transmission of influenza?
respiratory droplets
27
TMV characteristics/symptoms? animal or plant disease?
causes mottling and discolouration of leaves plant
28
disease-causing organism of TMV?
virus
29
method of transmission of TMV?
infected farming equipment
30
black Sigatoka characteristics and symptoms? plant or animal disease?
causes leaf spots on banana plants reducing yield plant
31
what kind of organism causes black Sigatoka?
fungi
32
method of transmission of black Sigatoka?
spores
33
blight characteristics/symptoms? plant or animal disease?
affects leaves in potatoes and tomatoes, affects potato tubers plant
34
what kind of organism causes blight?
protoctist
35
method of transmission of blight?
aphids (VECTOR)
36
ringworm (cattle) characteristics/symptoms? plant or animal disease?
growth of fungus on skin and spore case erupting through to cause a rash animal
37
type of organism that causes ringworm?
fungi
38
method of transmission of ringworm?
spore/ direct contact
39
athletes foot characteristic/symptoms? plant or animal disease?
growth under skin of feet, particularly between toes animal
40
type of organism that causes athletes foot?
fungi
41
athletes foot method of transmission?
direct contact fomites
42
malaria characteristic/symptoms? plant or animal disease?
mosquito acts as vector and injects parasite into bloodstream causes headaches, fevers and potentially comas and death animal
43
what type of organism that causes malaria?
protoctist
44
malaria method of transmission?
anophales mosquito (acts as a vector)
45
what is a fomite?
an inanimate object that holds a pathogen
46
antibiotic definition
a drug that slows bacterial growth (bacteriostatic) or kills bacteria (bactericidal)
47
what was the first antibiotic? what was it derived from?
penicillin the fungus Penicillium
48
how does penicillin work?
by inhibiting cell wall synthesis
49
what are the 2 general categories of antibiotics?
broad-spectrum (act on a wide range of bacteria) narrow-spectrum (act on only a few)
50
examples of antibiotics?
pencillins, cephalosporins, vancomycin, cycloserine rifampicin chloramphenicol fluoroquinolones polymixins sulfonamides
51
how do penicillin, cephalosporins, vancomycin (last resort) and cycloserine act?
act to inhibit cell wall synthesis
52
how does rifampicin act?
acts to inhibit DNA transcription therefore stop mRNA synthesis so stop translation
53
example of fluoroquinolones?
ciprofloxacin
54
how do fluoroquinolone (e.g. ciprofloxacin) act?
act to inhibit DNA replication therefore prevent binary fission
55
how do polymixins act?
act to inhibit plasma membrane synthesis
56
how do sulfonamides act?
act to (competitively) inhibit the enzyme DHPS which promotes DNA replication
57
how is DNA organised in bacteria?
single circular chromosome (genes arranged in clusters (OPERONS)) plasmids (can contain resistance genes)
58
how has antibiotic resistance come about (brief)
there is an evolutionary race between scientists and bacteria incorrect (prescription when not required) and inappropriate use over many years has led to the development of antibiotic-resistant bacteria
59
how do bacteria become antibiotic-resistant?
if a random mutation during reproduction produces a bacterium that is not affected by the antibiotic, it is best-fitted to survive and reproduce, passing on the antibiotic-resistance mutation to its daughter cells
60
why does it not take long for an antibiotic-resistance gene to become common in a bacterial population?
due to the speed at which bacteria grow and divide
61
natural selection process in bacteria population
resistant bacteria present due to random mutation which creates new alleles antibiotics (selection pressure) applied susceptible bacteria are killed and resistant bacteria survive & reproduce & pass on the resistance allele to offspring over repeated exposure to antibiotics, the resistant population grows and the allele frequency for resistance increases
62
what are the reasons for the acceleration of development of antibiotic resistance?
in some countries (e.g. USA) farmers routinely add antibiotics to feed animals prophylactically (prevents animals losing condition due to infection) over-prescription of antibiotics patients not completing their course of antibiotics
63
do viruses usually act extracellularly or intracellularly?
intracellular: act inside cells
64
examples of viruses how transmitted
coronavirus, influenza, common cold all easily transmitted through respiratory droplets
65
step-by-step how is HIV able to self-replicate?
virus binds to a receptor on the plasma membrane of host cell virus injects its DNA/RNA into the cell (integrates DNA/RNA into host nucleus) host cell synthesises viral proteins proteins are assembled to form mature viruses viruses continue to be produced viruses are burst out of the host cell to infect other host cells.
66
integrase function in a virus
inserts the viral DNA into the host cell DNA
67
reverse transcriptase function in a virus
converts virus RNA into DNA
68
why does virus have RNA rather than DNA
acts as extra line of security harder for target to recognise
69
what kind of cells does HIV target?
T Helper Cells
70
difficulties encountered treating diseases like ebola, which is caused by a pathogen that has only recently evolved to infect humans
correctly identifying symptoms is difficult no reliable cures or treatments vaccine only licensed in 2019 viruses evolve quickly and form new variants
71
how is C.diff infection transmitted?
contracted by ingesting spores: usually picked up from contaminated surfaces esp. in hospitals and nursing homes spores pass through alimentary tract to the colon where they form colonies
72
what are broad-spectrum antibiotics? potential implications of use of broad-spectrum antibiotics?
they can treat and kill a wide range of bacteria potential implications: resistance can form. also these drugs can upset the delicate balance of bacteria in the colon. this means C.difficile can dominate (outcompete) gut bacteria & produce toxins which make a person seriously ill
73
clostridium enters cells by receptor-mediated endocytosis what does this mean?
it binds to a receptor on the plasma membrane of the cell which causes the cell to ingest the pathogen by endocytosis (PHAGOCYTOSIS)
74
what 2 antibiotics are used to treat C.diff? how do they work?
metronidazole- bacteria cannot produce nucleic acids so cannot form DNA vancomycin- prevents cell wall synthesis
75
how to prevent infection by C.diff?
isolate patients with suspected infection rigorous hand-washing and disinfecting procedures
76
methods of direct transmission in animals
contact entry through the skin ingestion
77
methods of indirect transmission in animals
fomites inhalation vectors
78
transmission of communicable pathogens by direct contact in animals: description examples
bodily fluids, kissing, contact with skin STIs, diarrhoeal diseases
79
transmission of communicable pathogens by entry through skin in animals: description examples
wounds, animal bites, needles HIV, hepatitis, rabies
80
transmission of communicable pathogens by ingestion in animals: description examples
contaminated food and drink diarrhoeal diseases
81
transmission of communicable pathogens by fomites in animals: description examples
(inanimate object that harbours pathogens) bedding, socks, cosmetics athletes foot, coldsore viruses
82
transmission of communicable pathogens by inhalation in animals: description examples
breathing in respiratory droplets colds, flu, TB
83
transmission of communicable pathogens by vectors in animals: description examples
pathogens are carried from one host to another e.g. animals, water malaria, bubonic plague, African sleeping sickness
84
plants mode of direct transmission of disease
direct contact
85
plants modes of indirect transmission of disease
soil contamination vectors
86
transmission of communicable pathogens by direct contact in plants: description example
between healthy plants & diseases plants incl. infected farming equipment e.g. TMV
87
transmission of communicable pathogens by soil contamination in plants: description examples
reproductive spores are left in the soil black Sigatoka, ring rot
88
transmission of communicable pathogens by vectors in plants: description example
wind, water, animals blight
89
factors affecting rate of transmission of communicable pathogens ANIMALS ONLY
immunocompromisation socioeconomic factors poor waste disposal culture (lifestyle, food, drink)
90
factors affecting rate of transmission of communicable pathogens PLANTS ONLY
susceptible crops
91
factors affecting rate of transmission of communicable pathogens ANIMALS AND PLANTS
damp/warm conditions climate change overcrowding poor nutrition (decreases resistance)
92
types of defence mechanisms to prevent infection in plants
passive (prevent entry) active (induced when pathogen detected)
93
the 2 types of passive defence mechanisms to prevent infection in plants
physical chemical
94
the 7 types of physical passive defence mechanisms to prevent infection in plants
cellulose cell wall lignin thickening of cell wall waxy cuticles bark stomatal closure callose tylose formation
95
why is cellulose cell wall important for plant defence?
acts as a physical barrier most contain a variety of chemical defences which can be activated when a pathogen is detected
96
why is lignin thickening of cell walls important for plant defence?
lignin ( a phenolic compound) is waterproof and almost completely indigestable
97
why is waxy cuticle important for plant defence?
prevents water collecting on cell surfaces since pathogens collect in water and need water to survive, the absence of water is a passive defence
98
why is stomatal closure important for plant defence?
stomata= entry points for pathogens stomatal aperture controlled by guard cells; when pathogenic organism detected, guard cells will close stomata in that part of the plant
99
why is bark important for plant defence?
most bark contains a variety of chemical defences which work against pathogenic organisms
100
why is callose important for plant defence?
callose= large polysaccharide deposited in sieve tubes at end of the growing season deposited around sieve plates & blocks the flow in sieve tube so can prevent pathogen spreading around the plant
101
why is tylose formation important for plant defence?
a tylose= a balloon-like swelling or projection that fills xylem vessel when a xylose is fully formed, it plugs the vessel so vessel cannot carry water blocking a xylem vessel prevents spread of pathogens through the heartwood tylose contains high conc. of chemicals e.g. terpenes, which are toxic to pathogens
102
chemical passive defence mechanisms in plants?
plant tissues contain a variety of chemicals which have anti-pathogenic properties e.g. terpenoids, phenols, alkaloids, hydrolytic enzymes some of these chemicals e.g. terpenes in tyloses & tannins in bark are present before infection. however, bc production of chemicals requires lots of energy many chemicals are not produced until plant detects an infection
103
forms of active defence mechanisms in plants?
increase in the production of chemicals cell walls become thickened and strengthened w/ additional cellulose deposition of callose between plant cell wall & plasma membrane nr invading pathogen (impedes cellular penetration @ site of infection, strengthens cell wall, blocks plasmodesma) oxidative bursts that produce highly reactive oxygen molecules capable of damaging the cells of invading organisms necrosis (deliberate cell death) whereby a few cells are sacrificed to save the whole plant. pathogen access to water and nutrients and its spread around the plant are limited. process facilitated by intracellular enzymes activated by injury. canker: sunken necrotic lesions in woody tissues. causes of death of cambium tissue in bark
104
there is an increase in production of certain chemicals in active response to an invading pathogen. list 5 of these
terpenoids phenols alkaloids defensins hydrolytic enzymes
105
outline terpenoids' role in active response in plants
range of essential oils, have antibacterial & anti fungal properties. may also create scent e.g. menthols, menthes produced by mint plants
106
outline phenols' role in active response in plants
have antibiotic & anti fungal properties. tannins in bark inhibit attack by insects. these compounds bind to salivary proteins & digestive enzymes e.g. trypsin, chymotrypsin, deactivating the enzymes. insects that ingest high amounts of tanning don't grow & will eventually die helps prevent transmission of pathogens
107
outline alkaloids' role in active response in plants
nitrogen-containing compounds e.g. caffeine, nicotine, cocaine, morphine, solanine give bitter taste to inhibit herbivores feeding act on metabolic reactions via inhibiting/ activating enzyme action some inhibit protein synthesis if plant can reduce grazing by larger animals, it will suffer less damage that can allow pathogens to enter plant
108
outline defensins' role in active response in plants
cysteine-rich proteins with broad anti-microbial activity appear to act on molecules in plasma membrane of pathogens, possibly inhibiting action of ion transport channels
109
outline hydrolytic enzymes' role in active response in plants
found in spaces between cells, include chitinases (break down chitin in fungi cell walls), glucanases (hydrolyse glycosidic bonds in glucans) & lysozymes (degrade bacteria cell walls)
110
why are many protective chemicals only manufactures when infection is detected?
the production of chemicals requires lots of energy
111
examples of non-specific responses to disease in animals
blood clotting inflammatory response wound repair
112
examples of non-specific defences against disease in animals
mucous membranes the skin
113
other non-specific primary defences to disease in animals
eyes secrete tears which contain LYSOZYME, a hydrolytic enzyme ear wax acts as a physical barrier
114
outline mucous membranes as a non-specific defence
include airways & reproductive systems secrete mucus via goblet cells which traps pathogens cilia waft mucus
115
outline the skin as a non-specific defence
contains fibrous proteins like keratin and collagen which are insoluble and impermeable so act as physical barrier to pathogens contains sebaceous glands which secrete oils so is antibacterial
116
outline expulsive reflexes as non-specific responses
coughs/sneezes (esp. when pathogens irritate lining of airways) response is to expel them
117
outline wound repair as a non-specific response
new skin cells formed stem cells leave cell cycle and enter G0 become specialised and integrate themselves into the existing tissues scabs form while repairs are made
118
outline inflammatory response as a non-specific response
mast cells release histamines and cytokines histamines increase permeability of capillaries, causing blood plasma to leak into tissues, causing pain and swelling cytokines increase diameter of arterioles, increasing blood flow to wound and attracting phagocytes, causing redness and heat
119
outline blood clotting as a non-specific response
enzyme-catalysed cascade initiated by platelets at site of wound platelets are activated by damaged tissues to release thromboplastin, which catalyses the conversion of prothrombin to thrombin (with Ca2+ ions and serotonin). thrombin catalyses the conversion of soluble fibrinogen to insoluble fibrin, which forms a mesh of fibres that traps platelets and blood cells to form a clot
120
neutrophils adaptations
lobed nucleus enables them to change shapes and squeeze out of capillaries have lots of mitochondria, RER, Golgi apparatus vesicles in granular cytoplasm contain hydrolytic enzymes
121
what are macrophages?
differentiated monocytes
122
explain how macrophages are adapted for their function compared to monocytes
they are larger they have many pseudopodia to engulf pathogens they have more RER/Golgi apparatus/mitochondria they contain phagosomes
123
describe process of phagocytosis
pathogen engulfed into phagocyte by PHAGOCYTOSIS (type of endocytosis) into a phagosome (type of vesicle) lysosomes fuse with the phagosome to form a phagolysosome. this introduces hydrolytic enzymes e.g. lysozyme into the phagosome & digestion occurs useful products of digestion reabsorbed & waste is excreted (by exocytosis)
124
role of T helper cells in the immune response
are clonal selected by an antigen-presenting cell undergo clonal expansion some form memory cells others activate B cells
125
role of T killer cells in the immune response
bind directly to infected cells insert perforins into plasma membrane flood in hydrolytic enzymes, hydrogen peroxide and nitric acid cause cell lysis
126
role of T regulatory cells in the immune response
dampen down immune response induce apoptosis of TH, TK and plasma cells this prevents autoimmunity
127
role of T memory cells in the immune response
are clonal selected and expanded much quicker on 2nd infection by the same pathogen
128
role of B lymphocytes in the immune response
directly activated by antigen OR clonal selected by a TH cell clonal expand by mitosis some form memory cells others differentiate to become plasma cells
129
where do T cells come from?
thymus gland
130
where do B cells come from?
bone marrow
131
where do memory cells circulate?
in the spleen and lymph nodes to increase the speed of secondary immune response
132
steps of specific immune response
antigen presentation clonal selection of TH cell clonal expansion of TH cell clonal selection of B cell clonal expansion of B cell plasma cells formed and secrete antibodies
133
describe antigen presentation step in specific immune response
(macrophage becomes an antigen-presenting cell) macrophage engulfs the pathogen (antigen) and breaks it into fragments recombines antigenic fragments with its own glycoproteins & expresses the antigen on its own plasma membrane
134
how does clonal expansion occur?
by mitosis
135
how do TH cells attract B cells?
by secreting cytokines
136
what happens after clonal expansion of B cells?
B cells differentiate to form plasma cells plasma cells secrete antibodies
137
describe and explain the differences between B cell and plasma cell
plasma cell contains more RER for synthesis of antibodies (proteins) plasma cell contains more Golgi apparatus for folding 1ary structure of proteins into 4ary structure plasma cell is larger bc it contains more organelles plasma cell has more mitochondria to produce ATP for protein synthesis nucleus takes up more of the B cell's cytoplasm bc there are less organelles
138
what are antibodies?
proteins with quaternary structure
139
what are antibodies' 4 polypeptide chains
2 heavy chains 2 light chains
140
Parts of antigen structure
hinge region heavy chains light chains disulphide bonds variable region constant region
141
antibody hinge region fucntion
allows flexibility for antibody to bind to more than 1 antigen
142
antibody constant region function
same in every antibody non-specific binding say for neutrophils and macrophages
143
antibody variable region function
specific shape to antigen 2 per antigen
144
describe opsonins/opsonisation
opsonins bind to the antigen using their variable regions (marks out the antigen for destruction) neutrophil/macrophage binds to the constant region and phagocytoses the pathogen
145
what do agglutinins do?
each antibody has 2 variable regions: each variable region can attach to an antigen on a different pathogen (hinge provides flexibility): cross-links pathogens and clumps them together eases phagocytosis for neutrophils
146
what do antitoxins do?
directly binds to toxin molecules secreted by pathogens toxins neutralised, which prevents damage to cells
147
example of antitoxin treatment
tetanus bacteria secrete toxins antitoxins can be injected as a treatment
148
describe natural active immunity
bodys own response ti a new pathogen memory cells are produced
149
describe natural passive immunity
receipt of maternal antibodies through placenta or breastmilk no memory cells produced
150
describe artificial active immunity
injection of an antigen & immune response occurs memory cells produced
151
describe artificial passive immunity
injection of antibodies made by another organism no memory cells produced
152
describe artificial passive immunity
injection of antibodies made by another organism no memory cells produced
153
describe primary immune response
first encounter w/ a particular pathogen takes a few days to produce any antibodies (clonal selection/expansion of TH/B cells takes time so symptoms are felt) number of antibodies increases to a low peak and then drops rapidly PRIMARY RESPONSE has formed T/B memory cells which circulate in case of reinfection
154
describe secondary immune response
clonal selection and expansion are much faster number of antibodies increases at a greater rate and to a much higher concentration levels of antibodies stay higher for longer pathogen is removed before any symptoms are felt
155
what kind of immunity is a vaccination? why?
artificial, active immunity bc injected and prompts an immune response which results in production of memory cells
156
what are the principles of vaccination?
1. preventing severe illness which could result in death 2. promoting herd immunity 3. to promote ring immunity
157
what is herd immunity?
vaccinating the majority of a population so that disease carriers are less likely to infect a vulnerable individual
158
who cannot have vaccines?
immunocompromised people
159
what is ring immunity?
vaccinating a smaller proportion than that required for herd immunity, but vaccinating those most likely to be infected
160
what are the types of vaccine?
weakened, live pathogen dead/inactivated pathogen toxoids subunits
161
how do weakened, live pathogens work as vaccinations? examples
modified pathogen that is alive but not pathogenic mumps, polio, TB, measles
162
advantages/disadvantages of using weakened/live pathogen as a vaccine
+strongest response +long-lasting immunity -organims may revert and become pathogenic
163
how does dead/inactivated pathogen work as a vaccine? examples
pathogen killed but antigens still present influenza whooping cough
164
advantages/disadvantages of using dead/inactivated pathogen as vaccine
+stable and safer than live vaccines -response is weaker (boosters required)
165
how do toxoids work as vaccines? examples
modified toxins tetanus diphtheria
166
advantages/disadvantages of using toxoids as vaccines
+safe -may not give strong response (boosters required)
167
how do subunits work as vaccines? examples
isolated antigens haemophilus influenza B
168
advantage of using subunits as vaccine
vaccines for several strains can be produced
169
epidemic definition
disease spread across several countries in the same continent
170
pandemic definition
global spread of a disease across many continents
171
why does artificial passive immunity not provide long term immunity?
(antibodies injected) no memory cells are produced if pathogen enters body again, response will not be quick
172
why does herd immunity reduce spread of disease?
majority of population vaccinated ( many people in population have immunity so a disease carrier is less likely to come into contact with someone who is NOT immune)
173
why do vaccinations against tetanus require booster injections?
toxoid vaccinations may not give strong long-lasting response boosters maintain high levels of antitoxin antibodies & memory cells because small concentrations of toxins can be v harmful
174
suggest a barrier that makes it difficult for a virus to enter a sweet potato cell how could the virus enter the cell?
cellulose cell wall through insect transmission (vectors)
175
why are bacteria resistant and not immune?
bacteria are unicellular without an immune system immunity involves phagocytes and lymphocytes
176
why are erythrocytes containimg plasmodium more likely to be destroyed by phagocytosis than healthy erythrocytes?
produce different cell signalling molecules which attract phagocytes more strongly
177
most at risk people to disease?
elderly babies immunocompromised people
178
distinguish between an antigen and an antibody
antigen= cell-surface molecules. specific to cell and antibody antibody=immunoglobulin manufactured by plasma cells. binds specifically to antigen
179
examples of autoimmune diseases?
rheumatoid arthritis lupus type 1 diabetes
180
RHEUMATOID ARTHRITIS causes body parts affected symptoms treatments
combination of genetic and environmental mainly joints (knees, fingers, wrists) stiffened & pain due to inflammation. destruction of cartilage (joints move less smoothly) steroidal injections, NSAIDS e.g. ibuprofen, biologics
181
LUPUS causes symptoms body parts affected treatments
combination of genetic & environmental headaches, high temp, sensitivity to UV light, skin rash (butterfly shaped) skin, joints, kidney steroidal injections
182
TYPE 1 DIABETES causes body parts affected symptoms treatments
combination of genetic and environmental beta cells in pancreas destoryed thirst, weight loss, fatigue insulin injections, stem cell therapies
183
which types of antibody bind directly to antigens on the surface of pathogens?
opsonins agglutinins
184
which types of antibody increase the phagocytosis of pathogens?
opsonins agglutinins
185
following a blood test, what would indicate that a patient has lupus?
the presence of antibodies for the cell surface antigens of connective tissue
186
compare the roles of B and T lymphocytes in the specific immune response
BOTH: clonally selected, clonal expand by mitosis, can become memory cells, are specific to an antigen B: mature in bone marrow, differentiate to become plasma cells & secrete antibodies specific to antigens (T don't) T: mature in thymus, have TH/TK/Treg cells (only B), stimulate B cells to activate (B don't stim. T), secrete cytokines (B don't)
187
how do betalain pigments interfere with the action of cytokines
prevents cytokines form binding to receptors on the membranes of their target cells