INFECTION & RESPONSE Flashcards
Communicable disease
diseases that are spread between people, are caught, and cause infection and are caused by pathogens
pathogen
Micro-organisms which cause disease
prokaryotic
does not have a nucleus or membrane bound organelles
vector
a carrier of a parasite but is not infected by it
host
carries disease inside cells
antibody
specialised protein molecule which binds specifically to antigen
process of phagocytosis
solid substances/ whole organisms brought inside cell via invagination - engulfed
Vacuole formed - inner surface derived from outer surface of cell membrane - the membrane is the phagosome
Bacteria destroyed by enzymes
b-cells
When antigens are removed, the pathogen is ineffective - has been neutralised - Remain in organs of immune system - ie spleen, thymus - send antibodies to infection - Each lymphocyte produces one type of antibody
t-cells
Toxins cause symptoms of illness
Antitoxins bind to toxins to prevent feelings of illness - alleviate symptoms
T-cells travel from immune system organs to infection to release complimentary antitoxins to neutralise toxins
Bactericidal antibiotic:
kills/destroys bacteria
Bacteriostatic antibiotic
stops bacteria growing/reproducing
efficacy
does it work to kill pathogens/reduce symptoms/prevent disease
dosage
how much should be used and for how long
toxicity
is it safe - it shouldn’t kill cells or cause serious side effects
double-blind trial
subject and researcher don’t know whether the drug or a placebo has been given - Eliminate researcher bias, Avoid unreliable results/Bribery, Avoid placebo effect
parts of a bacteria
Flagellum, nucleoid (bacterial DNA), cell membrane, cell wall, capsule, cytoplasm, plasmid
symptoms of salmonella
Fever, stomach cramps, diarrhoea, nausea, vomiting, chills, headache
causes of salmonella
Eating food contaminated with animal faeces
Contact with infected animals
Door handles
treatment of salmonella
Separating raw meat and poultry from produce
Washing hands/boards/cutlery/utensils/fruit&veg
Antibiotics
Drink extra fluids
symptoms of gonorrhea
Pain, discomfort, bleeding outside of periods, unusual discharge
causes of gonorrhea
Infected bodily fluids during intercourse
prevention and treatment of gonorrhea
Antibiotic injection
Condoms
Not sharing sex toys
anatomy of a virus
protein molecules, capsid, DNA or RNA (nucleic acid), envelope protein
symptom of HIV
Fever, fatigue, swollen lymph nodes, diarrhoea, weight loss, pneumonia
cause of HIV
Sexual contact with infected partner
Blood contamination
Treatment of HIV
Antiretroviral therapy
Condoms
Not sharing needles
Preventative medicines
Limit sexual partners
symptoms of measles
High fever, cough, runny nose, watery eyes, rash
spread of measles
Coughing, sneezing - direct contact with nasal or throat secretions
treatment of measles
Painkillers
Vaccination
Wash hands
Use tissues
symptoms of rose black spot
purplish/black spots on upper leaf surface
Yellow leaves
Dropping leaves
spread of rose black spot
Spores in wind/water
treatments of rose black spot
Fungicides
removing/destroying infected leaves
Not planting roses too close together
symptoms of malaria
fever , chills, headache, nausea, muscle aches, anaemia, jaundice
treatment of malaria
Long sleeved clothing, mosquito nets
Covering water sources
Spray water sources with insecticide
Preventative medicine
life cycle of malaria
Person is bitten - saliva injected into person
Parasites travel through blood stream to liver - reproduce rapidly
Every 4-5 days burst out of liver cells, destroying them, infect new cells
Cycle repeats
eukaryotic vs prokaryotic
E: Nucleus, Mitochondria, Cytoplasm, Cell membrane, ribosomes
P: Nucleoid, Flagellum, Capsule, Cytoplasm, Cell membrane, ribosomes
function of skin
Barrier to prevent pathogens entering body - Sweat, epithelial cells, scabs, blood clots, Sheds, waterproof, Specialised immune cells in skin tissue, Secretion of sebum (anti-microbial)
how pathogens can enter body through skin
Cuts in skin
Bites
contact/absorption
function of nose
Stops pathogens entering body, traps & ejects them - Ciliated cells, Mucus, Sneezing, Hairs
how pathogens can enter body through nose
Breathing it in
function of trachea/bronchi
Catch & eject pathogens to stop them entering body - Cilia, Coughing
function of stomach
HCl acid -> Kills pathogens
function of eyes
Barrier and removal method for pathogens - Tears - contain lysozyme - damages bacterial cells, Eyelashes
defence mechanisms of reproductive organs
Physical barrier - epithelial cells, Uterus lined with acid, Secretion and bodily fluids with antibacterial agent
defence mechanisms of mouth
Saliva contains antibodies - also washes bacteria into stomach & then vomit, Oral mucosa
process of vaccination
- Weakened or dead form of pathogen injected into body - cannot cause serious disease 2. Phagocytes engulf pathogen - display antigens on surface of cells 3. Phagocytes go to lymph glands - locate B-cells 4. B-cells cloned by mitosis 5. B-cells produce antibodies - send into blood stream 6. Antibodies immobilise antigens - cannot infect any more human cells 7. B-cells become memory cells - if exposed again, will recognise pathogen immediately, producing antibodies in large numbers so no symptoms occur
what is different in 2nd exposure to disease
More antibodies - there are more T & B cells as memory cells, so more antibodies can be produced; Antibodies made faster - memory cells remember pathogen antigens - does not have to locate T & B cells - more T & B cells to produce them; Antibodies last longer - more of them are made
causes of antibiotic resistance
Using antibiotics to treat a virus
Preventative use in farming
Not finishing a course
Not taking a high enough dose
Not taking antibiotics specific to bacteria causing illness
process of antibiotic resistance
- Normal bacteria 2. Random mutation occurs which makes 1 bacterium resistance to antibiotic 3. Initially, mutation has no advantage 4. If antibiotic used, unadapted die - resistant have advantage and survive 5. Resistant reproduce and pass resistance to offspring and become dominant species
examples of, function, problems with: antibiotics
Penicillin, methicillin, ampicillin
Kill bacteria
Resistance
examples of, function, problems with: painkillers
Ibuprofen, paracetamol, aspirin
Reduce symptoms
Addictive
examples of, function, problems with: antiretroviral
COVID, malaria
Destroy viruses
Not effective
digitalis source and use
foxgloves - heart disease
penicillin source and use
Penicillium mould - Discovered by Fleming - antibiotic
aspirin source and use
From willow - Painkiller
preclinical drugs testing
Using donated cells - Looking for efficacy and toxicity
Using donated tissues - Testing for efficacy and toxicity - Larger sample of cells to increase accuracy
Using live animals - Testing for efficacy and toxicity within a whole organism
clinical drugs testing
Healthy volunteers - Testing toxicity - side effects - Low dosage
Patients - Start small (10-50) then large no.patients (10000) - Testing efficacy and dosage
evidence of plant disease
- Stunted growth
- Spots on leaves
- Areas of decay
- Unusual growths
- Malformed stem/leaves
- Discolouration
- Presence of pests
TMV symptoms
Pattern of light & dark green on leaves, Malformed leaves, Yellow streaked leaves, Yellow veins - Less chlorophyll -> Harder to photosynthesise
TMV causes
Worker’s hands/tools/clothes/Contact with animals
Leaves rubbing together
TMV treatment
Destroy infected plant
Use sterile equipment
Rotate crops
result of mg deficiency
Can’t make chlorophyll -> cant absorb light -> cant photosynthesise -> cant create glucose -> cant release energy/respire -> cant survive/grow
result of nitrates deficiency
Nitrate + glucose -> amino acids
Cant make proteins so cant grow
acacia defences
Lots of thorns, High crown
Avoids short animals, Deters sensitive animals
nettle defences
Stinging hairs - Deters sensitive animals
pebble plant defences
Mimics rocks - Camouflage
passion flower defences
Mimics butterfly eggs - Stops butterflies laying there
bracken defences
Poisons in leaves that cause cancer/blindness - Poisons herbivores
mimosa plant defences
Rapid movement - Avoids herbivores
dead nettle defences
Looks like nettles - Tricks herbivores
production of monoclonal antibodies
- Mouse is vaccinated to start formation of antibodies 2. Spleen cells that form antibodies are collected in operation 3. Fused with tumour cells called myeloma cells 4. Forms hybridoma cells 5. Grown in lab - those that produce antibodies are separated 6. Antibodies are collected
mAbs and pregnancy kits
- Urine passes through reaction zone
- HCG hormone attaches to mobile antibodies
- HCG also attaches to immobilised antibodies
- HCG that does not bind to antibodies will only attach to antibodies in control zone
- Blue lines appear
measuring antigens with mAbs
- Line test tube with antibodies
- Add blood
- Antigens bind to antibodies
- Add more antibodies (same as 1) with enzyme attached
- If blood contains antigens, antibodies will also bind to antigens
- Rinse away anything that didnt bind
- Add substrate that causes colour change
