disease etc ( year 12 ) Flashcards
pathogens are passed around by plants via …
spores
ways of preventing spread of pathogens etc.. .
leave plenty of room between plants- minimises spread of pathogens
.clear fields thoroughly to remove traces of plants from soil at harvesting
.roate crops, so bacteria will eventually die if they dont ahve access to host plant
.follwo strict hygiene practices- eg washing hands and machinery etc…
.control insectvectors
how do histamines contribute to the inflammatory response
.dilate blood vessels- raised temp prevents pathogens reporduction
.makes blood vessel walls leka thus blood plasma forced out, now its tissue fluid which caues swelling and pain
.
.cytokines- attract white bood cells to site- dispose of pathogens via phagocytosis
how do fevers get rid of pathogens ?
high temp, inhibit pathogen reproduction
.specific immune system- works faster at higher temperatuers
mhc
glycoproteins !
passive immunity
antibodies cross mothers placenta from mother to fetus . milk is made from coostrum - high in antibodies- gut allows these glycoproteins to pass into blood stream without digestion
.within few days of birth- breast fed baby has antibody protenction-
natural passive immunity because it lasts until immune system of baby begins to make its own antibodies
the process of blood clotting !
When you cut yourself:
-Platelets come in contact with collagen in the skin
-Platelets stick to each other
-Secrete several substance
Thromboplastin – enzyme that leads to the formation of a blood clot
Serotonin – causes smooth muscle in walls to contract (narrowing reduces blood supply to area
-Clot dries out, forming a hard, tough scab
-Epidermal cells below start to grow, sealing wound permanently
-Damages blood vessels regrow
-Collagen fibres deposited to give new tissue strength
whats inside pathogens ?
.dead pathgoens
weakened pathoens
detoxified toxins
isolated antigens
genetically engineered antigens
pharmacogenomics
mediciens tailored to dna , because we already know how drug and genomes interact
synthetic biology
used to make drugs in large quantities that would other wise be way too expensive or rare to make
bacteriophafges
virus that attacks bacteria by taking over them and replicating them
what do bacteria + fungitoxins do
inactivate host enzymes, interfere w genetic material so cells cant divide
green box: a threat to english oak trees
exposed to diseasde - acute oak decline - scientist dont know the cause - diffuciult to understand spread
.evidence: discovery of unknown bacteria in tree - plays role in disease
.beetle activity- acts as vectors
preventing spread of communicable disease in plants
leave roo mebtween
.clear fields
.rotate crops
.follow hygiene practices
.control insect vectors
chitinases
anti oomycetes
antifungal compoiund breaks chitin wall
glucanases- enzymes made by osme plants- break down glucans- polymers found in cell walls of oomecytes
non specific defenses
skin- sebum inhibits growth
.mucus membranes - traps pathogens
.lysozomes- tears and urine- digest pathogen
.coughs and sneeizng
examples of non specific defenses
blood clotting
inflammatory response- histamines, cytokine
fevers- kills pathogens using heat
autoimmune diseases
type 1 diabetes - affects insulin secreting cells- treated with insulin injections, pancreas transplants, drugs
rheumatoid arthritis - affects joints, no cure, anti inflammatory drugs, immunosuppresants, pain relie
lupus- affects skin and joints—> fatigues
.attacks any organ in body eg kidneys liver etc. no cure, anti inflammatory drugs, steroids and immunosuppresants needed
there is no cure for
malaria and HIV
how do we make vaccines for pathogens
complex computer programmes using 3d models of key molcules and computers used to search through chemical libraries
analysis of genomes of pathogens and genes linked to cancer
disadvantages of making new medicines using plants etc..
destroys biodiversity
the antibiotic dilemma
problem with making them so that they dont interfere with bacteria metabolism- called selective toxicity
solving the problem
fear that we could return to days hwere bacterial infection killed loads of people - so scientists developing new antibiotics and using sources eg crocodile blood, fish slime, honey and ocean abysses
competitions for best, cheap way to test for bacterial infections
glucanases
plant chemcial released to break down glucans (polymers in oomecyte cell walls )
