B5 Flashcards
what is health
health is the stat of mental, physcal and social well being
whats a communicable disease
a disease whch can pass from one person to another
whats a pathogen
they are microorganisms which and infect animals and plants and cause dieases
what is a non-communicable disease
a disease which can not spread frfom one person to another
how do bacteris make us feel ill
they relaes toxins whch harm our body
how do viruses make us feel ill
virus need host cells to reproduce so they use our cells to reproduce and in doing so they damage our cells because they burst out of our cells
how can patgogens spread from one person to another
air particles, food and water, direct contact, indirect contact, insect bites
what are 3 thngs found in agar jelly when growing bacteria
glucose, proteins, oxygen
at what rate do bactera grow
once every 20 minutes
what is the process of bacteria multiplying called
binary fission
how do you prepare a bacteria culture
Sterilise the inoculating loop by passing it through a
Bunsen burner flame until it is red hot. Let it cool, do not put the
loop down or blow on it to cool it
Step 2: Dip the sterilised loop into the suspension of bacteria you
would like to grow, use the loop to make zigzag streaks across
the surface of the agar. Replace the lid on the dish as quickly as
possible to avoid contamination.
Step 3: Fix the lid of the Petri dish wish tape to prevent
microorganisms from the air contaminating the culture – or
microbes from the culture escaping. Do not seal all the way
around the edge as oxygen will still need to enter so that bacteria
can respire and grow.
Step 4: The Petri dish should be labelled and stored upside down
to stop condensation falling on the agar surface. The dish should
be kept in an incudabotr set at 25⁰C.
why are bacteria cultures kept at 25 degrees at school
so the bacteria dont grow uncontrollably and dont turn into harmful pathogens
how would you calculate the area of bacteria growing on agar jelly
youd use pi X r squared
how do vaccines work
they use a dead or unactive pathogen and inject it into our bodies so that our immune system can fight off the disease by producing anitbodies so when that pathogen tries to infect our body the immune system can fight it off
what is an antibody
a special protein made which is made in order to fight off antigens
what is an anitgen
an antigen is a protein found on the surface of a pathogen
what are antitoxins
a substance which counteracts the harmful toxins produced by pathogens
name 2 bacterial diseases and how they’re spread
salmonella - through food either being undercooked or being prepared in unhygenic conditions
gonorrhoea - through sexual contact
what are the symptoms and treatments of gonorrhoea an salmonella
salmonella can cause fever, abdominal cramps, diarrhoea and vomiting. the spread can be reduced by vaccinating poultry against it. if you do get it you can have antibiotics
gonorrhoea - thick yelow or green discharge from the penis or vagina and pain during urination. it can be treated by antibiotics and using condoms.
what are some viral diseases and how are they spread
measles - air droplets
TMV - direct contact or by some vectors
HIV/AIDs - sexual contact and unscreened blood transfusions
what are the symptoms and treatments of the viral diseases
measles - fever, red rash - there is no treatemnet but spread can be reduced by vaccinations
TMV - mosaic discolouration on the leaves - no treatment but the spread can be reduced by having good field hygeine and grow TMV resistant crops
HIV/AIDs - flue like symptoms - can be slowed done by taking anti retroviral drugs and spread can be reduced by using condoms
what are some fungi and protist diseases and how are they spread
rose black spots - spread by water or wind
malaria - spread by vectors
what are the symptoms of the fungal and protist diease and how can they be treated
rose black spots - purple or black spots on the leaves - can be treated by fungicide and removing/destroying the leaves
malaria - chills, high fever, sweating, headaches - can be treated by some drugs. spread can be reduced by using mosquito nets when sleeping and stopping vectors breeding by using insecticide or having the malaria vaccine
what are 2 types of white blood cells that fight off pathogens and how do they work
phagocytes - engulfs the bacteria and uses hormones to break them down
lymphocyte - creates antibodies and antitoxins
what are some chemical defences our body has to protect us from pathogens (1st line of defence)
HCL acid in our stomach, tears and saliva have antibacterial enzymes
what are some physical defences of our body against our pathogen (1st line of defence)
skin - prevents entry of pathogens into our body
mucus and earwax - traps dirt and pathogens from entering our body
how do vaccines work
Pathogens in the body are recognised by the immune system because of foreign ANTIGENS on their surface. White blood cells learn to make specific antibodies for this pathogen. Pathogens destroyed (antibody – antigen interactions).
Next infection from same pathogen is defeated quickly because the body remembers which antibodies are needed.
