3-Infection And Response Flashcards
What is pathogen
Microorganisms that cause communicable diseases
What do bacteria do
Produce toxins that make feel ill
Can reproduce rapidly inside body
What do viruses do
Live inside host cells and replicate rapidly
The cell then bursts and the cell damage makes you feel ill
Not cells
How big are bacterium
Very small cells 1/100th size of body cells
How big are viruses
1/100th size of bacterium
What are protists
Mostly single celled eukaryotes
Some are parasites
Often transferred through a vector
What are fungi
Some are single celled and others have a body made up of hyphae.
These hyphae can grow and penetrate human skin and surface of plants causing disease
Hyphae produce spores which can spread to other plants or animals
How can pathogens spread
Water
Air
Direct contact
How r pathogens spread through water
Drinking or bathing in dirty water
eg. Cholera
How r pathogens spread the air
Carried in the air and breathed in
eg. Influenza
How r pathogens spread through direct contact
Touching contaminated surfaces including skin.
eg. Athletes foot can be spread through shower floors and towels
What does measles cause
Red skin rashes, fever, sometimes lead to pneumonia or encephalitis (a brain infection)
How is measles spread
Droplets from an infected person’s sneeze or cough
What does HIV cause
Flu like symptoms for a few weeks but the person doesn’t then experience any symptoms for several years after. The virus attacks immune cells so the body can’t cope with other infections
What does tobacco mosaic virus cause (TMV)
Causes a mosaic pattern on the leaves of plants and part become discoloured
What does discolouration cause in leaves
The plant can’t carry out photosynthesis as well so affects growth
What does rose black spot cause
Purple or black spots on the leaves of rose plants.
They then turn yellow and drop off
How does rose black spot spread
Water and wind
How can rose black spot be treated
Fungicides or cutting off affected areas
How is malaria spread
Through the vector mosquito
They pass on the disease when they feed on an animal
What does malaria cause
Repeated episodes of fever that can be fatal
How can malaria be treated
Protection from mosquitoes through using insecticides and mosquito nets
What does salmonella cause
Food poisoning
Fever, stomach cramps, vomiting and diarrhoea
How is salmonella caught
Eating food that’s been contaminated with the salmonella bacteria
How is the spread of salmonella reduced
In the UK most poultry is vaccinated against salmonella
What does gonorrhoea cause
Pain when they urinate.
Thick yellow or green discharge from vagina or penis
How is gonorrhoea transmitted
It’s and STD so is spread through sexual contact
How is gonorrhoea treated
Antibiotics can treat it however strains of bacteria have become resistant to penicillin.
To prevent spread of it barrier methods of contraception should be used
What are the 4 main ways to reduce or prevent disease
Being hygienic,
Destroying vectors,
Isolating infected individuals,
Vaccination
How does the skin prevent disease
Barrier to pathogens and it also secretes antimicrobial substances which kill pathogens
How do hair and mucus in the nose prevent disease
They trap particles that contain pathogens
How do the trachea and bronchi prevent disease
They secrete mucus that trap pathogens and they are lined with cilia which push mucus up to the back of the throat to be swallowed
How does the stomach prevent disease
Produces HCL which kills pathogens
What is phagocytosis
When phagocytes (a type of white blood cell) engulf foreign cells
What r the unique molecules on the surface of a pathogen called
Antigens
How r antibodies produced
When lymphocytes come across a foreign antigen they produce antibodies that lock onto the antigen and kill it or notify phagocytes to engulf it
When r lymphocytes called B-lymphocytes
When they can no longer divide
What is used in vaccines
Dead or inactive pathogens
What r advantages of vaccination
Control lots of communicable diseases that use to be common.
Herd immunity- when the majority of population is vaccinated so the disease doesn’t spread
Disadvantages of vaccination
Don’t always give immunity.
Can have a bad reaction to the vaccine but this is very rare
What do painkillers do
Reduce symptoms of disease but don’t actually treat it
What do antibiotics do
Kill the bacteria causing the disease.
Do not destroy viruses
How can bacteria become resistant to antibiotics
The bacteria can mutate and cause them to be resistant to the antibiotic.
It then reproduces
How do you reduces the rate of antibiotic resistance
Important for doctors to not over prescribe antibiotics.
And the patient needs to finish the whole course of treatment
What is aspirin and where does it originate
Used as a painkiller and to lower fever.
Developed from chemical in willow
What is digitalis and where does it originate
Treats heart conditions.
Developed from chemical in foxglove
What r the main stages of developing drugs
Tests on computers, Tests on human cells and tissues in the lab, Tests on live animals, Healthy human volunteers, Ill human volunteers, Patients put in two groups and one has a placebo, The trails are blind, Peer review
What r the B-lymphocytes combined with to make a hybridoma
Tumour cells because then it can divide as well
What are monoclonal antibodies
Cloned hybridoma cells that all produce the same antibodies
What hormone is found in the urine of a women only when they are pregnant
HCG
Why does the pregnancy strip turn blue when pregnant
Because the hormone in the urine binds to the antibodies on the blue heads.
And then the urine moves up the strip and it binds with the antibodies stuck on the strip turning it blue as the blue heads get stuck on the strip
How r monoclonal antibodies used to treat tumour cells
Anti cancer drugs can be attached to the monoclonal antibodies which can target the cancer cells and bind to the tumour’s antigens
How can monoclonal antibodies be used in labs to find specific hormones, chemicals, pathogens or molecules in a cell
Fluorescent dye is added to specific antibodies and they attach to them and could be detected
What r the side affects of monoclonal antibodies
Fever, vomiting and low blood pressure
What does nitrate deficiency cause
Needed to make proteins so it causes stunted growth
What does magnesium deficiency cause
Needed to make chlorophyll so plants suffer from chlorosis and have yellow leaves
What r common signs of plant disease
Stunted growth Spots on the leaves Patches of decay Abnormal growths Malformed stems or leaves Discolouration
How can plant diseases be identified
Looking up signs in garden manual or website,
Taking infected plant to laboratory,
Testing kits that use monoclonal antibodies
What physical defences do plants have
Waxy cuticle
Cell wall
Layers of dead cells round stems
What chemical defences do plants have
Produce antibacterial chemicals,
Produce poisons
What mechanical defences do plants have
Thorns or hairs,
Droop or curl when something touches them,
Mimic other organisms
