B6.3 - Monitering And Maintaining Health Flashcards
What is a communicable disease and example
Can be spread between organisms. Eg. Athletes foot, tuberculosis, crown gall disease, tobacco mosaic
What is a non-communicable disease
One that cannot be spread between organisms. E.g. diabetes, unhealthy diet, cystic fibrosis
What is HPV
Human papilloma virus is a cell change that causes cervical cancer that is usually in girls
What is HIV
human immunodeficiency virus weakens a persons immune system as virus replicates in white blood cells. Unable to make antibodies and causes AIDS and tuberculosis due to tuberculosis causing bacteria
How can pathogens spread in animals
- through the skin : open cuts and wounds
- through digestive system: eating food and drink
- through respiratory system : breathing it in and inhaling
- through reproductive system: sexual intercourse and exchange of bodily fluids
How do pathogens spread in plants
- vectors such as insects
- direct contact with the sap of infected plant with healthy plant
- wind. Airborne fungal spores and spread disease.
Incubation period
The time delay from which the harmful microorganisms enter your body and time you start feeling unwell.
How do viruses replicate
- the virus attacks a cell
- the virus attaches and transfers it’s gene
- it tells the nucleus to copy its genes
- new viruses are made
- the cell bursts and viruses released destroying the cell
Incidence of a disease
Rate at which new cases occur in population over a period of time.
How to prevent spread of communicable disease
- cover your mouth when coughing or sneezing
- do not touch infected people or objects
- no sharing of needles (disease passed through blood)
- using protection (prevent exchange of bodily fluids)
General hygiene
- wash hands
- cook food properly to inhibit food poisoning through e.coli and salmonella
- drink clean water
- protect from animal bites
How do farmers prevent spread of communicable disease
- livestock not moved
- plants burnt to prevent spread
- given drugs however sometimes herds slaughtered
- chemical dips given for farmers footwear to kill pathogens
Human infections - fungal
Athletes foot is caused due to fungal infections of parasitic fungi ‘dermatocytes’ with hot, humid and wet environment. Causes itchy, red and flaky skin and is highly contagious from skin to skin contact. Fixed with anti-fungal cream.
Human infection - bacteria
food poisoning is caused due to growth of microorganisms in food such as salmonella and e.coli, in unpasteurised milk, raw meat, uncooked food and dirty vegetables. Causes vomiting, diarrhoea however fixed in few days and must freeze food.
Human infection - STI’s from unprotected sex and genital contact
- chlamydia; painful when urinating and discharge - antibiotics
- gonorrhoea; pain when urinating and vaginal discharge - antibiotics
- genital herpes; blisters and sores - no cure (virus)
- HIV; weaken immune system with AIDS - no cure but use antiretrovirals
What is HIV and AIDS
Human immunodeficiency virus causes weakened immune system as virus replicates in white blood cells. This means, cells that produce antibodies will not be able to and becomes target of everyday infections and unable to fight. AIDS is the final stage when body no longer able to fight.
Plant diseases - virus
Tobacco mosaic disease is when the virus attacks leaves making them mottled and discoloured. It prevents the chloroplasts from forming which stunts the growth and decreases the yield with lower quantity and quality.
To prevent - plants are removed and only crops that are resistant should be planted in infected areas.
Plant disease - bacteria
Crown hall disease formed when bacteria (A. tumefaciens) enters through wound. The large plasmid of bacteria integrates with host’s genome and produces a growth of chemicals that is much more than needed. This leads to a tumour like growth as ‘galls’. This carries on and encircles the stem and trunk cutting the flow of sap. Causes stunted growth and eventual death.
To prevent - infected plants should be destroyed and removed and other susceptible plants should be avoided for 2 years until bacteria dies out without host plant.
Plant disease - fungal
Powdery mildew is fungal disease due to high temp and humidity, where white powdery spots form on plants leaves. Through wind, where fungal spores are blown and reduces growth and makes leaves drop early whilst reducing crop yield by 10-15%.
To prevent - spraying crop with fungicide.
Physical plant defences
Physical barriers that prevent microorganisms entering
Chemical defences
Substances secreted by the plant that kill microorganisms
Physical defence examples
Waxy Cuticle - prevents water loss from plant and prevents pathogens from coming into direct contact with epidermal cells and limits chance of infection. This is because they are hydrophobic and made from fats and lipids which prevents water and fungal infections from germinating.
Cell wall - physical barrier provides structural support through cellulose fibres. These are cross linked with substances such as pectin which forms a gel to cement neighbouring cells together.