B3 Flashcards
What is a pathogen?
a microorganism that causes disease
What are the four types of pathogens?
- protists
- viruses
- bacteria
- fungi
Give three ways that pathogens can be spread between people?
- through the air- breathed in or spread by airborne droplets e.g. influenza virus
- direct contact e.g. athlete’s foot
- water- drinking or bathing in dirty water e.g. cholera
Give three viral diseases
- Measles
- HIV
- Tobacco Mosaic Virus(TMV)
What is Tobacco Mosaic Virus?
a virus that can be transmitted by direct contact between plants (naturally or by the hands of farmers) which infects the chloroplasts of plant leaves and changes their colour from green to yellow or white in a mosaic pattern
- reduces the plant’s ability to photosynthesise and grow properly, which reduces the crop yield for farmers
What happens when a plant has a nitrate deficiency?
Stunted growth
What happens when a plant has a magnesium deficiency?
yellow leaves (discolouration) because magnesium helps with chlorophyll production
What is HIV and how can you treat it?
a viral disease that is spread by unprotected sex, sharing needles or infected blood. It attacks white blood cells and can develop into AIDS
antiretroviral drugs
Why might someone with AIDS take longer to recover from salmonella?
Their immune system would be weakened so their white blood cells would not be able to destroy the bacteria
Name a fungal disease
Rose black spots (causes purple/black spots to form on the leaves of roses)
How are protists usually transported?
By vectors (other organisms that do not get the disease)
What is a parasite?
An organism that depends on another organism to grow and reproduce
What is malaria caused by?
Malaria is caused by parasitic protists which means it needs a host to survive, transported between hosts by mosquitos.
Give symptoms of malaria
- high fever
- pain
- diarrhoea
- vomiting
- sweat and chills
Give two bacterial diseases and two symptoms of each
Salmonella
- fever
- stomach cramps
- vomiting
- diarrhoea
Gonorrhoea
- thick yellow/green discharge
- pain when urinating