Infection and Response Flashcards
What are pathogens?
Microorganisms that enter the body and cause disease.
What are the 4 types of pathogens
Bacteria
Viruses
Protists
Fungi
What are bacteria and what do they do?
Very small cells that can reproduce rapidly in the body generate toxins to damage host cells and therefore cause symptoms of disease.
What are viruses and what do they do?
Microorganisms which infiltrate the host cells and uses the host’s cells machinery to replicate and therefore infect and spread across the host’s body.
Compare the size of the virus with the size of the bacterial cell?
Viruses are about 1/100 of a bacterial cell.
What are protists and what do they do?
Unicellular Eukaryotes that may act as parasites.
How do protists cause disease?
Live on or inside the host to cause disease.
How are protists transmitted into the body of the host?
Protists are often transmitted via the use of vectors e.g. insects
What are fungi and what do they do?
Unicellular or multicellular organisms (hyphae) that can cause disease.
What is a hyphae?
Filamentous structure on the body of the fungus.
How do hyphae cause disease?
Hyphae can grow and penetrate the surface of human skin and plants, transmitting material to cause disease.
Hyphae can also produce spores which can be spread to other plants and animals.
What are the different ways pathogens can be spread?
> Water droplet
Air
Direct contact
What are some examples of viral diseases?
> Measles
HIV
Tobbaco Mosaic Virus
How are measles spread?
Via air droplets (sneezing, coughing)
What symptoms do patients with measles present?
Red rash, fever,
Why can measles be fatal?
Measles can be fatal if it spreads to other regions of the body e.g. lungs (causes pneumonia), brain (encephalitis).
How can measles be prevented?
Vaccination
When does measles vaccination take place
During early childhood
How is HIV spread?
> Sexual contact
Exchange of bodily fluids
Sharing dirty needles
How do patients with HIV clinically present?
Initially in the first 2 weeks, patients present with flu like symptoms, however these symptoms disappear.
Roughly 2-5 years later, the patient starts to become infected much more frequently. This is because during the 2-5 years, the immune system is weakened by the virus itself (HIV causes immune cells to burst, thereby destroying it).
How can HIV be prevented/controlled?
> Antiretroviral drugs - stops the viral cell from replicating within the body,
Protective wear during sexual activity e.g. condoms
Usage of clean needles
What does Tobbaco Mosaic Virus cause?
Causes a mosaic pattern on the leaves of plants, rendering parts of the plants discoloured.
What is the effect of TMV?
TMV causes discolouration which leads to a decline in photosynthetic activity, rendering the plant stunted of growth.
What is an example of a fungal disease?
Rose Black Spot
How do plants with rose black spot present?
Purple/Black spots on rose leaves, which turn yellow and fall off.