P1 - Infection and Response Flashcards
What are pathogens ?
Microorganisms that enter the body causing communicable diseases, they can affect both plants and animals. For main types are: bacteria, viruses, protists and fungi.
What are bacteria ?
Very small cells (1/100th the size of body cells) which reproduce rapidly in the body, make you feel ill by producing toxins that damage cells and tissues.
What are viruses ?
Not cells, tiny (1/100th size of bacterium) reproduce rapidly inside body cells which eventually burst releasing the new viruses. Cell damage is what makes you feel ill.
What are protists ?
Lots of different types, all eukaryotes and most are single celled, some are parasites which live on/in the organism and can cause damage.
What is a vector ?
Transfers protists to an organism, but doesn’t get the disease itself.
What are fungi ?
Some are single celled, some have a body made up of hyphae - thread-like structures, which can grow and penetrate human skin causing disease. Hyphae can produce spores which can spread to other plants and animals.
How can pathogens be spread ?
Some are through water, air and direct contact.
What is measles ?
Viral disease spread by droplets from sneeze or cough of infected person, causes red skin rash, signs of fever. Most people are vaccinated against measles when they’re young.
What other things can measles cause ?
It can be very serious or even fatal if there are complications, it can lead to pneumonia or a brain infection called encephalitis.
What is HIV ?
Virus spread by sexual contact or exchange of bodily fluids, causes flu-like symptoms initially, then nothing for a few years but the HIV virus still attacks the immune system which if badly damaged can’t cope with other infections or cancers. At this point it’s known as late HIV or AIDS.
What can be done to help against HIV ?
During the period where they don’t experience any symptoms the person can take antiretrovial drugs to stop the virus replicating in the body.
What is tobacco mosaic virus ?
TMV is a virus that affects plants, causing mosaic pattern on the leaves of discolouration - meaning plant can’t carry out photosynthesis as well. Virus affects growth.
What is rose black spot ?
A fungus that causes black spots to develop on leaves of roses, which can then turn yellow and drop off - reducing amount of photosynthesis, affecting growth.
How is rose black spot spread and how can it be stopped ?
Spreads through water or wind, can be treated using fungicides and by stripping plant of affected leaves, and then destroying them to stop the spread of fungus.
What is malaria ?
P84
