Topic 3: Infection And Response Flashcards
When are infections caused?
Whenever a foreign pathogen invades an organism.
Name the 4 main types of pathogen
Virus
Bacteria
Protist
Fungi
What are visuses?
Tiny, non-living particles that can reproduce rapidly within the body.
What do viruses NOT contain?
Cells
What type of cells to viruses invade it make new virus particles?
Host cells
What do viruses cause the cells to do when they are made?
They make the cells burst, and the cell damage makes us feel ill.
What are Bacteria?
Small living cells that either damage cells directly or by producing toxins (poisons).
What are the optimal conditions for bacteria to reproduce rapidly?
Warm, moist areas with a good supply of oxygen.
How do bacteria make us feel ill?
By releasing toxins which damage cells and tissues.
What are Fungi?
Single-celled organisms that have a body made up of hyphae (thread-like structure)
What is the hyphae (thread-like structures) found in fungi able to do?
Grow and penetrate tissues, such as human skin.
What do hyphae in uni product so they can spread to other plants and animals?
They produce spores/
What are Protists?
Single-called eukaryotic organisms
What does it mean if a organism is eukaryotic?
It has a nucleus/
What does it mean if something is a parasite?
That they live on or inside other organisms.
How are protists transferrred to the host organism?
By a vector (e.g a mosquito for malaria)
How do protists make us feel ill?
By damaging our tissues
What are the 3 ways an infectious disease can spread?
Direct Contact
Water
Air
Name 1 example of a disease that spreads through direct contact.
Athletes foot
Name 1 example of a disease that spreads through water?
Cholera.
Name 1 example of a disease that can be spread through air?
The flu
Name 4 ways we can prevent infection spread.
Practising good hygiene
Isolation
Deterring vectors
Vaccination
What do vaccines do?
Make people immune (resistant to) infection, so the disease is less likely to spread.
What are viruses?
tiny, non-living particles that reproduce rapidly within the body.
Name 3 examples of virus diseases.
Measles
HIV
TMV
What are the symptoms of measles?
fever
red skin rash
How is the measles virus spread?
By breathing in droplets from coughs etc.
What does HIV stand for?
Human Immunodeficiency Virus
How is HIV spread?
Through sexual contact or the exchange of body fluids.
What happens if you have HIV and the antiretroviral drugs did not work properly?
The virus enters the lymph nodes and attacks the body’s immune system.
What is AIDS caused by
HIV
What does TMV stand for?
Tobacco Mosaic Virus
What is the symptom of Tobacco Mosaic Virus, and why does this symptom occur?
Discolouration, due to photosynthesis not being able to take place.
Are viruses cellular or acellular?
acellular
Do viruses reproduce rapidly or slowly?
rapidly
do viruses need a host cell?
yes of course
are viruses living or non-living?
non-living
what are the 4 steps of viruses in the body?
INVASION (virus invades the host cell)
REPLICATION (the particle inserts its DNA into the cells DNA, this is replicated)
INVADED CELLS BURST (cells are burst to allow them to invade more cells)
ILLNESS (cell damage makes the person feel ill)
What are bacteria?
small living cells that either damage cells directly or by producing toxins
What are toxins?
poisons
Name 2 examples of bacterial diseases.
Salmonella
Gonorrhoea
What do the toxins from salmonella cause?
Vomiting, fever, stomach pain and diarrhoea
What is Gonorrhoea?
A sexually transmitted disease.
What are the symptoms of Gonorrhoea?
pain when urinating and a thick yellow or green discharge from the penis or vagina
What can be used to stop the spread of Gonorrhoea?
barrier contraception methods incl. condoms
What are fungi?
a unicellular or a multicellular organisms with bodies maid up of hyphae (which are thread-like).
What are the hyphae of fungi able to do?
grow and penetrate tissues
name an example of a fungal disease.
Rose Black Spot.
What does a fungi’s hyphae produce?
spores which can spread.
How is rose black spot spread?
in water or in the air
How is rose black spot treated?
by cutting off affected leaves etc.
What are protists?
single-celled eukaryotic organisms
What are parasites?
things that live on or inside an organism
Name an example of a disease caused by a protist.
Malaria
many protists are…
… parasites
