B3 Viral, Fungal and Protist Diseases (page 44) Flashcards
What Three Viral Diseases do you need to learn about?
Measles
HIV/AIDS
Tobacco mosaic virus (TMV)
(there are heaps of diseased cause by these, but you need to know about these ones).
What is Measles?
It is a viral disease.
How do measles spread?
by droplets from an infected person’s sneeze or cough.
What symptoms do you get when measles develop?
a red skin rash,
fever (high temperature)
Is measles a serious virus?
yes, very serious, or even fatal, if there are complications
for example, measles can sometimes lead to pneumonia (a lung infection), or inflammation of the brain (encephalitis).
Can you get vacinated against measles?
yes, most people are vacinnated against measles when they’re young.
What is HIV?
HIV (Human Immunodeficiency Virus) is a virus. The virus atacks the immune cells.
How do HIV (Human Immunodeficiency Virus) spread?
it is spread by sexual contact, or by exchangng bodily fulids, such as blood.
(this can happen when people share needles when taking drugs).
What are the symptoms of HIV (Human immunodeficiency Virus)?
initially it causes flu-like symptoms for a few weeks. Usually the person doesn’t then experience any symptoms for several years.
How can HIV (Human immunodeficiency Virus), be treated?
it can be controlled with antiretroviral drugs. These stop the virus replicating in the body.
Is HIV a serious virus and why?
Yes, if the body’s immune system is badly damaged, it can’t cope with other infections or cancers. At this stage, the virus is known as late stage HIV infection or AIDS (Acquired Immunodeficiency Syndrome).
What is Tobacco Mosaic Virus (TMV)?
a virus that affects many species of plants.
e.g. tomotoes.
How do Tobacco Mosaic Virus (TMV) spread?
it causes a mosaic pattern on the leaves of the plants - parts of the leaves become discoloured.
What happens to the plants leaves, if Tobacco Mosaic Virus (TMV) discolours the plants leaves?
The discolouration means the plant can’t carry out photosynthesis as well, so the virus affects growth.
Why is Photosynthesis important for plant growth?
because it produces glucose (see page 50).
What is Rose Black Spot?
it is a fungus that causes purple or black spots to develop on the leaves of rose plants.
What happens to the leaves of roses if a Rose plant has Rose Black Spot?
The leaves can turn yellow and drop off.
What happens if the Rose leaves drop off?
this means that less photosynthesis can happen, so the plant doesn’t grow very well.
How do Rose Black Spot fungus spread?
it spreads through the environment in water or by the wind.
How can Gardeners treat Rose Black Spot?
Gardeners can treat the disease using fungicides and by stripping the plant of its affected leaves. The leaves then need to be destroyed so that the fungus can’t spread to other rose plants.
What is fungicides?
a chemical that destroys fungus.
What is Malaria?
it is caused by a Protist (protists are singled-celled eukaryotes)
Part of the Malarial Protist’s life cycle takes place inside the mosquito.
How is Marlaria spread?
part of the malarial protist’s life cycle takes place inside the mosquito. The mosquitoes are vectors (an insect that carries the protist), they pick up the malarial protist when they feed on an infected animals. Everytime the mosquito feeds on another animal, it infects it by inserting the protist into the animal’s blood vessels.
Is Malaria serious?
Yes, it causes repeating episodes of fever. It can be fatal.
How can Malaria be reduced?
by stopping the mosquitoes from breeding,
How can people protect themselves from mosquitoes?
by using insecticides and mosquito nets.
What symptom of measles is shown on the skin?
a red skin rash. (1 mark)
How can Rose Black Spot be treated so that it doesn’t spread to other plants?
Using a fungicide (1 mark), and by stripping the plants of the affected leaves and destroying them (1 mark).
