B5 - Disease

Question 1

What are the main symptoms of measles?

Answer 1

Fever and a red skin rash

Question 2

How is measles spread?

Answer 2

Spread by inhalation of droplets from coughs or sneezes and is very infectuous

Question 3

How is measles treated?

Answer 3

There is no treatment for measles so if someone becomes infected then they need to be isolated to stop the spread of the virus

Question 4

Why is measles now rare in the UK?

Answer 4

Measles is now rare in the UK as a result of improved living conditions and a vaccination programme for young children

Question 5

With HIV, what are the symptoms to begin with?

Answer 5

The virus only causes a mild flu-like illness to begin with so many don’t realise they have it

Question 6

How does the HIV virus cause damage? How does it lead to Aids?

Answer 6

It attacks the immune cells and after after the initial mild illness, it remains hidden inside the immune system, sometimes for years until the immune system is so badly damaged that it can no longer deal with certain cancers or infections. At this point, the patient has developed Aids.

Question 7

How is HIV spread?

Answer 7

HIV is spread by direct sexual contact and the body exchanges body fluids, such as blood which occurs when drug users share needles or unscreened blood is used for transfusions. It could also be passed on by breastfeeding

Question 8

How is HIV treated?

Answer 8

There is no cure for HIV/AIDS, however the spread of the disease can by prevented by using condoms, screening blood for transfusions, not sharing needles and HIV-positive mothers bottle-feeding children

Question 9

What does TMV stand for?

Answer 9

Tobacco Mosaic Virus

Question 10

Which plants are affected by TMV?

Answer 10

It affects around 150 species of plant, including tomatoes and tobacco plants

Question 11

Why is TMV called a ‘mosaic’ virus?

Answer 11

It is called a ‘mosaic’ virus as it causes a distinctive mosaic pattern of discoloration on the leaves as the virus destroys the cells, affecting the growth of the plant.

Question 12

How is TMV spread?

Answer 12

It is spread by contact between diseased plant material and healthy plants and insects can act as vectors

Question 13

How is TMV treated?

Answer 13

There is no treatment and farmers now grow TMV-resistant strains of many crop plants. Good field hygiene and good pest control can help to prevent the spread of TMV

Question 14

What are Salmonella and where are they found?

Answer 14

Salmonella are bacteria that live in the guts of many different animals, found on raw meat, poultry, eggs and egg products such as mayonnaise

Question 15

What are the symptoms of salmonella infection?

Answer 15

The symptoms of a salmonella infection develop within 8-72 hours of eating infected food, including fever, abdomial cramps, vomiting and diarrhoea, caused by the bacteria and toxins they secrete

Question 16

How can salmonella infection be prevented?

Answer 16

In the UK, poultry are vaccinated against Salmonella to control the spread of the disease.

Question 17

What is Gonorrhoea?

Answer 17

Gonorrhoea is an STI (Sexually Transmitted Infection)

Question 18

How is Gonorrhoea spread?

Answer 18

It is spread by unprotected sexual contact with an infected person.

Question 19

What are the symptoms of Gonorrhoea infection (short-term and long-term)?

Answer 19

Short term - thick yellow or green discharge from vagina or penis and pain on urination

Long term - pelvic pain, infertility and ectopic pregnancies

Question 20

How is Gonorrhoea treated?

Answer 20

Gonorrhoea is bacterial so can be treated with antibiotics. Originally, it was easily cured using penicillin but now many antibiotic-strains of gonorrhoea have evolved so it is increasingly difficult to treat. The spread of gonorrhoea can also be spread by using a barrier method of contraception such as a condom and by reducing the number of sexual partners.

Question 21

Is Rose Black Spot a fungal or protist disease?

Answer 21

Fungal disease

Question 22

Is Malaria a fungal or protist disease?

Answer 22

Protist disease

Question 23

What are the symptoms of rose black spot infection?

Answer 23

Causes purple or black spots to develop on rose leaves. Leaves often turn yellow and drop early.

Question 24

How is Rose Black Spot spread?

Answer 24

Spores of the fungus are spread in the environment, carried by the wind. They are then spread over the plant after it in drips of water that splash from one leaf to another.

Question 25

How can the spread of Rose Black Spot prevented?

Answer 25

Gardeners try to prevent the spread by removing and burning affected leaves and stems. Chemical fungicides can also help to treat the disease and prevent its spreading.

Question 26

The protist that causes malaria is referred to as a ‘parasite’ - what does this mean?

Answer 26

They live and feed on other organisms

Question 27

How are mosquitoes involved in the spread of the malarial protist parasite?

Answer 27

Mosquitoes act as a vector of the disease. The female mosquito needs two meals of human blood before she can lay her eggs, which is when the protists are passed into the human bloodstream.

Question 28

What are the symptoms of malaria?

Answer 28

Malaria causes recurrent episodes of fever and shaking when the protists burst out of the blood cells and it can be fatal.

Question 29

Give four ways the spread of malaria can be controlled:

Answer 29

1.) Using insecticide-impregnated insect nests
2.) Using insecticides to kill mosquitoes
3.) Preventing the vectors from breeding by removing standing water and spraying water with insecticides to kill larvae
4.) Could take antimalarial drugs, kill paradises in the blood