Communicable diseases Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is a communicable disease?

A

A disease caused by a pathogen which can be passed between animals or plants such as the flu.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is a pathogen?

A

A disease-causing microorganism such as bacteria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How do bacteria cause disease?

A

Once inside the body, they divide rapidly by binary fission. They kill cells and produce harmful toxins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How do viruses cause disease?

A

They invade and reproduce inside living body cells, leading to cell damage.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Give 3 ways in which pathogens can be spread

A
  • By air: flu, tuberculosis and the common cold are spread by droplet infection.
  • By water: fungal spores in water spread plant diseases.
  • By direct contact: common in plant diseases and sexually transmitted infections.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Give 4 ways in which the spread of pathogens can be reduced

A
  • Hygiene: handwashing, disinfectants, tissues.
  • Reducing contact with infecting individuals: quarantine.
  • Removing vectors: use of pesticides and insecticides, removal of habitats.
  • Vaccination.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why is it especially important to prevent the spread of viral disease?

A

Scientists may have not yet developed cures for many viral diseases.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is measles?

A

Measles is a serious viral disease that can cause blindness and brain damage. The main symptoms are a fever and a red skin rash.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How is measles spread?

A

By air - though the inhalation of droplets from coughs and sneezes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is HIV/AIDS?

A

HIV is a virus which attacks and damages the immune system until it can no longer function properly. AIDS is the condition resulting from a long-term HIV infection. There is no cure or vaccine for HIV/AIDS.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How is HIV spread?

A

Direct sexual contact and the exchange of bodily fluids such as blood and breastmilk.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How can the spread of HIV/AIDS be prevented?

A
  • Use of condoms.
  • Screening of blood for transfusions.
  • Not sharing needles.
  • Bottle-feeding by HIV-positive mothers.
  • Use of antiretroviral drugs to prevent the development of AIDS.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is tobacco mosaic virus?

A

A viral plant disease which causes leaf discolouration when cells are damaged. Affected areas cannot photosynthesise, reducing the crop yield. As there is no treatment, farmer grow TMW-resistant crop strains to avoid infection.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How is tobacco mosaic virus spread?

A

Contact between infected and healthy plants. Insects may act as vectors which transfer the virus between different plants.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is salmonella?

A

A type of bacteria found in raw meat, poultry and eggs. If they enter the body via food poisoning, they can affect natural gut bacteria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the symptoms of salmonella food poisoning?

A
  • Fever.
  • Abdominal cramping.
  • Vomiting.
  • Diarrhoea.

May be fatal in very young or elderly populations due to risk of dehydration.

17
Q

How can the spread of salmonella be limited?

A
  • Vaccinating animals intended for consumption.
  • Keep raw meat away from cooked meat.
  • Disinfect hands and surfaces after contact with raw meat.
  • Thoroughly cook meat.
18
Q

What is gonorrhoea?

A

A sexually transmitted bacterial infection caused by unprotected sex with an infected individual. Early symptoms include yellow/green discharge from genitals and painful urination, although it may be symptomless.

Its spread can be controlled through the use of antibiotics (no longer penicillin as many strains are resistant) and using condoms.

19
Q

What is rose black spot?

A

A fungal disease which causes purple or black spots to develop on rose leaves. It reduces the area of the leaf which is available for photosynthesis and causes leaves to turn yellow and drop prematurely.

20
Q

How is the rose black spot fungus spread?

A

Fungal spores are spread by the wind and in water.

21
Q

How can the rose black spot fungus be treated?

A
  • Using fungicides.

- Destroying infected leaves.

22
Q

What is malaria?

A

Malaria is a disease caused by protist pathogens. The disease is carried from host to host by mosquitoes, and the protists enter the human bloodstream when they feed. Symptoms include fever and shaking, and it may be fatal in some cases.

23
Q

How can the spread of malaria be reduced?

A
  • Using insecticides.
  • using insect nets to avoid bites.
  • Prevent mosquito breeding by removing stagnant water.
  • Antimalarial drugs.
24
Q

How does the skin prevent pathogens from entering the body?

A

Acts as a physical barrier.

  • Scab formation after skin is cut/wounded.
  • Antimicrobial secretions which can kill pathogens.
  • Healthy skin flora compete with pathogens and acts as an additional barrier.
25
Q

How does the respiratory system prevent pathogens from entering the body?

A
  • Nose: has hairs and mucus which trap pathogens.

- Trachea and bronchi: have mucus that traps pathogens. Ciliated cells move mucus to the mouth so it can be swallowed.

26
Q

How does the stomach prevent pathogens?

A

Secretes hydrochloric acid - kills any pathogens present.

27
Q

How does phagocytosis protect us against disease?

A

White blood cells (phagocytes) ingest and destroy pathogens so they cannot infect more cells.

28
Q

How does antibody production protect us against disease?

A

White blood cells produce antibodies which are complementary to a specific antigen on a pathogen. The binding of antibodies to antigens causes pathogens to clump together, making them easier to destroy. In the case of a second infection, the correct antibodies can be produced rapidly, preventing the person getting the same disease again.

29
Q

How does antitoxin production protect us against disease?

A

Antitoxins bind to toxins released by pathogens and neutralise them.

30
Q

What is vaccination?

A

Contains a dead or inactivated form of the pathogen which stimulates the white blood cells to produce complementary antibodies to the pathogen. In the case of a second infection, memory cells can rapidly produce the correct antibodies and prevent illness.

31
Q

What is herd immunity?

A

If a sufficiently high proportion of a population are immune to a disease (especially through vaccination), the spread of this disease will be limited.

32
Q

What are the advantages of vaccinations?

A
  • They have eradicated many deadly diseases such as smallpox.
  • Many epidemics can be prevented by vaccinations.
  • Herd immunity protects those who cannot have vaccinations.
33
Q

What are the disadvantages of vaccinations?

A
  • Not guaranteed to work - might not protect against multiple strains of a pathogen.
  • May be side effects or adverse reactions.