Communicable Disease Biology

Question 1

What are communicable diseases?

Answer 1

Diseases caused by pathogens that can be transmitted from one individual to another

Question 2

Define ‘pathogens’.

Answer 2

Microorganisms that cause diseases

Question 3

State the four types of pathogens.

Answer 3

Bacteria, viruses, protists, fungi

Question 4

How do bacteria make you ill?

Answer 4

Reproduce rapidly and damage cells + Produce toxins

Question 5

How do viruses make you ill?

Answer 5

Produce inside body cells, causing damage

Question 6

How can pathogens be spread?

Answer 6

By air/droplet infection, direct contact, water

Question 7

state one method to prevent the spread of disease.

Answer 7

Isolation; Maintain good hygiene; Destroy vectors; Vaccination

Question 8

How can bacterial diseases be treated?

Answer 8

Antibiotics

Question 9

Name a fungal disease in humans.

Answer 9

Athlete’s foot

Question 10

Which pathogen causes rose black spot?

Answer 10

Fungi

Question 11

Which pathogen causes malaria.

Answer 11

Protists

Question 12

How is malaria spread?

Answer 12

By female Anopheles mosquitoes

Question 13

How does malaria affect the body?

Answer 13

Damages blood and liver cells

Question 14

How can the spread of malaria be stopped?

Answer 14

Use mosquito nets; Use insecticides; Remove standing water; Take antimalarial drugs

Question 15

What are the non specific defense mechanisms of the body against pathogens (4)

Answer 15

Skin
Nose
Trachea and bronchi
Stomach

Question 16

How does the skin protect against pathogens(3)

Answer 16

Acts as a barrier
Produces antimicrobial secretions
Covered with microorganisms that also act as a barrier

Question 17

How does the nose protect against pathogens

Answer 17

Full of hairs that produce mucus that traps particles in air that may carry pathogens

Question 18

How does the trachea and bronchi protect against pathogens

Answer 18

Secrete mucus that traps pathogens, cilia transport mucus to stomach

Question 19

How does the stomach protect against pathogens

Answer 19

Contains acid which kill pathogens that are transported to it in food or in mucus

Question 20

What is the role of the immune system

Answer 20

To destroy pathogens that make it past the first line of defence

Question 21

What are the types of white blood cells

Answer 21

Phagocytes
Lymphocytes

Question 22

How do lymphocytes protect against disease

Answer 22

Antibody production - Target particular pathogen’s antigen, bind to them and destroy them. A unique antibody is used for each antigen
Antitoxin production - Bind to toxins produced by pathogens and stop them from causing damage

Question 23

What is a vaccine

Answer 23

dead or inactive pathogenic material used in vaccination to develop immunity to a disease in a healthy person

Question 24

Describe the process involved in vaccination (4)

Answer 24

Small amounts of dead or inactive pathogen are injected into body
Antigens in vaccine stimulate white blood cells into making antibodies
Blueprints for those antibodies used for that pathogen are stored in memory cells
In future infections antibody can be quickly produced to quell infection

Question 25

What are antibiotics

Answer 25

Drugs used to treat bacterial diseases

Question 26

How do antibiotics work

Answer 26

Destroy bacterial cells without damaging anything else

Question 27

Why can’t antibiotics treat viral diseases

Answer 27

Because antibiotics only destroy bacteria

Question 28

Why is it difficult to treat viral diseases

Answer 28

Because the viruses hide inside the patients cells, meaning the patients cells must be damaged to damage the virus

Question 29

What are painkillers

Answer 29

Drugs that treat the symptoms of a disease to increase quality of life but don’t actually treat the disease

Question 30

State the order of drug trialing (5)

Answer 30

Scientists user computer models to identify molecules to target
Drug discovered, usually using computer models
Preclinical trials (Cell colonies, tissues, Live animals)
Clinical trials (1 - small healthy group(low dosage), 2 - large healthy group(medium dosage), 3 small unhealthy(low dosage)
Licensing

Question 31

What is a double blind trial

Answer 31

One in which neither the patient nor the conductor know who is given the real drug and who is given the placebo in an attempt to eliminate observer bias

Question 32

communicable disease

Answer 32

disease that is transmitted from one individual to another by pathogens

Question 33

non communicable disease

Answer 33

disease that is not transmitted from person to person i.e cancer, defects, radiation, natural causes