b5 communicable diseases

Question 1

What is health?

Answer 1

A state of physical mental, and social well-being, not just the absence of disease.

Question 2

What are communicable diseases?

Answer 2

Diseases caused by pathogens that can spread between organisms (e.g.

Question 3

What are non-communicable diseases?

Answer 3

Diseases that cannot spread between organisms (e.g.

Question 4

How can diseases interact?

Answer 4

One disease can increase the risk of another (e.g.

Question 5

What are pathogens?

Answer 5

Microorganisms that cause infectious diseases (e.g.

Question 6

How do bacteria cause disease?

Answer 6

They produce toxins that damage cells and tissues.

Question 7

How do viruses cause disease?

Answer 7

They invade and replicate inside cells

Question 8

What are examples of diseases caused by bacteria?

Answer 8

Salmonella (food poisoning)

Question 9

What are examples of diseases caused by viruses?

Answer 9

HIV (AIDS)

Question 10

What are examples of diseases caused by fungi?

Answer 10

Athlete’s foot

Question 11

What are examples of diseases caused by protists?

Answer 11

Malaria (spread by mosquitoes).

Question 12

How are pathogens spread?

Answer 12

Through air

Question 13

Why are cultures of microorganisms grown in labs?

Answer 13

To study pathogens and test antibiotics.

Question 14

What is a culture medium?

Answer 14

A substance with nutrients for microorganisms to grow (e.g.

Question 15

What is aseptic technique?

Answer 15

A method to prevent contamination when growing microorganisms (e.g.

Question 16

Why are cultures incubated at 25°C in schools?

Answer 16

To reduce the risk of growing harmful pathogens.

Question 17

What is the purpose of sterilising inoculating loops?

Answer 17

To kill microorganisms and prevent contamination.

Question 18

What is the aim of the microbiology practical?

Answer 18

To test the effect of antibiotics or antiseptics on bacterial growth.

Question 19

How do you set up the practical?

Answer 19

1) Sterilise equipment. 2) Spread bacteria on agar. 3) Add antibiotic discs. 4) Incubate at 25°C.

Question 20

What do clear areas around antibiotic discs indicate?

Answer 20

Bacteria have been killed

Question 21

Why must petri dishes be sealed with tape?

Answer 21

To prevent contamination but allow oxygen in.

Question 22

What are examples of plant diseases caused by pathogens?

Answer 22

Rose black spot (fungus)

Question 23

What are symptoms of rose black spot?

Answer 23

Purple/black spots on leaves

Question 24

What are symptoms of tobacco mosaic virus?

Answer 24

Mosaic discolouration on leaves

Question 25

How do plants defend themselves against pathogens?

Answer 25

Physical barriers (e.g.

Question 26

What are mechanical defences in plants?

Answer 26

Thorns

Question 27

What are the three main lines of defence in the human body?

Answer 27

1) Physical barriers (e.g.

Question 28

How does the skin protect against pathogens?

Answer 28

Acts as a barrier and produces antimicrobial secretions.

Question 29

How does mucus protect against pathogens?

Answer 29

Traps pathogens in the respiratory and digestive tracts.

Question 30

What is the role of white blood cells?

Answer 30

They engulf pathogens

Question 31

What are antibodies?

Answer 31

Proteins that bind to specific antigens on pathogens

Question 32

What is immunity?

Answer 32

The ability to resist infection

Question 33

What is vaccination?

Answer 33

Introducing a harmless dose of a pathogen to stimulate immunity.

Question 34

How do antibiotics work?

Answer 34

Kill or inhibit bacteria (but not viruses).

Question 35

Why is antibiotic resistance a problem?

Answer 35

Overuse leads to resistant bacteria

Question 36

What is herd immunity?

Answer 36

When most of a population is immune

Question 37

How does herd immunity work?

Answer 37

Immune people stop the pathogen spreading

Question 38

Why is herd immunity important?

Answer 38

It protects vulnerable people who can’t be vaccinated (e.g.

Question 39

What percentage of the population needs to be immune for herd immunity?

Answer 39

Usually 80-95% for highly infectious diseases like measles.