1-Keeping Healthy

Question 0

What are the different foods our body needs?

Answer 0

Carbohydrates, fats, proteins, fibre, vitamins, minerals and water.

Question 1

What is a healthy diet?

Answer 1

A diet that contains the correct balance of different foods our body needs and the right amount if energy.

Question 2

What are carbohydrates, proteins and fats used for?

Answer 2

To release energy and build up cells.

Question 3

What are minerals and vitamins used for?

Answer 3

In small amounts for healthy functioning of the body.

Question 4

When is a person malnourished?

Answer 4

When their diet isn’t balanced.

Question 5

What can a poor diet lead to?

Answer 5

Being overweight/underweight.

Deficiency diseases and conditions like Type 2 diabetes.

Question 6

What does exercise do?

Answer 6

Increase the amount of energy expended by the body.

Question 7

When will a person lose mass?

Answer 7

When the energy content of food taken in is less than energy expended by the body.

Question 8

Who is healthier: someone who does exercise or someone who does little exercise?

Answer 8

Someone who does exercise.

Question 9

What is the metabolic rate?

Answer 9

The rate at which all chemical reactions in the cells of the body are carried out.

Question 10

How does your metabolic rate vary?

Answer 10

Amount of exercise you do-increases with more exercise and stays high for a while after.
Proportion of fat to muscle in your body.
Inherited factors.

Question 11

Where is cholesterol made?

Answer 11

In the liver.

Question 12

How is the amount of cholesterol produced affected?

Answer 12

Diet and inherited factors.

Question 13

What are the pros of a low-carbohydrate diet?

Answer 13

• Lose weight very quickly in short term
• Easy way to lose weight
• Can still eat many things that would be cut out of a normal slimmer’s diet

Question 14

What are the cons of a low-carbohydrate diet?

Answer 14

Drastic changes can have a negative effect on body.
Exercise may not encouraged but needed to be healthy, especially when eating so much fat.
Body needs balanced diet to be healthy.
Body misses out on essential nutrients found in fruit, veg and grains.
Long term intake of protein put strain on kidneys.
Protein stores get used up as well as fat.
Lack of energy.

Question 15

What are pathogens?

Answer 15

Microorganisms that cause infectious diseases.

Question 16

What are the two main types of pathogen that affect health?

Answer 16

Bacteria and viruses.

Question 17

What are the characteristics of bacteria?

Answer 17

Very small.
Reproduce very quickly.
Can produce toxins that make us feel ill.
Responsible for illnesses like tetanus, cholera and tuberculosis.

Question 18

What are the characteristics of viruses?

Answer 18

Even smaller than bacteria.
Reproduce very quickly inside living cells, which are damaged.
Can produce toxins which make us feel ill.
Responsible for illnesses like colds, flu, measles and polio.

Question 19

How do white blood cells help defend against pathogens?

Answer 19

Ingesting pathogens.
Producing antitoxins to neutralise toxins.
Producing antibodies to destroy particular pathogens, leading to immunity.

Question 20

How are some symptoms alleviated?

Answer 20

Using painkillers, eg. Aspirin, but they don’t kill pathogens.

Question 21

What are used to kill pathogens inside the body?

Answer 21

Antibiotics, eg. Penicillin.

Question 22

Why can’t antibiotics be used to kill viruses?

Answer 22

They live and reproduce inside cells and it’s difficult to produce drugs that destroy viruses without damaging the body’s tissues.

Question 23

Why has MRSA developed?

Answer 23

Through the overuse and inappropriate use of antibiotics.

Question 24

How does resistance happen?

Answer 24

When bacteria mutate to produce new resistant strains.
Some bacteria may have a natural resistance and when the antibiotic is used the non-resistant strain is killed. This leaves the resistant strain which reproduce and so the population increases.

Question 25

How do we slow down the rate of development of resistant strains?

Answer 25

Antibiotics aren’t used to treat non-serious infections eg. Sore throats.

Question 26

How can a person acquire immunity from a disease?

Answer 26

By being vaccinated.

Question 27

How are you vaccinated?

Answer 27

1. An inactive/dead pathogen is injected into the body.
2. White blood cells produce antibodies to destroy the pathogen.
3. The body has now acquired immunity as the white blood cells are sensitised to it and will respond quickly to any future infection.

Question 28

How can you greatly reduce the spread of a pathogen?

Answer 28

By vaccinating a large proportion if the population.

Question 29

How can microorganisms be grown?

Answer 29

In a culture medium containing nutrients it may need.

Question 30

What nutrients may a culture medium need for the microorganisms?

Answer 30

Carbohydrates-energy source.
Mineral ions.
Vitamins.
Proteins.

Question 31

What is most commonly used as the growth medium?

Answer 31

Agar.

Question 32

Why are uncontaminated cultures of microorganisms needed?

Answer 32

For investigating the action of antibiotics.

Question 33

Why do the cultures of microorganisms need to be uncontaminated?

Answer 33

So unwanted microorganisms don’t produce undesirable substances that can be harmful.

Question 34

How do you prepare an uncontaminated culture of microorganisms?

Answer 34

1. Sterilisation of Petri dishes & culture medium:
   Both are sterilised using an autoclave which exposes them to high temperature and pressure to kill microorganisms.
2. Sterilisation of inoculating loops:
   Usually made of nichrome wire, should be heated to a red heat in a Bunsen flame and left to cool for five seconds. They can them be used safely to transfer microorganisms to the culture medium.
3. Sealing Petri dish:
   After agar has been poured in, it should be sealed with tape and labelled on the base. Should be stored so that condensation forms in the lid.

Question 35

Why does the Petri dish have to be sealed with tape?

Answer 35

To stop microorganisms in the air from entering.

Question 36

At what temperature should cultures be incubated in schools/colleges and why?

Answer 36

25 degrees Celsius. To prevent growth of pathogens that grow at body temperature and could be harmful to humans.

Question 37

At what temperatures should cultures be incubated in industry and why?

Answer 37

High temperatures for more rapid growth.

Question 38

What are the pros of the MMR vaccine?

Answer 38

• Protects children against 3 potentially fatal diseases
• Widespread use prevents epidemics of all the diseases
• Triple vaccine means children only need 1 injection

Question 39

What are the cons of the MMR vaccine?

Answer 39

• Smaller studies suggests link between MMR vaccine and autism
• Some larger studies don’t rule out that MMR may trigger autism in a small number of children

Question 40

What regulations are put in place in hospitals to reduce the chance of infections spreading?

Answer 40

• All staff must wash hands before & after contact with each patient
• All patients must wash hands
• All surgical instruments must be sterilised before use
• Hospital wards must be cleaned regularly with antibacterial cleaner
• Doctors & surgeons must wear disposable face masks, gowns & gloves
• All spillages of body fluids must be cleaned up immediately
• All patients with infectious diseases must be isolated to prevent spreading

Question 41

What are problems facing scientists researching prevention and cures?

Answer 41

1. Some strains of bacteria have developed resistance so more antibiotics need to be developed
2. Some viruses mutate rapidly so exiting vaccines are no longer effective. A vaccine that was effective one year may not be effective the next.
   Scientists always new vaccines for new strains.