Health and Nutrition

Question 1

What are the nutrients needed for a healthy diet?

Answer 1

Carbohydrates
Lipids 
Proteins 
Vitamins 
Minerals
Water 
Fibre

Question 2

What are the uses of these nutrients inside the body?

Answer 2

Carbohydrates- used for energy in respiration.
Lipids- a store of energy, protection for organs, insulation from heat loss.
Proteins- used for growth and repair.
Vitamins- needed to keep you healthy.
Minerals- needed to keep you healthy.
Water- needed in all cells and body fluids.
Fibre- to aid in digestion by providing bulk to keep food moving through the digestive system.

Question 3

Give examples of foods high in each of the particular nutrients:

Answer 3

Carbohydrates- bread, pasta, sugary foods (fruits and sugar)
Lipids- fats and oil like butter, margarine etc.
Proteins- meat, fish, eggs, beans.
Vitamins - (different foods have different vitamins) fruit, vegetables, meat.
Minerals- milk, cheese, green vegetable and fruit.
Water
Fibre- cereals, fruit, nuts and vegetables.

Question 4

What is a balanced diet?

Answer 4

A diet which contains all the different types of food groups, eaten in the right amounts.

Question 5

Name the chemical used to test for starch?

Answer 5

Iodine solution

Question 6

Name the chemical/substances used to test for lipids:

Answer 6

Ethanol and water

Question 7

Name the substance used to test for sugar:

Answer 7

Benedicts solution - pale blue

Question 8

Name the substances used to test for protein:

Answer 8

Biuret solution - made from copper sulfate solution and sodium hydroxide.

Question 9

What colour does iodine solution turn in the presence of starch?

Answer 9

It turns dark blue/black

Question 10

What does a positive for fats look like?

Answer 10

Two separated layers in the test tube with the top layer being cloudy white.

Question 11

What does a positive test for sugar look like?

Answer 11

Solution starts blue then turns:
Green for a low level of sugar.
Orange for a medium level of sugar.
Brick red for a high level of sugar.

Question 12

What does a positive test for protein look like?

Answer 12

Begins with biuret solution being blue then turns purple in the presence of protein.

Question 13

Describe how to prepare a food solution for solid food:

Answer 13

1. Crush sample of solid food in pestle and mortar.
2. Then add distilled water to crushed food,
3. Mix
4. Then filter solution to remove all solid material, using funnel and filter paper.

Question 14

What is an unbalanced diet?

Answer 14

A diet where one of more of the food groups is lacking or eaten in the wrong amounts.

Question 15

Why is it unhealthy to be underweight?

Answer 15

It is unhealthy to be underweight as this can lead to:

• health problems such as a low immune system.
• a lack of energy and being too tired.
• more likely to suffer from lack of vitamins and minerals.

Question 16

Why is it unhealthy to be overweight?

Answer 16

More likely to suffer from:

• Heart disease
• Stroke
• Diabetes
• Some cancers

Question 17

What can cause a person to be overweight?

Answer 17

If a person eats too much fatty foods or takes in more energy than they use then their body stores the excess energy as fat.

Question 18

What is a deficiency disease?

Answer 18

A deficiency disease is when someone is lacking in one or more vitamins or minerals and as a result suffers from health problems because of it.

Question 19

What factors can affect the amount of energy someone needs?

Answer 19

A person’s energy requirements depend on:

• Age (as it can affect growth rate)
• Body size
• How active they are (more exercise requires more energy)

Question 20

What is the digestion?

Answer 20

Digestion is when large molecules of food are broken down into smaller molecules in order to be absorbed in to the bloodstream by the body.

Question 21

Name the main parts of the digestive system:

Answer 21

• Mouth
• Gullet/oesophagus
• Stomach
• Small intestine
• Large intestine
• Rectum
• Anus

Question 22

Describe the functions of the main parts of the digestive system (part 1):

Answer 22

Mouth – food is chewed and mixed with saliva.
Gullet/oesophagus- tube which connects the mouth to the stomach.
Stomach- churns/mixes chewed food with digestive juices and acid.
Small intestine- where the majority of nutrients are absorbed in to the blood stream.
Large intestine- where the excess water is absorbed back in to our bodies

Question 23

Describe the functions of the main parts of the digestive system (part 2):

Answer 23

Rectum - solid waste (faeces) is stored here before being expelled from the body.
Anus - Muscular ring which the faeces passes through to get out the body.

Question 24

Name the substance produced by the stomach to help digestion:

Answer 24

• Enzymes called protease to help digest protein.
• Produces Hydrochloric acid (HCl) which kills microorganisms that might make us ill.
• The acid also produces the correct pH in the stomach for the protease enzymes to function.

Question 25

Give ways in which the small intestine is adapted to absorb nutrients from digestion:

Answer 25

The small intestine is adapted:

• Thin walls to allow it to absorb nutrients quickly.
• Covered in tiny structures called villi which increase the surface area of the intestines.
• Good supply of blood to carry away absorbed food molecules.

Question 26

What is a catalyst?

Answer 26

A catalyst is a substance that can speed up chemical reactions without being used up itself.

Question 27

What are enzymes?

Answer 27

These are special proteins; in digestion they can break large molecules into smaller ones. They are also known as biological catalysts.

Question 28

What enzyme breaks down carbohydrates?

Answer 28

Carbohydrase enzymes.

Question 29

What are carbohydrates broken down into?

Answer 29

Carbohydrates like starch are digested in to sugars like glucose.

Question 30

What enzyme breaks down proteins?

Answer 30

Protease enzymes.

Question 31

What are proteins broken down into?

Answer 31

Proteins are digested into amino acids.

Question 32

What enzyme breaks down lipids?

Answer 32

Lipase enzymes.

Question 33

What are lipids broken down into?

Answer 33

Lipids are digested in to fatty acid and glycerol molecules.

Question 34

What role do bacteria play in digestion?

Answer 34

The bacteria digest fibre in your diet and produce vitamins that are absorbed by the body.

Question 35

What do we call foods that contain good bacteria?

Answer 35

Probiotic foods.

Question 36

Give example of probiotic foods:

Answer 36

Live yoghurt, soft cheese, breakfast drinks like yakult and actimel.

Question 37

What does Bile do?

Answer 37

Bile helps to break down large droplets of fat in to smaller ones, making it easier for the lipase enzyme to digest them.

Question 38

Where is bile produced?

Answer 38

Bile is produced in the liver.