Nutrition (Human Diet)

Question 1

What are all the components you must have in the right proportions for a balanced diet?

Answer 1

• Carbohydrates
• Proteins
• Lipids
• Minerals
• Vitamins
• Water
• Dietary Fibre

Question 2

What are the functions of carbohydrates for humans?

Answer 2

They are a source of energy

Question 3

What are the functions of lipids for humans?

Answer 3

• Energy storage as fat contains much energy
• They are necessary for the production of cell membranes
• Insulation

Question 4

What are the functions of proteins for humans?

Answer 4

• Growth and repair
• Enzymes, DNA and hormones

Question 5

What are the functions of dietary fibre for humans?

Answer 5

Provides an indigestible bulk for the intenstine to push food through it, preventing constipation

Question 6

What are the functions of water for humans?

Answer 6

• It is needed for chemical reactions to take place in the body
• Temperature regulation
• Keeping the blood water levels high enough so cells do not become flaccid and the blood is not too thick to be efficiently pumped around

Question 7

What are sources of carbohydrates for humans?

Answer 7

Bread, pasta, rice, potatoes

Question 8

What are sources of proteins for humans?

Answer 8

Meat, Fish, Eggs, Nuts, Beans

Question 9

What are sources of lipids for humans?

Answer 9

Butter, Oil, Nuts

Question 10

What are sources of dietary fibre for humans?

Answer 10

Vegetables, Wholegrains

Question 11

What are sources of water for humans?

Answer 11

Water, Milk, Juice, Fruits & Vegetables

Question 12

What are the functions of calcium for humans?

Answer 12

Needed for strong bones and teeth

Defiency can cause rickets

Question 13

What are the functions of iron for humans?

Answer 13

Needed for the production of haemoglobin in red blood cells to transport oxygen around the body

Deficiency can cause anemia

Question 14

What are the functions of vitamin A for humans?

Answer 14

It is needed for night vision as it is a component of the pigment in the retina

Question 15

What are the functions of vitamin D for humans?

Answer 15

Helps the body absorb calcium so it is needed for strong bones and teeth

Deficieny can cause rickets

Question 16

What are the functions of vitamin C for humans?

Answer 16

• It is needed for the production of collagen protein which is necessary for gums, hair, skin and bones
• It is also needed for the immune system

Question 17

What are the sources of calcium for humans?

Answer 17

Milk, Cheese, Eggs

Question 18

What are the sources of iron for humans?

Answer 18

Red meat, liver, leafy green vegetables

Question 19

What are the sources of vitamin A for humans?

Answer 19

Leafy green vegetables, eggs, carrots

Question 20

What are the sources of vitamin C for humans?

Answer 20

Citrus fruits, green vegetables, strawberries

Question 21

What are the sources of vitamin D for humans?

Answer 21

Sunlight, Eggs, Fish

Question 22

How does age affect energy and nutritional requirements?

Answer 22

• From birth, energy requirement slowly increases and peaks at adolescence where growth is the highest and the individuals are already fairly large
• They will also need more protein at this stage due to their growth
• As an adult gets older, they require less energy and protein as muscle mass and metabolic rate steadily declines

Question 23

How do activity levels affect energy and nutritional requirements?

Answer 23

• The more active someone is, the more energy they will need as they are respiring more
• They will need more protein for their muscles to recover

Question 24

How does pregnancy affect energy and nutritional requirements?

Answer 24

• Energy requirements will increase to support the growth of the foetus and the larger weight of the mother
• More calcium, iron and protein are needed to support the growth of the baby

Question 25

How does breastfeeding affect energy and nutritional requirements?

Answer 25

More energy and calcium are needed to support the production of breast milk

Question 26

How does a persons sex affect their energy requirements?

Answer 26

Males on average need more than females, as males are heavier and have more muscle

Question 27

Outline an experiment to test for the energy content of a food sample

Answer 27

• Record the starting temperature of a specific volume of water
• Weigh the mass of the food sample
• Completely burn the food by lighting it with a bunsen burner underneath the tube
• Record the final temperature of the water
• Repeat with different food samples
• A larger increase in temperature per mass of food indicates a larger energy content in the food

Question 28

How do you work out the amount of energy in a food sample per gram?

Answer 28

Energy transferred = 4.2 x Temp. Increase x Mass of water/Mass of food sample

Question 29

Why might the result you get for the energy of the food sample be less than it really is?

Answer 29

• Heat convects around the test tube
• The test tube conducts some of the heat
• Heat radiates out of the water
• The burning of the food may have been incomplete