Chapter 2 - Human Nutrition

Question 1

Name the three main chemical elements that are found in carbohydrates.

Answer 1

Carbon, Oxygen and Hydrogen

Question 2

What types of biological molecules are made up of Fatty Acids and Glycerol?

Answer 2

Lipids

Question 3

What types of biological molecules are made up of Amino Acids?

Answer 3

Protein

Question 4

Describe how you would use Benedict’s solution to test for glucose.

Answer 4

1. prepare a food sample, transfer 5cm3 to a test tube.
2. prepare a water bath, 75 degrees C
3. Add ~10 drops of Benedict’s solution to test tube
4. place test tube in water bath for 5 minutes
5. Note colour change

Question 5

what colour will Benedict’s solution turn if a high glucose is present?

Answer 5

Brick-Red

Question 6

what colour will Benedict’s solution turn if a low Glucose concentration is present?

Answer 6

Green or Yellow

Question 7

What solution could you use to see if there’s starch in a sample?

Answer 7

Iodine solution

Question 8

Describe how you would test for starch with iodine solution

Answer 8

1. Prepare a food sample, transfer 5cm3to a test tube
2. add a few drops of iodine solution and gently shake the tube.
3. Note the colour change

Question 9

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

Answer 9

Brown-Orange to Blue-Black

Question 10

what nutrients does the body get energy from?

Answer 10

Carbohydrates, Lipids and Protein

Question 11

Why does the body need proteins?

Answer 11

Growth and Repair

Question 12

What foods contain proteins?

Answer 12

meat and fish

Question 13

Eric has just been to see his doctor. He has been told that he needs to increase the amount of Vitamin D in his diet. Why might Eric need Vitamin D?

Answer 13

To help the body absorb calcium for strong teeth and bones.

Question 14

explain fully what is meant by the term ‘a balanced diet’

Answer 14

A balanced diet supplies all your essential nutrients in the right proportions.

Question 15

Explain the difference in energy requirement between children and older people.

Answer 15

Children require more energy as they are generally more active.

Question 16

explain the difference in energy requirements between a pregnant woman and a non-pregnant woman

Answer 16

The pregnant woman needs more energy so her baby can develop

Question 17

Describe a simple experiment to measure the amount of energy in a food

Answer 17

1. weigh a small amount of the food, pick it up with a mounted needle
2. add a set volume of water to a boiling tube.
3. measure the temperature of water and light the food sample.
4. immediately, hold the food under the boiling tube until it goes out.
5. Measure the temperature change.

energy in food = Mass of water x Temperature change of water x 4.2

Question 18

give one way you could make the experiment to measure the amount of energy in a food more accurate

Answer 18

Insulate the boiling tube, E.G. with foil. this would minimise heat loss and keep more energy in water.

Question 19

What is the main role of digestive enzymes?

Answer 19

break down big molecules into smaller ones

Question 20

Name the enzyme that converts starch into glucose

Answer 20

amylase converts starch into maltose… maltase converts maltose into glucose

Question 21

what does protease do?

Answer 21

Protease converts proteins into amino acids

Question 22

when lipids are digested, what molecules are they broken down into?

Answer 22

glycerol and fatty acids

Question 23

Where in the body is bile stored?

Answer 23

bile is stored in the gall bladder

Question 24

Where in the body is bile produced?

Answer 24

Bile is produced in the liver

Question 25

Where in the body is bile used?

Answer 25

Bile is used in the stomach

Question 26

what are the two functions of bile?

Answer 26

Bile neutralises stomach acid and emulsifies fats

Question 27

explain how villi help with absorption in the small intestine

Answer 27

Villi increase the surface area of the Small intestine as each villi has their own micro villi.