Proteins

Question 1

What are proteins made up of?

Answer 1

Amino Acids

Question 2

What are the two classifications of protein?

Answer 2

Dispensable

Indispensable

Question 3

What does dispensable mean?

Answer 3

Synthesised by the body
Non - essential
Convert one amino acid into another - transamination

Question 4

What does indispensable mean?

Answer 4

Not synthesised by the body
Are essential
Must be provided by the diet

Question 5

How many indispensable amino acids are there?

Answer 5

8 for adults

9 for children (Histidine for growth)

Question 6

Why might other amino acids not be synthesised by the body

Answer 6

During illness or injury some amino acids may not be synthesised and have to be provided by the diet.

Question 7

What is biological value?

Answer 7

The percentage of protein that is absorbed by the body and used for different functions such as growth

Question 8

Name 3 things the quality of protein food might be judged by:

Answer 8

Protein content
Amount of indispensable/ essential amino acids present
The degree of which protein is digested and absorbed

Question 9

What are high biological foods?

Answer 9

Contains all the essential/ indispensable amino acids

Question 10

Where are HBV proteins found

Answer 10

In animal products ( meat, fish, eggs)

Question 11

What is the only plant source that is an HBV

Answer 11

Soya products

Question 12

What are low biological foods?

Answer 12

Contains some but not all the essential/ indispensable amino acids.

Question 13

Where are LBV proteins found?

Answer 13

In plant sources ( rice, peas, lentils)

Question 14

What is the only animal source of an LBV?

Answer 14

Gelatine

Question 15

What is the limiting amino acid?

Answer 15

Lysine

Question 16

What is homeostasis?

Answer 16

This is maintaining a constant internal environment

Question 17

How are hormones a function of protein?

Answer 17

Needed for the production of hormones
They regulate metabolic processes, blood glucose levels and digestion.
Vasopressin is a hormone involved in homeostasis

Question 18

How is acid base balance a function of protein?

Answer 18

Proteins are very sensitive to pH levels

If they are outside a suitable level the protein will become denatured, lose its ability to function and death may occur

Question 19

Why is fluid base balance an important part of homeostasis?

Answer 19

Prevent loss of body fluids, plasma exerts an osmotic effect to hold fluid within circulation. Oedema can occur

Question 20

Why is immunity an important part of homeostasis?

Answer 20

low immune system = more susceptible to infection.

Children who suffer protein energy malnutrition are more susceptible to infection

Question 21

Explain the function transport:

Answer 21

Substances attach themselves to proteins
Are carried around the body
E.g. haemoglobin being transported to muscles
Transportation across a cell membrane

Question 22

Explain the function blood clotting:

Answer 22

Proteins found in plasma e.g. Fibrinogen increase blood clotting factors and reduce prolonged bleeding

Question 23

Explain the function body structure:

Answer 23

Protein is needed for growth, repair and maintenance.
Protein requirements increase during times of growth
Protein is synthesised and replaced throughout life

Question 24

Why must proteins be replaced?

Answer 24

Proteins in tissues must be replaced by amino acids provided by the diet because they are constantly being broken down

Question 25

Explain the function hair, bones and nails:

Answer 25

They are vital in the formation and structure of all cell membranes

Question 26

What are novel sources of protein?

Answer 26

Mimic the sensory properties of meat (texture, smell, look) | Mostly suitable for vegetarians

Question 27

What are the two main novel proteins?

Answer 27

Processed plant foods ( soya products) | Produced from micro-organisms (Quorn)

Question 28

Some nutritional value of fish, meat and eggs:

Answer 28

``` HBV proteins Omega 3 in fish Fat soluble vitamins (A and D) Haem Iron Zinc, phosphorus, iodine ```

Question 29

Dairy products nutritional value:

Answer 29

Calcium Phosphorus Vit A (retinol), D, B12

Question 30

Plant sources nutritional value:

Answer 30

``` Non-haem iron low in cholesterol low in saturated fat low in calories Dietary Fibre Antioxidants Isoflavones ```

Question 31

Nutritional value of soya:

Answer 31

``` HBV protein Iron Calcium Antioxidants low GI Selenium and potassium ```

Question 32

The nutritional value of Quorn:

Answer 32

``` HBV proteins Low sodium Low iron Low in vit A, B Soluble and Insoluble fibre Calcium Carbs ```

Question 33

Why are isoflavones important?

Answer 33

They are thought to reduce risk of cancer and CVD

Question 34

What is nitrogen balance?

Answer 34

This is the difference between nitrogen input and nitrogen output. The overall indicator of protein metabolism in the body