PROTEINS Flashcards Preview

A Level Food Technology > PROTEINS > Flashcards

Flashcards in PROTEINS Deck (25):
1

What is a protein

Long chain of amino acids

2

What is a protein

Long chain of amino acids

3

How does protein provide energy

Excess protein is converted into glucose which is stored in the liver as glycogen - secondary source of energy

4

What is a protein

Long chain of amino acids

5

How does protein provide energy

Excess protein is converted into glucose which is stored in the liver as glycogen - secondary source of energy

6

Functions of protein

Growth and repair

Secondary source of energy

Maintains body producing enzymes/hormones

7

Sources of protein

Nuts

Pulses

Meat

Eggs

8

Example of protein deficiency

Kwashiorkor
- common in children after weaning

Symptoms
- bloated abdomen
- muscle wasting
-stunted growth

Treatment
- balanced diet (more vitamins and minerals

9

Effects of excess

Excess calories from protein stored as tissue leads to overweight

Strain on organs (kidneys/ liver/ bowel)

Protein foods often high in saturated fat leads to CHD

10

What is protein complementation?

The mixture of LBV proteins as they are incomplete proteins

Two ensure that all essential amino acids are received, two incomplete sources compensate each other's inadequate supply

11

Examples of protein complementation

Beans on toast

Rice and peas

Rice and kidney beans

12

What are essential amino acids

Amino acids that CANT be made by our bodies - must EAT them

13

What are non- essential amino acids

CAN be made by our bodies

14

Chemical structure of protein

Amino/ Acidic
Alkaline Part
Part

H H O
| | ||
N - C - C - OH
| |
H R

R = Variable (changes for each amino acid)

15

What does amphoteric mean?

Amino acids are amphoteric because they contain at least one alkaline group and one acidic group displaying acidic and base properties

16

What are HBVs (high biological value proteins)

Proteins that contain all essential amino acids

17

Examples of HBVs

Animal sources

Meat

Fish

Soya

Dairy

Eggs

18

Chemical structure of protein

Amino/ Acidic
Alkaline Part
Part

H H O
| | ||
N - C - C - OH
| |
H R

R = Variable (changes for each amino acid)

19

What are LBVs (low biological value proteins)

Proteins that don't contain all essential amino acids

20

Examples of LBVs

Plant sources

Peas

Beans

Lentils

Nuts

Grains

Rice

21

Chemical structure of protein

Proteins are large molecules built up of long chains of amino acids

Only 20 of 80 found in foods
8 of 20 are essential

Each amino acid contains at least one acidic group and one amino (alkaline) group

22

What is a peptide link

Chemical bond linking two amino acids along a peptide chain

23

What is a dipeptide link

When two amino acids join together

24

What is a tripeptide bond

3 amino acids

26

What is a Polypeptide chain

Long chain of amino acids joined together

More than 3