The Functions and Uses of Proteins

Question 1

What are proteins?

Answer 1

Large chains of amino acids.

Question 2

What are four uses of proteins?

Answer 2

• Tissue components
• Hormones
• Antibodies
• Catalysts

Question 3

What are enzymes?

Answer 3

Biological catalysts produced by the body that speed up useful chemical reactions in the body.

Question 4

What is the lock and key model?

Answer 4

A way of presenting how enzymes work. Each one is uniquely shaped to suit a certain substance - if the substance doesn’t fit it won’t react.

Question 5

What happens to enzymes if they become too hot?

Answer 5

They become denatured and deformed so cannot perform their jobs properly.

Question 6

What is the ideal temperature for all enzymes in the human body?

Answer 6

37 degrees

Question 7

What happens if the pH is wrong for an enzyme?

Answer 7

The bonds holding the enzyme together can be damaged which denatures it.

Question 8

What does Amylase break down and into what?

Answer 8

Starch into sugar

Question 9

Where is amylase made?

Answer 9

Salivary glands, pancreas and small intestine.

Question 10

Where does amylase work?

Answer 10

Mouth and small intestine.

Question 11

What does protease break down and into what?

Answer 11

Proteins into amino acids.

Question 12

Where are proteases made?

Answer 12

Stomach, pancreas and small intestine.

Question 13

Where do proteases work?

Answer 13

Stomach and small intestine

Question 14

What does lipase help break down and into what?

Answer 14

Lipids into glycerol and fatty acids.

Question 15

Where are lipases made?

Answer 15

Pancreas and small intestine.

Question 16

Where do lipases work?

Answer 16

Small intestine.

Question 17

What two things does the stomach produce?

Answer 17

Pepsin and hydrochloric acid.

Question 18

Why does the stomach need hydrochloric acid?

Answer 18

1) To kill bacteria

2) To create a pH of 2 at which its enzymes work best

Question 19

Where is bike produced?

Answer 19

The liver

Question 20

Where is bile stored?

Answer 20

The gall bladder?

Question 21

Where is bile used?

Answer 21

The small intestine

Question 22

What is the role of bile?

Answer 22

• It neutralises the stomach acids

* It emulsifies the fat into tiny globules that have a higher surface area to volume ratio so are digested faster

Question 23

What is a common use of enzymes around the home?

Answer 23

In biological detergents which can remove proteins and fats from materials at low temperatures.

Question 24

What are three potential problems with using enzymes in detergents?

Answer 24

• Don’t work all at high temperatures
• May not work in very acidic or alkali tap water
• They can remain on clothes and damage the skin

Question 25

How are enzymes used in baby food?

Answer 25

Some baby food comes “pre digested” using proteases so that they are easier for babies to digest.

Question 26

How are enzymes used to make sugar syrup?

Answer 26

Carbohydrates can turn starch syrup into sugar syrup.

Question 27

How can enzymes be used in slimming foods?

Answer 27

Isomerase can turn glucose syrup into fructose syrup which is sweeter so can be used in smaller quantities.

Question 28

What are four advantages of using enzymes in industry?

Answer 28

• They only catalyse the reaction you want
• They allow reactions to take place at lower temperatures and pressures which saves energy
• Can work for a long time
• They are biodegradable

Question 29

What are three disadvantages of using enzymes in industry?

Answer 29

• They can become denatured very easily
• Very expensive to produce
• Contamination of enzymes can affect the reaction