2.5 Proteins - their Functions and Uses

Question 1

What are protein molecules made up of?

Answer 1

Long chains of amino acids folded in a certain shape

Question 2

What do proteins act as?

Answer 2

• Structural components of tissues
• Hormones
• Antibodies
• Catalysts

Question 3

What are enzymes?

Answer 3

A biological catalyst that increases the rate of reaction

Question 4

What happens to an enzyme when it’s heated too much?

Answer 4

Its active site is denatured

Question 5

How do enzymes work?

Answer 5

Question 6

Does the optimun pH vary for different enzymes?

Answer 6

Yes

Question 7

What does amylase do?

Answer 7

Starch → Sugars

Question 8

Where is amylase made?

Answer 8

• Salivary glands
• Pancreas
• Small intestine

Question 9

What does protease do?

Answer 9

Proteins → Amino acids

Question 10

Where is protease made?

Answer 10

• Stomach
• Pancreas
• Small intestine

Question 11

What does lipase do?

Answer 11

Lipids → Glycerol and fatty acids

Question 12

Where is lipase made?

Answer 12

• Pancreas
• Small intestine

Question 13

What does the stomach produce (not an enzyme)?

Answer 13

Hydrochloric acid

Question 14

What does the liver produce and for what purpose?

Answer 14

Bile to neutralise the acid that was added to food in the stomach

Question 15

How are enzymes used in the home?

Answer 15

Biological detergents may contain protease and lipase. These are more effective at low temperatures

Question 16

How are enzymes used in industry?

Answer 16

• Protease is used to ‘pre-digest’ protein in baby foods
• Carbohydrase is used to convert starch to sugar syrup
• Isomerase is used to convert glucose syrup into fructose syrup
  
  • This is much sweeter therefore more can be used in smaller quantities in slimming foods
• To bring about reactions at lower temperatures and pressures that would otherwise need lots of energy