Proteins & Enzymes

Question 1

What are enzymes made from?

Answer 1

Proteins

Question 2

What determines the function of a protein?

Answer 2

The order of amino acids

Question 3

What is the function of an enzyme?

Answer 3

Speed up chemical reactions. E.g. amylase, catalase and phosphorylase

Question 4

What is the function of an antibody?

Answer 4

Produced by white blood cells and protects the body from harmful microbes

Question 5

What is the function of hormones?

Answer 5

Chemical messengers. E.g. testosterone, oestrogen and adrenaline

Question 6

What is the function of transport proteins?

Answer 6

Movement of molecules. E.g. membrane proteins

Question 7

What is the function of structural proteins?

Answer 7

Provide shape and support. E.g. collagen, keratin and myosin

Question 8

What are the properties of enzymes?

Answer 8

-Enzymes are made from proteins and are produced by all living cells
-They are biological catalysts which increases the rate of chemical reactions
-Enzymes are reusable as they are unchanged by the chemical reaction
-Enzymes have an active site which is specific to one type of substrate
-They are most active at optimum conditions and become denatured at high temperatures / PH levels

Question 9

What is the importance of enzymes?

Answer 9

Speeds up chemical reactions in the body, that would otherwise happen to slowly for life

Question 10

Describe an enzyme reaction:

Answer 10

Enzyme
Substrate ➡️ product

Question 11

Explain the specificity of enzymes for their substrates:

Answer 11

The active site of each type of enzyme has a different shape from any other type of enzyme (complementary) so that it will only bind to one type of substrate. This is called specificity

Question 12

Give examples of a degradation reaction:

Answer 12

Starch is a large, complex molecule. An enzyme called amylase can degrade (break down) starch and turn it into a smaller sugar called maltose

                   Amylase
  Starch.          ➡️.        Maltose

Lipase breaks down fats into fatty acids and glycerol

             Lipase
Fats.        ➡️.       Fatty acids + glycerol

Question 13

Give an example of a synthesis reaction:

Answer 13

The conversion of glucose-1-phosphate into starch is a synthesis reaction

                                    Phosphorylase glucose-1-phosphate            ➡️.                Starch

Question 14

Name factors which affect the activity of an enzyme:

Answer 14

Temperature and PH

Question 15

What is meant by the term ‘Optimum Conditions’

Answer 15

The conditions at which an enzyme is most active

Question 16

What happens when an enzyme becomes denatured?

Answer 16

An enzyme becomes denatures when it exceeds its optimum conditions. It will cause the active site of the enzyme to change shape and loose its activity