Enzymes

Question 1

Catalyst

Answer 1

A substance which speeds up a chemical reaction, whilst remaining chemically unchanged

Question 2

Enzyme

Answer 2

A protein molecule that acts as a biological catalyst

Question 3

Active site

Answer 3

The site on an enzyme where the reactants bind

Question 4

Substrate

Answer 4

The material or chemical on which an enzyme acts

Question 5

Denature

Answer 5

To change the shape of an enzyme so that it can no longer function

Question 6

Digestion

Answer 6

The process of breaking down food into small molecules by digestive enzymes

Question 7

Amylase

Answer 7

The enzyme made in the salivary glands and the pancreas which speeds up the breakdown of starch into simple sugars

Question 8

Carbohydrase

Answer 8

An enzyme which speeds up the breakdown of carbohydrates into glucose

Question 9

Protease

Answer 9

An enzyme which speeds up the breakdown of proteins into amino acids

Question 10

Lipase

Answer 10

An enzyme which speeds up the breakdown of lipids into glycerol and fatty acids

Question 11

Lipid

Answer 11

An oil or fat

Question 12

Fatty acids

Answer 12

The building blocks of lipids

Question 13

Glycerol

Answer 13

The building blocks of lipids

Question 14

Bile

Answer 14

A yellow-green liquid made in the liver and stored in the gall bladder - released into the small intestine where it emulsifies fats

Question 15

Biological detergent

Answer 15

Washing detergent that contains enzymes

Question 16

Isomerase

Answer 16

An enzyme which converts one form of a molecule into another

Question 17

Fructose syrup

Answer 17

A sugar syrup

Question 18

What do proteins do?

Answer 18

Proteins act as structural components of tissues, as hormones, as antibodies and as catalysts

Question 19

How do enzymes work?

Answer 19

The substrate of the reaction fits into the active site of the enzyme and binds to it. The reaction then takes place rapidly, and the products are released from the surface of the enzyme

Question 20

What can affect enzyme activity?

Answer 20

High temperatures or the wrong pH value change the shape of the active site of an enzyme and stop it working

Question 21

Where are the digestive enzymes made?

Answer 21

Digestive enzymes are made in the pancreas and in glands in the stomach and small intestine

Question 22

How are enzymes involved in the digestion of food?

Answer 22

Different enzymes catalyse the breakdown of carbohydrates, proteins and fats into smaller, soluble molecules during digestion

Question 23

Why does the stomach contain hydrochloric acid?

Answer 23

The enzymes of the stomach work best in acidic conditions

Question 24

Why is bile important in digestion?

Answer 24

It neutralises acid and emulsifies fats, so helps the enzymes made by the pancreas and the small intestine work more effectively

Question 25

How do biological detergents work?

Answer 25

They contain proteases and lipases which catalyse the breakdown of proteins and fats

Question 26

How are enzymes made in industry?

Answer 26

Some microorganisms produce enzymes that pass out of the cells, and these are used in different ways

Question 27

How are enzymes used in industry?

Answer 27

• The diagnosis and treatment of disease such as diabetes
• Producing very sweet fructose syrup used in weight-loss foods

Question 28

What are the advantages and disadvantages of enzymes?

Answer 28

They help reactions happen at lower temperatures or pressures, which is cheaper and more environmentally friendly. However, they are expensive to produce, and must be used in specific conditions