Enzymes

Question 1

What are the three types of enzymes?

Answer 1

Carbohydrase, Protease, Lipase

Question 2

What is the product when carbohydrases react with their substrate (carbohydrates)?

Answer 2

Simple sugars e.g. glucose

Question 3

What is the product when protease reacts with its substrate (proteins)?

Answer 3

Amino acids

Question 4

What is the product when lipase reacts with its substrate (lipids)?

Answer 4

Fatty acids and glycerol

Question 5

What is an enzyme substrate complex?

Answer 5

When ab enzyme’s active site fits with a specifically shaped substrate.

Question 6

What is an enzyme?

Answer 6

An enzyme is a protein which acts as a biological catalyst. A Catalyst is a chemical which speeds up a reaction without being used up.

Question 7

What is a catabolic reaction?

Answer 7

When an enzyme reacts to breakdown complex substances into simple component products.

Question 8

What is a anabolic reaction?

Answer 8

When an enzyme reacts to build complex products from simple components.

Question 9

What is an example of an enzyme which prefers to work in acidic conditions

Answer 9

Pepsin in the stomach

Question 10

What is an example of an enzyme which prefers to work in alkaline conditions

Answer 10

Protease in the duodenum

Question 11

What happens to enzymes when above 37°C?

Answer 11

They denature

Question 12

Why are enzymes needed in seed germination?

Answer 12

The starch inosine has to be broken down into sugar embryo is going to start growing, the enzyme is amylase

Question 13

How does the production of amylase change with the age of the seed?

Answer 13

The older the seed, the smaller the amount of amylase being produced. This is because as the ceedling develops it is able to photosynthesise to make it’s own food and no longer needs to rely on its feet reserve.

Question 14

How does pH affect enzyme activity?

Answer 14

Each enzyme has its own optimum pH. pH affects enzyme activity since changing the acid or base conditions around and enzyme molecule effects its three-dimensional shape and can denature the enzyme.

Question 15

What is the optimum pH for amalyse?

Answer 15

7.5 (slightly basic). Ideal for the mouth and small intestine.

Question 16

Why does is increasing temperature increase enzyme activity?

Answer 16

A higher temperature speeds up the movement of substrate molecules, so that when they collide with enzymes they have more energy and are more likely to bind to the active site.

Question 17

Why can temperatures over 40°C denature enzymes?

Answer 17

As temperatures rise enzymes vibrate more. Eventually the enzyme molecules vibrate so much that they become denatured. They loose their three-dimensional shape and can no longer bind to their substrate.

Question 18

How are enzymes used in biological washing powders?

Answer 18

Lipase and protease are used in washing powders, as they give the added advantage of working at lower temperatures. They can remove lipids (e.g. from fatty foods or greasy fingerprints) or proteins (e.g. from blood).

Question 19

How are enzymes used in fruit juices?

Answer 19

Pectinase is used as it breaks down small pieces of plant tissue to turn cloudy fruit juice into clear fruit juice.

Question 20

How are enzymes made?

Answer 20

They are produced by microorganisms, usually bacteria or fungi, in a fermenter.

Question 21

What is an example of an enzyme which has a acidic optimum pH?

Answer 21

Pepsin (that’s why it functions well in the stomach)

Question 22

What is an example of a enzyme which has a alkaline optimum pH?

Answer 22

Protease (in the duodenum)