Enzymes and Digestion

Question 1

Not all enzymes work inside cells. Give an example of where they don’t.

Answer 1

In the stomach because enzymes used in digestion are produced in the cells and then released into the stomach to be mixed with food

Question 2

What do digestive enzymes do?

Answer 2

Break down large insoluble molecules into smaller soluble ones

Question 3

Why do digestive enzymes break large molecules into smaller ones?

Answer 3

Because big molecules are too big to pass through the walls of the digestive system

Question 4

Where are digestive enzymes made?

Answer 4

In glands

Question 5

What are three examples of big molecules that are too big to pass through the walls of the digestive system?

Answer 5

Starch, proteins and fats

Question 6

What are four examples of smaller molecules that can pass easily through the walls of the digestive system?

Answer 6

Sugars, amino acids, glycerol and fatty acids

Question 7

What are the three digestive enzymes you need to know?

Answer 7

Amylase (a Carbohydrase), Protease and Lipase

Question 8

Where is amylase made?

Answer 8

The salivary glands, pancreas and small intestine

Question 9

What does amylase do?

Answer 9

Catalyses the digestion of starch into sugars

Question 10

Where does amylase catalyse its things?

Answer 10

In the mouth and small intestine

Question 11

Where is protease made?

Answer 11

In the stomach, the pancreas and the small intestine

Question 12

What does protease do?

Answer 12

Catalyses the breakdown of proteins into amino acids

Question 13

Where does protease catalyse its things?

Answer 13

In the stomach and small intestine

Question 14

What is protease called in the stomach?

Answer 14

Pepsin

Question 15

Where else does protease catalyse things apart from the stomach?

Answer 15

The small intestine

Question 16

Where is lipase made?

Answer 16

In the pancreas and small intestine

Question 17

What does lipase do?

Answer 17

Catalyses the breakdown of lipids (fats and oils) into fatty acids and glycerol

Question 18

What kind of conditions do protease enzymes work best?

Answer 18

In acidic conditions like the stomach

Question 19

What do glands in the stomach wall produce?

Answer 19

Hydrochloric acid to create the acidic conditions needed

Question 20

What kind of conditions do amylase and lipase work best?

Answer 20

In alkaline conditions like the small intestine

Question 21

What does the liver produce?

Answer 21

Bile

Question 22

Where is bile stored?

Answer 22

The gall bladder

Question 23

Is bile acidic or alkaline?

Answer 23

Alkaline

Question 24

What is the purpose of bile?

Answer 24

Bile is squirted into the small intestine to neutralise the acid from the stomach to make the conditions slightly alkaline so lipase and amylase can work there

Question 25

What does bile also do along with neutralising stomach acid?

Answer 25

It emulsifies fats

Question 26

What does emulsifies mean?

Answer 26

Breaks down into tiny droplets

Question 27

What is the point in bile emulsifying the fats in the small intestine?

Answer 27

It gives the lipase enzyme a larger surface area to work on which makes its digestion faster

Question 28

What is the breakdown of food catalysed by?

Answer 28

Enzymes

Question 29

Where are enzymes in the digestive system produced?

Answer 29

In glands and in the gut lining

Question 30

What enzyme do the salivary glands produce?

Answer 30

Amylase

Question 31

What does the liver produce?

Answer 31

Bile

Question 32

What does the gall bladder store?

Answer 32

Bile

Question 33

What happens in the large intestine?

Answer 33

Excess water is absorbed from food

Question 34

What enzymes does the pancreas produce?

Answer 34

Protease, amylase and lipase

Question 35

Where does the pancreas release its enzymes into?

Answer 35

The small intestine

Question 36

What happens in the small intestine?

Answer 36

Digested food is absorbed out of the digestive system and into the blood

Question 37

What enzymes does the small intestine produce? (hint - the same as the pancreas)

Answer 37

Protease, amylase and lipase

Question 38

What does the stomach do with its muscular walls?

Answer 38

Pummels the food

Question 39

What enzyme does the stomach produce?

Answer 39

Protease (pepsin)

Question 40

What else does the stomach produce apart from the enzyme?

Answer 40

Hydrochloric acid

Question 41

Why does the stomach produce hydrochloric acid? (2 reasons)

Answer 41

To kill bacteria, and to give the right pH for the protease enzyme to work, which is 2 - acidic

Question 42

What happens in the rectum?

Answer 42

Faeces is stored

Question 43

What is faeces mainly made up of?

Answer 43

indigestible food