Topic 2c- Enzymes and digestion

Question 1

Define a catalyst?

Answer 1

A catalyst is a substance which increases the speed of a reaction.

Question 2

How does an enzyme break down a substance?

Answer 2

1. The enzyme has an active site with a unique shape that fits onto the substrate only.
2. Because the enzyme fits the substrate, the substrate can be catalysed to break down into products.

Question 3

What conditions must be kept under control within the body to keep enzymes in their optimal conditions?

Answer 3

• Temperature (37°C)
• pH

Question 4

In what ways is food broken down?

Answer 4

• Mechanical digestion (teeth grinding and stomach churning food)
• Chemical digestion (enzymes)

Question 5

What enzyme breaks down starch and what does it break down into?

Answer 5

Amylase, to produce maltose (and other sugars)

Question 6

What enzyme breaks down protein and what does it break down into?

Answer 6

Protease, to produce amino acids

Question 7

What enzyme breaks down lipids and what does it break down into?

Answer 7

Lipase, into glycerol and fatty acids.

Question 7

Where is carbohydrase made?

Answer 7

• salivary glands
• pancreas
• small intestine

Question 8

Where is protease made?

Answer 8

• stomach
• pancreas
• small intestine

Question 9

Where is lipase made?

Answer 9

• pancreas
• small intestine

Question 10

What is the function of bile?

Answer 10

• neutralises the stomach acid going into the small intestine to make it alkaline so that the enzymes in the small intestine can work
• it emulsifies fats (breaks down fats into tiny droplets giving bigger s.a. for lipase to work on)

Question 11

Where is bile produced and where does it end up?

Answer 11

Produced in the liver before being stored in the gall bladder and then going into the small intestine.