Enzymes

What are enzymes?

Proteins

What is the function of enzymes?

Biological catalysts that speed up the rate if reactions causing insoluble larger molecules to break down into smaller molecules

What do enzymes break down?

Substrates

Where does the substrate fit into an enzyme?

Active site

Why are enzymes considered catalysts?

They decrease the amount of energy required to break the bonds in the substrate

What is the action of enzymes referred to as?

The lock and key model

Explain the lock and key model of enzyme action

The active site of the enzyme only fits one substrate (it is substrate specific)

complementary shape

Which enzyme breaks down carbohydrate?

Carbohydrase

Which enzyme breaks down carbohydrate?

Amylase

Which enzyme breaks down protein?

Protease

Which enzyme breaks down fats?

Lipase

What are carbohydrates broken down into?

Simple sugars (e.g. glucose, lactose)

What are proteins broken down into?

Amino acids

What are fats broken down into?

Glycerol and fatty acids

Where does carbohydrase act?

Small intestine

Where does amylase act?

Mouth and small intestine

Where does protease act?

Stomach and small intestine

Where does lipase act?

Small intestine

What are inhibitors?

Molecules that limit the action of enzymes

How do enzyme inhibitors work?

It gets into the active site and stays there, preventing the substrate from binding

State the term that describes the best temperature/pH for ezyme action

Optimum

What happens to the rate of reaction as temperature is increased?

The rate of reaction increases until the temperature reaches the optimum for that enzyme

What happens to enzymes above their optimum conditions?

They become denatured

What do you understand by the term denatured?

The shape of the enzyme’s active site irreversibly changeS so it can no longer bind with the substrate

State a commercial use for enzymes

Biological washing powders

What type of enzymes must be used in washing powders?

Thermostable enzymes

What do you understand by the term thermostable enzyme?

Enzymes that can still work when the temperature exceeds the optimum.

What happens when there is higher temperature for enzymes

1. High temp

2. more kinetic energy

3. more collisions

4. more enzyme substrate complexes formed