3.3 Enzymes & Energy activation

Question 1

Enzymes

Answer 1

• Help chemical reactions
  take place at LOWER energy levels
  (allow your body to use less energy
  to drive reactions)
• DO NOT supply energy for reactions
• Help speed up the rate of reactions

Question 2

Activation Energy:

Answer 2

The amount of energy
required to start a reaction

A certain amount of energy is needed to help
break the bonds of chemicals

Question 3

Enzymes as Catalysts

Answer 3

Almost always PROTEINS

• Enzymes are usually written above the
  reaction arrow
• maltase catalyzes maltose

Question 4

Transition State:

Answer 4

Temporary state between
reactants and products (before new bonds are
formed)

Occurs when enough energy is required to
begin reaction

Question 5

What Provides Activation Energy?

Answer 5

Thermal Energy (ex. Lighting gasoline on fire
using a match)
- Often causes more and more reactions to take
place as more and more energy is released
- Hard to regulate

Catalyst (Enzymes)
- Allows reactions to occur using less energy
- Can be regulated to control rates of reaction

Question 6

How can Enzymes lower Activation Energy?

Answer 6

Helps reactants reach transition states in the
following ways:

1) BRINGS REACTANTS TOGETHER
- Orients molecules into position so they can bind

2) CHARGED ENZYMES HELP BREAK BONDS
- Charged functional groups help to attract
reactants and break bonds

3) ENZYME CHANGES SHAPE OF SUBSTRATE
- Enzyme changes shape to change the shape of the
substrate and break bonds