Module 2 Section 4 - Factors Affecting Enzyme Activity

Question 1

What are the four factors that affect enzyme activity

Answer 1

-Temperature
-pH
-Enzyme Concnetration
-Substrate concentration

Question 2

When the rate of an enzyme controlled reaction is increased what is also increased

Answer 2

The temperature

Question 3

More heat means ….

Answer 3

More kinetic energy

Question 4

More kinetic energy means…..

Answer 4

Molecules moves faster

Question 5

Because the molecules move faster, what does it lead to

Answer 5

Makes the enzymes more likely to collide with the substrate molecule

Question 6

The energy of collisions increases meaning

Answer 6

Each collision is more likely to result in a reaction

Question 7

What happens if the temperature is too high

Answer 7

The reaction stops

Question 8

The rise in temperature makes the enzymes molecules….

Answer 8

Vibrate more

Question 9

If the temperature goes above a certain level….

Answer 9

This vibration breaks some of the bonds that hole the enzyme in shape

Question 10

The active site

Answer 10

Changes shape and the enzyme and substrate no longer fit together

Question 11

When the active site changes shape and the enzyme and substrate don’t fit together it means….

Answer 11

That the enzyme is denatured - no longer functions as a catalyst

Question 12

All enzymes have an….

Answer 12

Optimum pH

Question 13

What do most human enzymes best work at

Answer 13

pH 7 (neutral), but there are exceptions

Question 14

What happens if the pH is above or below optimum

Answer 14

The H+ and OH+ ions found in acids and alkalis can mess up the ionic bonds and hydrogen bonds that hole enzyme tertiary structure in place. This makes the active site change shape meaning the enzyme becomes denatured

Question 15

The more enzyme molecules there are in a solution…

Answer 15

the more likely a substrate molecule is to collide with one and form an enzyme substrate complex

Question 16

Increasing concentration of enzyme….

Answer 16

Increases rate of reaction

Question 17

What happens if the amount of substrate is limited

Answer 17

There will be a point where there are more than enough enzyme molecules to deal with all available substrate so adding more enzyme has no further effect

Question 18

The higher the substrate complex

Answer 18

The faster the reaction

Question 19

The more substrate molecules means….

Answer 19

A collision between substrate and enzyme is more likely so more active sites will be used

Question 20

What happens after the saturation point

Answer 20

There are so many substrate molecules that the enzymes have about as they can cope with and adding more substrate makes no difference to the rate of reaction

Question 21

Substrate concentration decreases….

Answer 21

With time during a reaction, so if no other variables are changed the rate of reaction will decrease over time too.