Factors affecting enzyme activity

Which of the following does not affect enzyme activity?

• temperature

• pH

• substrate concentration

• sugar

Which refers to a molecule upon which an enzyme acts?

• cofactor

• coenzyme

• substrate

• substance

What will happen when enzyme is denatured?

• A proton is added or removed from the enzyme.

• It reaches its temperature at which it exhibits maximum activity.

• A substance binds to it which slows or stops its normal catalytic function.

• It changes shape and the active site no longer matches the shape of the substrate molecule.

This graph shows the enzyme activity when substrate concentration is increased. What is the reason of this enzyme activity pattern?

• There is no available substrate.

• The active site changes its shape, thus, preventing the substrate from binding.

• High substrate concentration affects the temperature at which enzymes work best.

• Enzymes are all occupied, the incoming substrate molecules must wait for an active empty site.

Why an increased in temperature (up to the optimum temperature) increases the enzyme reaction?

• Because kinetic energy of molecules decreases.

• Because kinetic energy of molecules increases.

• Because denaturation of enzymes occurs.

• Because inhibitors are eliminated at this condition.

As temperature increase, collisions occur more frequently and with more energy - so the rate of reaction _____________.

BUT above a certain temperature, the structure of the enzyme changes.

The enzyme then loses its shape/unfolds as does the active site. This means the enzyme activity is reduced and the enzyme is said to be ________________.

At first, the substrate no longer fits into the active site very well and the reaction rate is just slowing down. Eventually though the substrate no longer fits the active site at all and so the reaction ________________.

Tags

NGSS.HS-PS1-2

The temperature at which there are maximum number of collisions is the _____________ ____________________.

pH and enzyme activity

Most enzymes work best at pH ______ - neutral