Limiting Factors Affecting Enzymes: Substrate Concentration

Question 1

The greater the substrate concentration,

Answer 1

the higher the rate of reaction:
As the number of substrate molecules increases, the likelihood of enzyme-substrate complex formation increases

Question 2

As the number of substrate molecules increases, the likelihood of enzyme-substrate complex formation increases

If the enzyme concentration remains fixed but the amount of substrate is increased past a certain point, however, all available active sites eventually

Answer 2

become saturated and any further increase in substrate concentration will not increase the reaction rate

When the active sites of the enzymes are all full, any substrate molecules that are added have nowhere to bind in order to form an enzyme-substrate complex

Question 3

If substrate concentration is continually increased but enzyme concentration is kept constant, there eventually comes a point where every enzyme active site is working continuously. At this point, the substrate molecules are effectively ‘queuing up’ for an active site to become available.

At this stage, the enzyme is working at its maximum possible rate, known as ……….. (V stands for velocity).

Answer 3

V max