Solutions For 9780131905429 Chapter 2 Problem 25A

Temperature – Enzymes work best at an optimum temperature.

Below this, an increase in temperature provides more kinetic energy to the molecules involved. The numbers of collisions between enzyme and substrate will increase so the rate will too.

Above the temperature, and the enzymes are denatured. Bonds holding the structure together will be broken and the active site loses its shape and will no longer work.

This optimal temperature is usually around human body temperature () for the enzymes in human cells.

PH – Each enzyme works within quite a small PH range. There is a PH at which its activity is greatest is the optimal PH. If the PH changes much from the optimum, the chemical nature of the amino acids can change. This may result in the bonds and so the tertiary structure may break down. The active site will be disrupted and the enzyme will be denatured.

Concentration of enzyme and substrate –

The rate of an enzyme catalyzed reaction depends on the concentrations of enzyme and substrate. As the concentration of either is increased, the rate of reaction increases.