Question

At what pH and temperature the enzymes are highly efficient?

Answer 1

Enzymes act as biological catalysts that accelerate the chemical reactions taking place in the body. The molecules on which an enzyme acts are called substrates. The enzyme converts the substrate into different molecules called products. The rate of enzyme activity is affected by many factors like temperature, pH, water, concentration of enzyme, accumulation of end products etc.

Complete answer:
Temperature plays an important role in the rate of enzyme activity. At low temperatures, the enzymes do not get activated. At very high temperatures the intramolecular bonds in the enzyme break and lead to denaturation. Hence, the activity of the enzymes is optimum at around $30^\circ$C to $50^\circ$C.
The enzymes are of different types- alkaline, acidic and neutral. Due to this, the optimum pH varies with each enzyme. Enzymes show optimal activity only over a limited range of pH. Changes in pH can break the intra and intermolecular bonds in the enzymes, which will greatly affect its effectiveness. The optimum pH of most enzymes is in the range of $4$ to $9$.

Note:
Water also plays an important role in enzyme activity. The enzyme activity is greatly suppressed in absence of water. As water provides a medium for enzyme reaction to take place, proper hydration of the cells is necessary for optimal enzyme activity. Water also acts as one of the reactants. The concentration of enzymes is one of the factors affecting the reaction rate. Increased concentration of the enzyme will increase the rate of catalytic reaction as it provides more active sites.