AP BIOLOGY

Detailed explanation-1: -Most of the enzymes in human body function optimally at the physiological temperature that is 37∘C.

Detailed explanation-2: -This optimal temperature is usually around human body temperature (37.5 oC) for the enzymes in human cells. Above this temperature the enzyme structure begins to break down (denature) since at higher temperatures intra-and intermolecular bonds are broken as the enzyme molecules gain even more kinetic energy.

Detailed explanation-3: -The optimum temperature for most enzymes is about 98.6 degrees Fahrenheit (37 degrees Celsius). There are also enzymes that work well at lower and higher temperatures. For example, Arctic animals have enzymes adapted to lower optimal temperatures; animals in desert climates have enzymes adapted to higher temperatures.

Detailed explanation-4: -Optimum temperature is the temperature at which enzyme activity is maximum. In humans, this temperature is 37.5oC that is same as the normal body temperature. A rise in temperature above 40oC results in denaturation of the proteins of enzyme. Thus the correct answer is option A.

Detailed explanation-5: -As the temperature is increased enzyme activity increases to a maximum value at the optimum temperature (around 37 oC for most human enzymes).