MHT CET Medical202623 April 2026Evening ShiftBiologyBiomolecules (B)Actual
An enzyme catalyzes a reaction at a high rate at 37^ C but becomes inactive at 60^ C. This is because
Options
- AThe enzyme is denatured at high temperature.
- BThe enzyme is activated only at low temperature
- CThe substrate becomes inactive at high temperature.
- DThe enzyme-substrate complex becomes more stable
Correct answer
A. The enzyme is denatured at high temperature.
Step-by-step solution
Enzymes are generally proteinaceous in nature and have a specific three-dimensional structure that forms their active site. They work optimally at a specific temperature, which is around 37^ C for most human enzymes. At high temperatures such as 60^ C, the thermal energy disrupts the weak interactions (like hydrogen bonds and hydrophobic interactions) that maintain the enzyme's tertiary structure. This causes the enzyme to unfold and lose its specific shape, a process known as denaturation. Once denatured, the acti