Question

All of the following is true about an enzymes except

• A. Enzyme activity is affected by changes in temperature.
• B. Enzymes change the rate at which biochemical reactions proceed.
• C. Enzyme activity is affected by large shifts in pH.
• D. Enzymes often require the presence of cofactors or coenzymes to become active.
• E. Enzymes are assembled from vitamin subunits.

Answer 1

The correct option is E Enzymes are assembled from vitamin subunits.

Enzymes are assembled from protein subunits and function within a specific range of temperature and pH only as extremes of temperature and pH alter the secondary and tertiary structure of proteins. The energy required for formation of the transition state is termed as activation energy. Enzymes enhance the rate of reaction by lowering down the activation energy of transition state. The cofactor is nonprotein substance required by an enzyme for normal activity. Coenzymes are organic substances that serve as cofactors. Thus, the correct answer is option E.