Question

Each of the following are true of enzymes except

A. They can be used over and over
B. They may or may not require cofactors
C. Their active site is specific to the substrate
D. Increase initial energy required for a reaction to start

Answer 1

The incorrect statement about enzymes is that they increase the initial energy required for a reaction. Enzymes lower the activation energy, making chemical reactions occur more readily, and they are specific to the substrates they bind.

Step-by-step explanation:

The statement that is not true about enzymes is that they increase the initial energy required for a reaction to start. Enzymes act as biological catalysts that specifically accelerate the rate of chemical reactions within the body without being consumed by the reaction. They achieve this by lowering the activation energy needed for a reaction to begin.

Enzymes are composed mostly of amino acids, making them proteins that are highly specialized to bind to certain substrates—this is what makes them so specific. Enzymes do not affect the overall free energy change (ΔG) of a reaction and cannot turn endergonic reactions into exergonic ones. The key role of enzymes is to make it easier for reactions to occur by lowering the activation barrier, not increasing it.