Chapter 10, Problem 6STP

Summary Introduction

Introduction:

Enzymes are bio catalysts that are very important to life. They work by lowering the activation energy needed to start a chemical reaction. Without enzymes reactions would occur at a very slow rate. When an enzyme acts as a biological catalyst, the reaction occurs at a rate that is useful to cells. Many biological processes like digestion, photosynthesis, respiration, etc occur in the presence of enzymes.

Answer to Problem 6STP

Correct answer :

The correct answer is option C. to provide a unique spot for substrate binding

Explanation of Solution

Explanation/justification for the correct answer:

Option C. to provide a unique spot for substrate binding- Enzymes are bio catalysts that speed up the rate of chemical reaction in biological processes. Enzymes are also not used up in the reactions so they can be used again. Factors like pH, temperature, and other substances affect the activity of enzyme. They are highly specific in their action. Enzymes work by forming an enzyme- substrate complex which helps in breaking the chemical bonds in reactants and forming new bonds. Substrates interact with enzymes at specific places called active sites. The active sites and the substrates have complimentary shapes. The part labeled 1 in the given illustration denotes the active sites. Only substrates with similar shape and size as the active site will bind to the enzyme. Hence, this is the correct option.

Explanation for incorrect answer:

Option A. to make a reaction happen more slowly- Enzymes are bio catalysts that speed up the rate of chemical reaction in biological processes. They are highly specific in their action. The part labeled 1 in the given illustration denotes the active sites on enzymes. Only substrates with similar shape and size as the active site will bind to the enzyme.

Hence, this is not the correct option.

Option B. to make more reactants available to the substrate- The part labeled 1 in the given illustration denotes the active sites on enzymes. Only substrates with similar shape and size as the active site will bind to the enzyme. Hence, this is not the correct option.

Option D. to raise the activation energy for the reaction- Enzymes work by lowering the activation energy needed to start a chemical reaction. Without enzymes reactions would occur at a very slow rate. The part labeled 1 in the given illustration denotes the active sites on enzymes. Only substrates with similar shape and size as the active site will bind to the enzyme. Hence, this is not the correct option.