Free Enzymes MCQs with Answers

• A. Enzymes
• B. Reactant
• C. Product
• D. Substrate

Explanation: Inhibitors bind to the enzymes, and decrease their activity. They cannot bind to substrate, product or reactant.

• A. Competitive inhibitors
• B. Noncompetitive inhibitors
• C. Irreversible inhibitors
• D. Both A and B

Explanation: Competitive inhibition is reversible because the inhibitor forms weak linkages with the enzyme.

• A. Enzyme
• B. Substrate
• C. ES complex
• D. All of these

Explanation: Option C is correct since uncompetitive inhibition occurs when an inhibitor binds to an allosteric site of an enzyme, but only when the…

• A. Lock
• B. Key
• C. Both of these options are correct
• D. None of these options are correct

Explanation: Lock andkey model assumes that like a particular key opens a particular lock, a specific enzyme(key) acts upon a particular substrate…

• A. By adding activation energy requirements
• B. By lowering the activation energy requirements
• C. By decreasing the concentration of products
• D. By increasing the concentration of products
• E. All of the the given options

Explanation: Enzymes are biological catalysts that increase the rate of reaction by lowering the activation of the energy of the reactions.

• A. Irreversible inhibitors
• B. Competitive irreversible inhibitors
• C. Non-competitive inhibitors
• D. Reversible inhibitors

Explanation: Penicillin functions as a competitive inhibitor by mimicking the substrate that the bacterial enzyme would normally act upon, thus binding…

• A. 32o F
• B. 46oC
• C. 313K
• D. 37oC

Explanation: The optimum temperature for enzymes in the human body is 37ºC, which is crucial for maintaining the proper enzymatic activity necessary…

• A. A friend of mine is coming to visit next week.
• B. The friend of mine is coming to visit next week.
• C. Friend of mine is coming to visit next week.
• D. A friend of me is coming to visit next week.

Explanation: The correct answer is A. A friend of mine is coming to visit next week.

• A. 90
• B. 20
• C. 10
• D. 1
• E. None of these

Explanation: Explanation for this question will be added soon.

• A. Enzymes are mostly proteins but some are lipids also
• B. Enzymes are denatured at high temperatures
• C. Enzymes are highly specific
• D. Enzymes require optimum pH and temperature for maximum activity

Explanation: Option A: Enzymes are mostly proteins but some are lipids also: This statement is incorrect.

• A. 1010
• B. 2010
• C. 1020
• D. 1510

Explanation: Yes, enzymes can speed up reactions by factors of up to 1010 (ten billion) or even higher.

• A. The primary structure of enzymes
• B. The secondary structure of enzymes
• C. Tertiary structure of enzymes
• D. Quarternary structure of enzymes

Explanation: Tertiary structure of enzymes. Enzyme-substrate specificity arises from the unique three-dimensional shape of the enzyme's active site…

• A. Apoenzyme
• B. Holoenzyme
• C. Activated enzyme
• D. Both B and C

Explanation: Correct option is B. The answer is holoenzyme. An enzyme is a protein that catalyzes a chemical reaction.

• A. Competitive inhibitor binds to active site
• B. The substrate binds to active site
• C. Enzymes work best in low pH
• D. Both competitive inhibitor binding to alternative site & substrate binding to active site

Explanation: Option C is the incorrect one as enzymes work at optimum pH rather than low pH.

• A. Enzyme is inhibited by the product being produced
• B. Enzyme works normally for regulatory mechanism
• C. Enzyme remains unaffected by product concentration
• D. Enzyme is inhibited irreversibly

Explanation: Feedback regulation of an enzyme occurs when a product of the reaction binds to an allosteric site on the enzyme and affects its catalytic…

• A. Activator
• B. Inhibitor
• C. Substrate
• D. Both A and B

Explanation: Enzymes can be regulated by other molecules that either increase or reduce their activity.

• A. Malonate act as inhibitor
• B. Enzyme shape distorted
• C. Competition for active site
• D. Inactive enzyme gettlng reactivated

Explanation: A noncompetitive inhibitor binds to the enzyme away from the active site, altering the shape of the enzyme so that even if the substrate…

• A. Allosteric site
• B. Active site
• C. Passive site
• D. Regulatory site

Explanation: Non-competitive inhibitors bind to enzymes at allosteric sites, which are distinct from the active site.

• A. Competitive inhibitors
• B. Non-competitive inhibitors
• C. Co-enzymes
• D. Activators

Explanation: Enzymes' productivity is reduced by blocking the active site due to similar shapes, is associated with "competitive inhibitors."…

• A. Increases enzyme activity
• B. Doesn't change enzyme activity
• C. Decreases enzyme activity
• D. None of these

Explanation: An enzyme inhibitor is a molecule that binds to an enzyme and blocks its activity.