A competitive inhibitor reduces the rate of an enzyme catalysed reaction by
Correct answer: C. occupying the active site because it resembles the substrate
- A. denaturing the enzyme permanently
- B. binding an allosteric site
- C. occupying the active site because it resembles the substrate
- D. lowering the temperature
Explanation
Substrate and inhibitor compete for the same site, so the inhibition can be overcome by increasing the substrate concentration and the maximum rate is eventually still reached. A non competitive inhibitor binds elsewhere, changes the shape of the enzyme and cannot be outcompeted, so it genuinely lowers the maximum rate. Many drugs are designed as competitive inhibitors of a specific enzyme.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? support@testustad.com
About Enzymes as Biocatalysts
Enzymes are protein or RNA biocatalysts that lower activation energy without being consumed, and their active sites bind specific substrates. The topic covers the lock and key and induced fit models, effects of temperature, pH and substrate concentration, cofactors, enzyme specificity, and competitive versus non-competitive inhibition.
Practise Macromolecules
299 free Macromolecules MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Chemistry questions like this
Chemistry is on 14 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Enzymes as Biocatalysts questions
Enzyme activity is lost above about 45 degrees Celsius because
The high specificity of an enzyme for its substrate is due to
Enzymes are described as biological catalysts because they
Heavy metal ions such as mercury and lead are poisonous partly because they
Each enzyme works fastest at a particular pH because a change in pH
An enzyme lowers the activation energy of a reaction by