Biology Enzymes UHS 2024
PMDC Verified Question 10 of 79
Which of the following statement is incorrect regarding rate of enzymatic action?
A
Increase in enzyme concentration increases the rate
B
Increase in enzyme concentration reduces the rate
C
All enzymes work at their maximum rate at optimum
D
All enzymes work at their maximum rate at optimum pH temperature
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option B: Increase in enzyme concentration reduces the rate
Concept:

Enzyme kinetics relies on collision theory. More enzymes mean more available active sites for substrates to collide with.

Solution:

  • If substrate concentration is abundant, adding more enzyme molecules directly increases the number of available active sites.
  • This leads to a higher frequency of successful collisions, linearly increasing the reaction rate.
  • Therefore, the statement that an increase in enzyme concentration reduces the rate is fundamentally backwards and mathematically incorrect.


Why other options are incorrect:

Option A is a true statement. Options C and D are true; peak performance (maximum rate) is achieved when environmental factors (pH and temperature) are exactly at their optimal levels.

Quality & Fidelity Assurance: Every question on BeambePrep is rigorously curated against the official PMDC syllabus with zero filler, zero out-of-syllabus content, and zero typos. When an authentic past paper originally contained a historical mistake or ambiguity from the examining board (such as UHS or NUMS), BeambePrep faithfully reflects the original paper while detailing the nuance and scientific consensus in the autopsy above.

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