Enzyme Saturation and Maximum Velocity — NEET Biology
✅ Asked in NEET 2024Which of the following graphs depicts the effect of substrate concentration on velocity of enzyme catalysed reaction?
Which of the following graphs depicts the effect of substrate concentration on velocity of enzyme catalysed reaction?
Answer & NCERT explanation
Correct answer: A — Graph showing velocity increasing with substrate concentration and saturating
The correct graph shows velocity increasing with substrate concentration until it reaches saturation (Vmax). This follows Michaelis-Menten kinetics from NCERT. Initially, velocity increases as more substrate binds to enzymes. At saturation, all enzyme active sites are occupied, so velocity plateaus regardless of further substrate addition.
Read more NCERT concept on the PYQ
With the increase in substrate concentration, the velocity of the enzymatic reaction rises at first. The reaction ultimately reaches a maximum velocity (Vmax) which is not exceeded by any further rise in concentration of the substrate. This is because the enzyme molecules are fewer than the substrate molecules and after saturation of these molecules, there are no free enzyme molecules to bind with the additional substrate molecules.
NTA tests understanding of enzyme kinetics: when substrate concentration increases, reaction velocity rises until Vmax is reached, after which it plateaus regardless of more substrate. The key concept is that Vmax depends on enzyme concentration, not substrate availability. Students commonly mistake thinking velocity increases indefinitely with substrate or confuse Vmax with substrate concentration. Remember: once all enzyme active sites are occupied (saturation), additional substrate cannot increase velocity because there are no free enzymes left to catalyze the reaction. This directly relates to enzyme efficiency and substrate availability in metabolic pathways.
What does NCERT say about With increase substrate concentration?
Has this concept appeared in NEET?
Which chapter is this from?
Through deep analysis of NEET and NTA, 88 of 90 questions from the NEET 2026 paper were matched straight from the MedicNEET Biology question bank.
88/90MedicNEET's Biology question bank is built from the same NCERT lines NTA picks repeatedly. Not random MCQs — questions crafted exactly like NTA crafts them.