5E: Thermodynamics & Kinetics

What does $V_{extmax}$ mean, and what MCAT clue matters?

Maximum rate at saturating substrate; depends on enzyme amount and catalytic turnover.

What does $K_m$ mean, and what MCAT clue matters?

$[S]$ when $v=V_{extmax}/2$; lower $K_m$ often means higher apparent affinity.

If one enzyme has a hyperbolic $v$ vs. $[S]$ curve and another has a sigmoidal curve, which is more likely allosteric?

The sigmoidal enzyme; sigmoidal kinetics suggest cooperativity.

What does $k_{cat}$ mean, and what MCAT clue matters?

Turnover number; product formed per enzyme per time at saturation.