WORKSHOP 2-BIOC 3021 QUESTIONS AND ANSWERS 2024/2025 | VERIFIED
Why does a plot of V vs S taper off and eventually reach a plateau at higher S levels? - - When S
levels are high, the M-M plot actually approaches a limiting value of Vmax.
- At high (S), where V approximates Vmax, virtually all of the enzyme active sites are occupied by
substrate.
- The addition of more S would not significantly increase the rate of reaction, because the rate of
reaction is limited by the total active sites available; once all the sites are filled, the reaction can go no
faster.
What is the Michaelis-Menten Equation? - V = Vmax[S]/ [S] +km
The M-M Equation uses the terms (V), (Vmax), (S) and (Km). What do each of these terms mean? -
V= observable velocity of the reaction. Tells us how rapidly product (p) is being formed by the
reaction.
Vmax = fastest reaction rate possible under the given assay conditions. Has dimensions of change in
product concentration per unit time.
S = substrate concentration
Km = Michaelis Constant. Has units of concentration
What does the Km term tell us about an enzyme? - The Km tells us how efficient enzymes are at
low substrate levels
What does it signify if an enzyme has a low Km or a high Km? - - The Km tells us how efficient
enzymes are at low substrate levels?
- At low Km, the enzyme is very efficient at low substrate concentration. At high Km, enzymes are
inefficient at low substrate concentration.
What is the enzyme rate when the concentration of S = Km? - 1/2 Vmax.
Why is a V vs S plot linear at low S concentrations? - The M-M equation reduces to V = K[S] which
is the equation for a straight line.
This is b/c when Km is much greater than [S], the [S] term can be dropped from the denominator
Why does a plot of V vs S taper off and eventually reach a plateau at higher S levels? - - When S
levels are high, the M-M plot actually approaches a limiting value of Vmax.
- At high (S), where V approximates Vmax, virtually all of the enzyme active sites are occupied by
substrate.
- The addition of more S would not significantly increase the rate of reaction, because the rate of
reaction is limited by the total active sites available; once all the sites are filled, the reaction can go no
faster.
What is the Michaelis-Menten Equation? - V = Vmax[S]/ [S] +km
The M-M Equation uses the terms (V), (Vmax), (S) and (Km). What do each of these terms mean? -
V= observable velocity of the reaction. Tells us how rapidly product (p) is being formed by the
reaction.
Vmax = fastest reaction rate possible under the given assay conditions. Has dimensions of change in
product concentration per unit time.
S = substrate concentration
Km = Michaelis Constant. Has units of concentration
What does the Km term tell us about an enzyme? - The Km tells us how efficient enzymes are at
low substrate levels
What does it signify if an enzyme has a low Km or a high Km? - - The Km tells us how efficient
enzymes are at low substrate levels?
- At low Km, the enzyme is very efficient at low substrate concentration. At high Km, enzymes are
inefficient at low substrate concentration.
What is the enzyme rate when the concentration of S = Km? - 1/2 Vmax.
Why is a V vs S plot linear at low S concentrations? - The M-M equation reduces to V = K[S] which
is the equation for a straight line.
This is b/c when Km is much greater than [S], the [S] term can be dropped from the denominator
