Enzyme Kinetics Lineweaver-Burk Plot

What is the relationship between the substrate concentration and the reaction rate when the enzyme is saturated with substrate?

The reaction rate is inversely proportional to the substrate concentration.
The reaction rate is independent of the substrate concentration. (correct)
The reaction rate increases exponentially with the substrate concentration.
The reaction rate is directly proportional to the substrate concentration.

What is the purpose of the Lineweaver-Burk plot?

To determine the maximum reaction velocity (Vmax) and the Michaelis constant (Km) of an enzyme. (correct)
To determine the affinity of the enzyme for the substrate.
To determine the rate-limiting step in the enzymatic reaction.
To determine the order of the reaction with respect to the substrate concentration.

What is the significance of the x-intercept in the Lineweaver-Burk plot?

It represents the value of Km.
It represents the value of the substrate concentration at which the reaction velocity is half of the maximum.
It represents the value of -1/Km. (correct)
It represents the value of 1/Vmax.

Why is it not always possible to determine the maximum reaction velocity (Vmax) from a plot of reaction velocity (vo) against substrate concentration ([S])?

Because the plot has a gradual upward slope at high substrate concentrations. (C) Signup and view all the answers

What information can be obtained from the slope of the Lineweaver-Burk plot?

The ratio of Km to Vmax. (D) Signup and view all the answers

What is the relationship between the Michaelis constant (Km) and the affinity of an enzyme for its substrate?

The lower the Km, the higher the affinity of the enzyme for the substrate. (A) Signup and view all the answers

What happens to the reaction rate when the substrate concentration is increased, while keeping the enzyme concentration constant?

The reaction rate increases until a saturation point is reached, after which it remains constant (A) Signup and view all the answers

What is the relationship between the reaction velocity and substrate concentration at low substrate concentrations?

The reaction velocity is directly proportional to the substrate concentration (B) Signup and view all the answers

What does the saturation point in the enzyme kinetics curve represent?

The point where all active sites on the enzyme are occupied by the substrate (C) Signup and view all the answers

What information can be obtained from a Lineweaver-Burk plot for an enzyme-catalyzed reaction?

The maximum reaction velocity ($V_{max}$) and the Michaelis constant ($K_m$) (B) Signup and view all the answers

What does a high value of the Michaelis constant ($K_m$) indicate about an enzyme?

The enzyme has a low affinity for the substrate (D) Signup and view all the answers

What is the order of the enzyme-catalyzed reaction with respect to the substrate concentration at low substrate concentrations?

First order (D) Signup and view all the answers

What does Km represent in the context of the Michaelis-Menten equation?

The substrate concentration at which the reaction velocity is half of the maximum velocity (B) Signup and view all the answers

How does an increase in substrate concentration affect the enzyme's reaction velocity according to the Michaelis-Menten equation?

Increases until it reaches Vmax, then decreases (A) Signup and view all the answers

In the context of enzyme kinetics, what does Vmax represent?

The maximum velocity the enzyme can reach in a reaction (A) Signup and view all the answers

What does the Lineweaver-Burk plot analyze in enzyme kinetics?

Reaction velocity at different substrate concentrations (A) Signup and view all the answers

What assumption is made about the rate of back reaction from product to substrate when deriving the Michaelis-Menten rate equation?

It is negligible because k-2 is approximately 0 (D) Signup and view all the answers

What does Michaelis constant Km calculate in enzyme kinetics?

Substrate concentration at half of the maximum velocity (C) Signup and view all the answers