Chapter 3

Question 1

V max

Answer 1

maximal velocity: rate of rxn when all enzyme is saturated with substrate

Question 2

Km

Answer 2

Michaelis constant: substrate concentration when reaction rate is 1/2 V max

Question 3

What does Km measure?

Answer 3

binding affinity of enzyme for substrate

low Km means tight binding

Question 4

Axis labels for enzyme reaction

Answer 4

X: substrate concentration [S]
Y: Initial reaction velocity (v)

Question 5

Inverse enzyme reaction called

Answer 5

Lineweaver-Burk plot

1/V vs 1/[S]

Question 6

1/V equation

Answer 6

Km/Vmax (1/[S]) + 1/Vmax

Question 7

5 ways cells regulate reaction rates

Answer 7

1. Regulate enzyme levels
2. Modify protein to inhibit/activate enzyme
3. Use allosteric activator to inhibit/activate enzyme
4. Competitive inhibition of enzyme
5. Make inactive enzyme that must be cleaved for activation