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Flashcards in Biochemistry Deck (16):
1

Vmax

The maximal velocity of a reaction

2

Km

The substrate concentration that brings about half Vmax

3

How can you experimentally determine Vmax?

Taking the initial velocities of reactions using known substrate concentrations. Then plot the initial velocities against substrate concentration. The point they plataue off at is almost Vmax.

4

Why is experimentally determing Vmax not effective?

No matter the substrate concentration- the reactions will never reach Vmax.

5

What is the original equation for V and what does it get transformed into?

V= Vmax[S]/km + [S]
1/V = Km+ [S]/ Vmax[S]
1/v= Km/Vmax[S] + [S]/Vmax[S]
1/v= km/Vmax x 1/{S] + 1/Vmax
y= m x + c

6

What is the gradient of the lineweaver Burke plot?

Km/Vmax

7

What is the y interception?

Vmax

8

What is the x interception?

Km

9

In competitive antagonism- what changes on the Lineweaver Burke plot

Vmax stays the same
Km varies

10

In non-competitive antagonism- what changes on the lineweaver burke plot?

Vmax changes
Km stays the same.

11

Enzymes can have the same Vmax but different Km's?

True

12

A low Km means

Little substrate is needed to get a half maximal response.

13

A high Km means

Lots of substrate is needed to get a half maximal response.

14

Allosteric enzymes follow the michaelis menten kinetics. True or false

False

15

What sort of curve do allosteric enzymes create?

Sigmoidal

16

What is meant by feedback initiation?

Generally enzymes are in a long chain to make one product. Commonly, once this product has been created it inhibits the rate limiting enzyme in that chain so that there is little substrate available. This limits the reaction.