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+--- Thread: Bio....2Q - maryam2009 (/showthread.php?tid=646608)
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Bio....2Q - maryam2009 - ArchivalUser - 01-13-2012
Consider a reaction that can be catalized by one of two enzymes,A and B,with the following kinetics
.....................Km(M).................Vmax(mmol/min)
A...................5*10^-6...............20
B...................5*10^-4...............30
At a concentration of 5*10^-4 M substrate,the velocity of the reaction catlized by enzyme A will be:
A.10
B.15
C.20
D.25
E.30
please explain your answer.Thank you
0 - ArchivalUser - 01-13-2012
ans, C, I think v max doesnot change with sub con
0 - ArchivalUser - 01-13-2012
v=v max[s]/Km+[s]
c is ans
0 - ArchivalUser - 01-13-2012
Agree with CC........
0 - ArchivalUser - 01-13-2012
the answer is C
As dr_eurekha mentioned
....the Vmax depends on Number of the enzymes and absolutely unrelated to Substrate concentrations....at the concentration 5*10^-4 ,enzyme A works at its Vmax,which is 20 mmol/min.
Thank you
0 - ArchivalUser - 01-13-2012
And you
0 - ArchivalUser - 01-22-2012
Hello,
Because I am a little confused, could you please help me understand the question? Does it ask about the velocity of the reaction or the Vmax of the reaction?
Thank you so much,
Elpida
0 - ArchivalUser - 01-22-2012
Vmax is the maximum velocity or rate at which the enzyme catalyzed a reaction...and it depends only on Number of the enzymes not substate concentrations,so increased or decreased [substreaes] will not change the amount of Vmax
....so in this case at the new concentration (5*10^-4) ,enzyme A works at its Vmax,which is 20 mmol/min.
.
0 - ArchivalUser - 01-22-2012
Vmax is the maximum velocity or rate at which the enzyme catalyzed a reaction...and it depends only on Number of the enzymes not *substrate concentrations,so increased or decreased* [substrates] will not change the amount of Vmax
....so in this case at the new concentration (5*10^-4) ,enzyme A works at its Vmax,which is 20 mmol/min.
0 - ArchivalUser - 01-23-2012
Thank you so much for your explanation. Is the substrate concentration power to -4 or power to 4?
Thank you again, I appreciate your help