Question #c96f9

1 Answer
Apr 10, 2015

Well, before answering the question, it's always useful to actually look at a Michaelis-Menten plot

The plot describes the rate of a catalyzed reaction, #v#, as a function of the concentration of the substrate, or #[S]#.

So, starting with the first option

  • A straight line connecting the points

This is clearly not correct, since the plot actually uses a curve to connect the points.

  • x-axis label of concentration units

As you can see, this is correct, the x-axis does indeed feature concentration units; more precisely, the x-axis of a Michaelis-Menten plot represents the concentration of the substrate, or #[S]#.

  • Points of initial velocity measured at #[S]# concentration

This one is correct as well, since various substrate concentration will have corresponding initial velocities on the y-axis of the plot.

  • A value of #K_m# half up the y-axis

I'm not sure about the wording on this one. #K_m# is not on the y-axis, but its x-axis value does correspond to a value half way up the y-axis.

So, if the question implies that #K_m# is half way on the y-axis, then it is incorrect. If it implies that #K_m# corresponds to a value located half way up the y-axis, then it is correct.

In this case, it would correspond to #V_"max"/2#, which is indeed half way between #V_"max"# and #0# on the y-axis.