The missing graph is in the attachment.
Answer: (a) [S] = 0.0016M
(b) Vmax = 3V; Vmax = ; Vmax =
(c) Enzyme A: black graph; Enzyme B = red graph
Explanation: <u>Enzyme</u> is a protein-based molecule that speed up the rate of a reaction. <u><em>Enzyme</em></u><em> </em><u><em>Kinetics</em></u> studies the reaction rates of it.
The relationship between substrate and rate of reaction is determined by the <u>Michaelis-Menten</u> <u>Equation</u>:
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in which:
V is initial velocity of reaction
Vmax is maximum rate of reaction when enzyme's active sites are saturated;
[S] is substrate concentration;
Km is measure of affinity between enzyme and its substrate;
(a) To determine concentration:
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0.75[S] = 0.00125
[S] = 0.0016M
For a Km of 0.005M, substrate's concentration is 0.0016M.
(b) Still using Michaelis-Menten:
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Rearraging for Vmax:
(b-I) for [S] = 1/2Km
3V
(b-II) for [S] = 2Km
(b-III) for [S] = 10Km
(c) Being the affinity between enzyme and substrate, the lower Km is the less substrate is needed to reach half of maximum velocity.
Km of enzyme A is 2μM and of enzyme B is 0.5μM.
Enzyme B has lower Km than enzyme A, which means the first will need a lower concnetration of substrate to reach half of Vmax.
Analyzing each plot, notice that the red-coloured graph reaches half at a lower concentration, therefore, red-coloured plot is for enzyme B, while black-coloured plot is for enzyme A
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