Chapter 6, Problem 13TYK

In the citric acid cycle, an enzyme oxidizes malate to oxaloacetate, with the production of NADH and the release of H⁺. You are studying this reaction using a suspension of bean cell mitochondria and a blue dye that loses its color as it takes up H⁺. You set up reaction mixtures with mitochondria, dye, and three different concentrations of malate (0.1 mg/L, 0.2 mg/L, and 0.3 mg/L). Which of the following graphs represents the results you would expect, and why?