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INTERPRET THE DATA Phosphofructokinase is an enzyme that acts on fructose 6-phosphate at an early step in glucose breakdown (step 3 in Figure 7.9). Negative regulation of this enzyme by ATP and positive regulation by AMP control whether the sugar will continue on in the glycolytic pathway. Considering this graph, under which condition Is phosphofructokinase more active? Given this enzyme’s role in glycolysis, explain why it makes sense that ATP and AMP have these effects.
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