Question 1 (1 point) Muscle normally constitutes the largest fraction of body ma
ID: 132144 • Letter: Q
Question
Question 1 (1 point) Muscle normally constitutes the largest fraction of body mass and the widest oscillation of metabolic need. At rest, muscle cells have high energy charge. Active muscle convert a significant fraction of ATP to AMP. Choose all of the following that are likely in a muscle cell given abundant extracellular glucose. 1) increased muscle contraction reduces cellular ATP/AMP ratio the rate of phosphofructokinase is stimulated by the rise in cellular ATP 2) produced by muscle contration the rate of phosphofructokinase is stimulated by shifting the pool of adenine 3) nucleotide in favor of ATP the rate of glycolysis is inhibited in resting muscle owing to an increase in the 4) ATPI/IAMP] ratioExplanation / Answer
Active muscles convert a significant portion of ATP into AMP. When there is abundant extracellular glucose, the active muscles need ATP and therefore phosphofructokinase enzyme is stimulated to fast forward the glycolytic reactions which produce ATP needed for muscle contraction. In the resting muscle, the rate of glycolysis is inhibited owing to an increase in ATP/AMP ratio which inhibits phosphofructokinase enzyme. So, the correct answers for this question are options 3 and 4.