[Campbell Biology P.265] Based on Sutherland's experiments with epinephrine and glycogen pho... | Practice Question

Based on Sutherland's experiments with epinephrine and glycogen phosphorylase, which conclusion is most strongly supported?

  • A: Epinephrine directly binds to and activates glycogen phosphorylase.
  • B: Glycogen phosphorylase can be activated by epinephrine in a cell-free solution containing only the enzyme and its substrate.
  • C: Epinephrine's effect on glycogen breakdown requires an intact, membrane-bound cell.
  • D: Epinephrine mobilizes fuel reserves by directly producing glucose 6-phosphate from glycogen.

Explanation

Sutherland's experiments showed two key findings: epinephrine does not directly interact with glycogen phosphorylase implying intermediate steps , and an intact, membrane-bound cell is necessary for the signal transmission to occur. Option C directly reflects the second key finding.