[Campbell Biology P.1051] The text describes a significant signal amplification in the epinep... | Practice Question

The text describes a significant signal amplification in the epinephrine pathway. If each of the three enzymes in the cascade carried out 1,000 reactions, how many glycogen molecules would be cleaved by the binding of one molecule of epinephrine to its receptor?

  • A: 1,000 glycogen molecules.
  • B: 1,000,000 (10^6) glycogen molecules.
  • C: 1,000,000,000 (10^9) glycogen molecules.
  • D: 3,000 glycogen molecules.

Explanation

The text explicitly states that if each of the three enzymes carried out 1,000 reactions, the binding of one molecule of epinephrine would trigger the cleavage of a billion 10^3 x 10^3 x 10^3 glycogen molecules. This demonstrates the powerful multiplicative nature of signal amplification in a biochemical cascade.