[Campbell Biology P.59] In a laboratory experiment, a scientist introduces a chemical that ... | Practice Question

In a laboratory experiment, a scientist introduces a chemical that causes a cell to produce more of a specific enzyme. This enzyme then acts as a catalyst for a reaction that further increases the production of the same enzyme. What type of regulatory mechanism does this scenario most closely describe?

  • A: Negative feedback, because the enzyme's action controls its own production.
  • B: Positive feedback, because the product (enzyme) amplifies its own production.
  • C: Homeostasis, as the system is trying to maintain balance.
  • D: Allosteric regulation, as an enzyme is involved.

Explanation

The scenario describes a situation where the product the enzyme acts to further increase its own production. This amplification loop is the defining characteristic of positive feedback, as explained in the text with the example of blood clotting, where platelets attract more platelets, speeding up the process.