Positive and negative feedback Original Scenario-Based Practice

Questions

1. 1.

   In an engineered cellular organism called Synthia, biologists design two communication pathways to control collective responses. Pathway 1 responds to an external signaling factor by stimulating its own intracellular cascade to produce and secrete even more of that same factor, rapidly spreading an amplified signal throughout the colony. Pathway 2 responds to a stress signal by activating a downstream inhibitor that directly blocks the initiating receptor, dampening the pathway once a specific response level is achieved. Which statement correctly classifies the feedback mechanisms operating in Pathway 1 and Pathway 2 and explains their functional roles?

   • A) Pathway 1 operates via negative feedback to preserve homeostatic stability, while Pathway 2 operates via positive feedback to drive an all-or-none threshold switch.
   • B) Pathway 1 operates via negative feedback to terminate signal transmission, while Pathway 2 operates via positive feedback to coordinate synchronized cell division.
   • C) Pathway 1 operates via positive feedback to amplify the signal and promote a decisive collective response, while Pathway 2 operates via negative feedback to restore homeostasis and prevent overactivation.
   • D) Pathway 1 and Pathway 2 both operate via positive feedback because each pathway relies on receptor stimulation to alter downstream intracellular enzymatic activity.

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