Question

unit 1 cumulative test (characteristics of life, biomolecules, cell structure and transport) 2025
2 of 40
possible points: 2.13
which of the following best describes a positive feedback system?
∘ it reduces the effect of a stimulus
∘ it increases the effect of a stimulus
∘ it maintains balance by reversing changes
∘ it stops the body from responding to changes

Explanation:

To determine the correct answer, we analyze each option based on the definition of a positive feedback system:

• "It reduces the effect of a stimulus" describes negative feedback, not positive.
• "It increases the effect of a stimulus" matches the definition of positive feedback, where the response amplifies the original stimulus.
• "It maintains balance by reversing changes" is the role of negative feedback (homeostasis through reversal).
• "It stops the body from responding to changes" is incorrect as feedback systems are about responding, not stopping responses.

Answer:

B. It increases the effect of a stimulus (assuming the option identifiers are A, B, C, D with B being "It increases the effect of a stimulus")