Question

which statement is an example of a feedback mechanism in humans? an increase in exercise results in a decrease in the rate of respiration. increased muscle activity results in a decrease in heart rate. increased exposure to pathogenic bacteria results in an increase in the number of red blood cells produced. an increase in the level of blood sugar results in the pancreas increasing the amount of insulin it secretes.

Explanation:

To determine the example of a feedback mechanism, we analyze each option:

• Green: Exercise should increase respiration rate (not decrease), so incorrect.
• Orange: Increased muscle activity should increase heart rate (not decrease), so incorrect.
• Purple: Increased exposure to pathogenic bacteria would trigger immune responses, but red blood cells aren't the primary response to bacteria (white blood cells are), so this is not a typical feedback mechanism for bacteria exposure.
• Yellow: When blood sugar levels increase, the pancreas secretes more insulin (a negative feedback mechanism to lower blood sugar back to normal). This follows the feedback loop logic.

Answer:

Yellow. An increase in the level of blood sugar results in the pancreas increasing the amount of insulin it secretes.