Which of the Following Is an Example of a Positive

question 38

Multiple Choice

Which of the following is an example of a positive feedback loop?

• A)a hummingbird maintaining a constant internal body temperature
• B)a person altering her breathing rate to keep blood pH between 7.35 and 7.45
• C)stress altering the normal menstrual cycle, which delays menstruation, which causes more stress
• D)the kidney retaining water when the organism becomes dehydrated

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Definitions:

Inspiratory Reserve Volume (IRV)

The additional amount of air that can be inhaled after a normal inhalation, increasing lung volume beyond the tidal volume.

Expiratory Reserve Volume (ERV)

The additional amount of air that can be forcibly exhaled after a normal exhalation.

Functional Residual Capacity (FRC)

The volume of air remaining in the lungs after a normal, passive exhalation, critical for gas exchange between breaths.

Tidal Volume (TV)

The volume of air moved into or out of the lungs during a normal breath, at rest.