Chapter 12, Problem 2TC

Summary Introduction

To determine:

The homeostatic mechanism in the body in terms of positive and negative feedback.

Given:

a. The adrenal gland produces epinephrine in response to a hormone produced by the pituitary gland. In times of stress, the pituitary gland censuses the epinephrine in the blood and stops producing the hormone.

b. As the bladder fills with urine pressure sensors send a message to the brain with increasing frequency, signaling that the bladder must be emptied the more the bladder fills the more messages are sent.

c. When you drink, an excess of water specialized cells in your brain, as well as stretch receptors in your heart, detect the increase in blood volume; thus, both signals are transmitted to the kidney which increases the production of urine.