In a 1929 paper defining physiological homeostasis, Walter Cannon stated the four postulates below. Some systems of the body are under antagonistic control. The nervous system has a role in preserving the fitness of the internal environment. One chemical signal can have different effects in different tissues. Some systems of the body are under tonic control. Choose to answer only one of the following questions. Which postulate applies most closely to the concept that multiple receptors exist for a given ligand? Explain your answer using examples as needed. Which postulate applies most closely to the effects of glucagon and insulin? Explain your answer using examples as needed.

Hormones released from the hypothalamus and pituitary are _____.

Which of the following is true regarding sperm?

What enzyme is involved in all of the following functions? Water production for the anterior segment of the eye. Bicarbonate production in erythrocytes. Bicarbonate production in the pancreas. Hydrogen ion production by parietal cells of the stomach. Hydrogen ion production in cerebrospinal fluid. Carbon dioxide production in certain plants.

Which of the following would result in passive immunity?

In the pregnant woman, what organ takes over secretion of estrogens and progesterone after her corpus luteum degenerates?

Which of the following enhances oxygen unloading from hemoglobin?

A patient has a tumor that causes her to secrete an excess amount of vasopressin. You would expect that the excessive level of vasopressin will ultimately cause ________.

GnRH (gonadotropin releasing hormone) directly controls the release of _____. This question has more than one correct answer.

What effect would hypernatremia have on the resting membrane potential (RMP)?