Question: Assume your text provides an interesting explanation for the “dormitory effect”, in which women living (or sometimes working) together tend to synchronize their menstrual cycles. Gonadotropin releasing hormone is not the only hypothalamic hormone, of course, so we may wonder what other parts of the hypothalamo-hypophyseal portal system is responsive to a “living or working in a group” effect. Perhaps we can smell when others are “stressed” and it causes us to change our levels of cortisol by a mechanism similar to the “dormitory effect”. Explain how that pathway might work step-by-step, starting with the nose and ending with the adrenal cortex, and then describe a simple experiment to test the idea.

Question: The drug Nifedipine is mentioned in this chapter as a membrane calcium ion channel blocker, and it is used to relax the walls of blood vessels (effectively lowering high blood pressure). Explain step-by-step how blocking membrane calcium channels could have this effect, especially considering that smooth muscle has no troponin. Second, the drug is also used to slow down labor during childbirth, presumably by its action on the uterus. Would that work similarly to Nifedipine’s effect on blood vessel walls?

Question: Sometimes a person having heart problems will have an artificial pacemaker implanted, as described in your text. The procedure often leads to them feeling much better – but why? Why exactly were they feeling much worse before the operation, and why did the pacemaker help?