Endocrine Glands

Free Response

What does aldosterone regulate, and how is it stimulated?


The main mineralocorticoid is aldosterone, which regulates the concentration of ions in urine, sweat, and saliva. Aldosterone release from the adrenal cortex is stimulated by a decrease in blood concentrations of sodium ions, blood volume, or blood pressure, or an increase in blood potassium levels.

The adrenal medulla contains two types of secretory cells, what are they and what are their functions?


The adrenal medulla contains two types of secretory cells, one that produces epinephrine (adrenaline) and another that produces norepinephrine (noradrenaline). Epinephrine is the primary adrenal medulla hormone accounting for 75–80 percent of its secretions. Epinephrine and norepinephrine increase heart rate, breathing rate, cardiac muscle contractions, and blood glucose levels. They also accelerate the breakdown of glucose in skeletal muscles and stored fats in adipose tissue. The release of epinephrine and norepinephrine is stimulated by neural impulses from the sympathetic nervous system. These neural impulses originate from the hypothalamus in response to stress to prepare the body for the fight-or-flight response.

How would damage to the posterior pituitary gland affect the production and release of ADH and inhibiting hormones?


Damage to the posterior pituitary gland would prevent the release of ADH and oxytocin into the body. However, the hypothalamus’s ability to produce ADH would not be affected. The hypothalamus would also still be able to produce and release inhibiting hormones to regulate the anterior pituitary.