Question

Which of the following statements about the adrenal gland is correct?

• A. During stress, TSH stimulates the adrenal cortex and medulla to secrete acetylcholine.
• B. During stress, the alpha cells of islets secrete insulin and simultaneously the beta cells of the islets secrete glucagon.
• C. During stress, ACTH stimulates the adrenal cortex, and neurons of the sympathetic nervous system stimulate the adrenal medulla.
• D. At all times, the anterior portion secretes ACTH, while the posterior portion secretes Oxytocin.

Answer 1

The correct option is C

During stress, ACTH stimulates the adrenal cortex, and neurons of the sympathetic nervous system stimulate the adrenal medulla.

The pituitary gland produces the hormone ACTH, that stimulates the adrenal cortex. It stimulates secretion of glucocorticoids such as cortisol. ACTH is secreted in response to corticotropin-releasing hormone from the hypothalamus which is secreted in response to various types of stress. The adrenal medulla receives neural input from axons of the sympathetic division of the autonomic nervous system, and it secretes epinephrine and norepinephrine in response to stimulation by these axons. The actions of these hormones trigger “alarm” responses similar to those elicited by the sympathetic division, helping to prepare the body for “fight or flight”. Among the effects of these hormones are an increased heart rate, increased blood pressure, dilation of the bronchioles, elevation in blood glucose, and reduced blood flow to the skin and digestive organs. The actions of epinephrine released as a hormone supplement those of norepinephrine released as a sympathetic nerve neurotransmitter.