AEMCA Practice Exam

From where are epinephrine and norepinephrine released?

1. Brain cortex

2. Adrenal medulla

3. Pituitary gland

4. Spinal cord

The correct answer is: Adrenal medulla

Epinephrine and norepinephrine are hormones and neurotransmitters that are primarily released from the adrenal medulla, which is the inner part of the adrenal glands located on top of each kidney. The adrenal medulla is part of the body's sympathetic nervous system and plays a crucial role in the "fight or flight" response, releasing these catecholamines in response to stress, which leads to increased heart rate, blood flow to muscles, and energy production. The adrenal medulla synthesizes these hormones from tyrosine and releases them into the bloodstream, where they have widespread effects on various target organs. This release is vital for preparing the body to respond rapidly to threatening situations. The other choices do not serve as the primary source for these specific hormones. The brain cortex is associated with higher cognitive functions and does not directly release epinephrine or norepinephrine. The pituitary gland primarily produces different hormones that regulate other endocrine glands, while the spinal cord is involved in reflexes and nerve signal transmission but is not responsible for producing these hormones. Thus, the correct answer accurately identifies the source of epinephrine and norepinephrine as the adrenal medulla.