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How do the adrenal cortex and adrenal medulla differ?

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Diagram showing the locations of major human endocrine glands in male and female bodies, including pineal gland, hypothalamus, pituitary gland, parathyroid glands, thyroid gland, thymus, adrenal glands, pancreas, kidneys, testes, and ovaries. — Endocrine system The glands of the human endocrine system.

The adrenal cortex and adrenal medulla are the two distinct components of the adrenal gland, differing significantly in their embryological origins, structures, and functions.1

Adrenal Cortex

Comprising approximately 90 percent of the gland, the outer cortex is organized into three concentric zones: the zona glomerulosa, zona fasciculata, and zona reticularis. It functions by synthesizing steroid hormones from cholesterol, including aldosterone, cortisol, and adrenal androgens.2

Adrenal Medulla

The inner medulla makes up about 10 percent of the gland's weight and consists of chromaffin cells derived from the embryonic neural crest. Functioning as an integral part of the sympathetic nervous system, it acts as a neurohemal organ that releases dopamine, norepinephrine, and epinephrine into the circulation in response to nerve impulses.31

Would you like to know more about how these hormones specifically regulate the body's stress response?