Adrenal Glands: Structure, Cortex & Medulla Explained

The adrenal glands are small, pyramid-shaped organs that sit on top of the kidneys.

Two Distinct Glands

• The structure of each adrenal gland is such that it is two distinct glands: the outside part, called the adrenal cortex, and the inside part, called the adrenal medulla.

Adrenal Cortex

• The structure of the adrenal cortex is three layers of cells called the zona glomerulosa, zona fasciculata, and zona reticularis.

Adrenal Medulla

• The adrenal medulla is surrounded by the adrenal cortex and is about 10 percent of the total adrenal gland, according to SUNY Downstate Medical Center.

Hormones

• The adrenal cortex produces hormones that affect the body's metabolism, chemicals in the blood, and some body characteristics. These hormones include corticosteroid hormones, aldosterone hormone, and androgen hormones. The adrenal medulla secretes epinephrine (adrenaline) and norepinephrine (noradrenaline).

Considerations

• The purpose of all adrenal hormones is to help us cope with stressful situations.