A pea-sized gland under the brain that tells the thyroid, adrenals and reproductive organs what to do.
The chain of command
The hypothalamus signals the pituitary, which releases hormones like TSH, ACTH and growth hormone into the blood.
Evidence & sources
The pituitary gland makes hormones that control several other endocrine glands. Evidence: established. Known: Foundational physiology. Unknown: — Source: MedlinePlus (US National Library of Medicine), Pituitary Disorders (Current revision).