Answer: adrenal gland.
- A adrenal gland
- B thyroid gland
- C pituitary gland
- D pancreas
Correct answer: A. adrenal gland
Explanation: The adrenal glands sit on top of the kidneys.
The hypothalamus releases hormones that direct the pituitary, which releases its own trophic hormone to a target gland; that gland's hormone output then feeds back (dashed lines) to suppress both the pituitary and hypothalamus once levels are sufficient - a self-correcting loop running the entire endocrine system.
Concept context
The endocrine glands, hormone classification and mechanism of action, and negative feedback regulation.