Answer: neck.
- A neck
- B abdomen
- C brain
- D chest
Correct answer: A. neck
Explanation: The thyroid gland lies in the neck, in front of the windpipe.
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.