Answer: Antagonistic control.
- A Antagonistic control
- B Synergistic control
- C Permissive action
- D A feedback failure
Correct answer: A. Antagonistic control
Explanation: Insulin and glucagon act antagonistically - their opposite effects on blood glucose keep it within a narrow range.
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.