Answer: Endocrine gland.
- A Endocrine gland
- B Salivary gland
- C Exocrine gland
- D Sebaceous gland
Correct answer: A. Endocrine gland
Explanation: Endocrine glands are ductless glands that secrete hormones directly into the blood, which then reach target organs throughout the body.
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.