Which body system produces, stores, and secretes hormones carried by the circulatory system?

• A. Exocrine System
• B. Endocrine System
• C. Nervous System
• D. Respiratory

Answer: (B)

Hormones are chemical messengers produced by the endocrine glands and released directly into the bloodstream. The endocrine system stores these hormones in secretory cells and then secretes them into the circulatory system, allowing them to travel to distant target organs that have receptors for each hormone. This setup explains how the body coordinates processes like metabolism, growth, and stress responses over longer timescales. In contrast, exocrine glands release substances through ducts to surfaces, the nervous system uses nerve impulses for rapid signaling, and the respiratory system handles gas exchange.