Which type of glands release hormones into the bloodstream?

Endocrine glands are specifically designed to secrete hormones directly into the bloodstream. This allows the hormones to travel throughout the body and exert their effects on various organs and tissues, regulating numerous physiological processes such as metabolism, growth, reproduction, and mood. Unlike exocrine glands, which release their substances through ducts to external surfaces or into cavities (such as sweat glands and salivary glands), endocrine glands operate without ducts, ensuring a direct delivery system for hormones into the circulation.

Lymphatic glands primarily refer to structures associated with the lymphatic system, such as lymph nodes, which do not release hormones but instead are involved in immune function. Digestive glands, while they secrete substances that aid in digestion, do not release hormones into the bloodstream either; they typically have ducts leading to the digestive tract. Therefore, the defining characteristic of endocrine glands is their role in hormone secretion into the circulatory system, making them crucial for maintaining homeostasis in the body.