The primary role of endocrine glands in the body is to secrete hormones that regulate various physiological processes. These hormones act as chemical messengers, traveling through the bloodstream to target organs, influencing functions such as growth, metabolism, reproduction, and mood. Key glands include the pituitary, thyroid, and adrenal glands. Proper function of the endocrine system is critical for maintaining homeostasis, and imbalances can lead to various health issues, highlighting its importance in overall body regulation.