✪✪✪✪✪ http://www.theaudiopedia.com ✪✪✪✪✪ What is ENDOCRINE SYSTEM? What does ENDOCRINE SYSTEM mean? ENDOCRINE SYSTEM meaning – ENDOCRINE SYSTEM definition – ENDOCRINE SYSTEM explanation. Source: Wikipedia.org article, adapted under https://creativecommons.org/licenses/by-sa/3.0/ license. SUBSCRIBE to our Google Earth flights channel – https://www.youtube.com/channel/UC6UuCPh7GrXznZi0Hz2YQnQ The endocrine system is the collection of glands of an organism that secrete hormones directly into the circulatory system to be carried towards distant target organs. The phenomenon of biochemical processes’ serving to regulate distant tissues by means of secretions directly into the circulatory system is called endocrine signaling. The major endocrine glands include the pineal gland, pituitary gland, pancreas, ovaries, testes, thyroid gland, parathyroid gland, and adrenal glands. The endocrine system is in contrast to the exocrine system, which secretes its hormones to the outside of the body using ducts. The endocrine system is an information signal system like the nervous system, yet its effects and mechanism are classifiably different. The endocrine system’s effects are slow to initiate, and prolonged in their response, lasting from a few hours up to weeks. The nervous system sends information very quickly, and responses are generally short lived. In vertebrates, the hypothalamus is the neural control center for all endocrine systems. The field of study dealing with the endocrine system and its disorders is endocrinology, a branch of internal medicine. Special features of endocrine glands are, in general, their ductless nature, their vascularity, and commonly the presence of intracellular vacuoles or granules that store their hormones. In contrast, exocrine glands, such as salivary glands, sweat glands, and glands within the gastrointestinal tract, tend to be much less vascular and have ducts or a hollow lumen. In addition to the specialized endocrine organs mentioned above, many other organs that are part of other body systems, such as bone, kidney, liver, heart and gonads, have secondary endocrine functions. For example, the kidney secretes endocrine hormones such as erythropoietin and renin. Hormones can consist of either amino acid complexes, steroids, eicosanoids, leukotrienes, or prostaglandins. A number of glands that signal each other in sequence are usually referred to as an axis, for example, the hypothalamic-pituitary-adrenal axis. As opposed to endocrine factors that travel considerably longer distances via the circulatory system, other signaling molecules, such as paracrine factors involved in paracrine signalling diffuse over a relatively short distance.