"The endocrine system is a messenger system in an organism comprising feedback loops of hormones that are released by internal glands directly into the circulatory system and that target and regulate distant organs."
The study of the glands and organs that produce hormones and regulate bodily functions.
Endocrine glands: Endocrine glands are specialized glands that produce and release hormones directly into the bloodstream which then act on target organs.
Hormones: Hormones are chemical messengers that are produced and released by endocrine glands into the bloodstream, where they travel to specific organs and tissues to regulate various physiological processes such as metabolism, growth, and reproduction.
Feedback mechanisms: Feedback mechanisms are systems that regulate hormone production and release through a complex network of signals between the endocrine glands, target organs, and the brain. There are two types of feedback mechanisms, positive feedback and negative feedback.
Pituitary gland: The pituitary gland, also known as the "master gland," is located at the base of the brain and controls the activity of other endocrine glands. It produces and releases many important hormones, such as growth hormone, thyroid-stimulating hormone, and adrenocorticotropic hormone.
Thyroid gland: The thyroid gland, located in the neck, produces hormones that regulate metabolism, growth, and development. It produces the hormones thyroxine (T4) and triiodothyronine (T3).
Adrenal glands: The adrenal glands, located on top of the kidneys, produce hormones such as cortisol, aldosterone, and adrenaline (epinephrine) that help regulate metabolism, blood pressure, and the body's response to stress.
Pancreas: The pancreas is both an exocrine and an endocrine gland. The endocrine cells of the pancreas produce hormones such as insulin and glucagon that regulate blood sugar levels.
Reproductive hormones: Reproductive hormones such as testosterone, estrogen, progesterone, and follicle-stimulating hormone are produced by the gonads (testes in males and ovaries in females) and regulate the development and function of reproductive organs and secondary sex characteristics.
Parathyroid gland: The parathyroid glands, located next to the thyroid gland, produce parathyroid hormone (PTH) which regulates calcium and phosphate levels in the blood.
Pineal gland: The pineal gland, located in the brain, produces melatonin that helps regulate sleep-wake cycles and circadian rhythms.
Endocrine disorders: Endocrine disorders occur when the production, secretion, or signaling of hormones is disrupted, leading to a variety of conditions such as diabetes, hypothyroidism, hyperthyroidism, and adrenal insufficiency.
Pharmacology: Pharmacology is the study of drugs and their effects on the body. Many drugs are designed to target and modify the activity of specific endocrine hormones and their receptors.
Endocrine surgery: Endocrine surgery is a specialized field of surgical medicine that focuses on the diagnosis and treatment of diseases of the endocrine system, such as thyroid cancer and adrenal tumors.
Imaging techniques: A variety of imaging techniques such as ultrasound, CT scan, MRI, and PET scan can be used to visualize the structure and function of endocrine glands and organs in the body.
Pineal gland: Located in the brain, secretes melatonin which regulates sleep/wake cycle.
Pituitary gland: Located at the base of the brain, secretes various hormones that control other endocrine glands.
Thyroid gland: Located in the neck, secretes hormones that regulate metabolism.
Parathyroid gland: Located on the thyroid gland, secretes hormone that regulates calcium balance.
Adrenal gland: Located on top of the kidneys, secretes various hormones involved in the fight/flight response, such as adrenaline and cortisol.
Pancreas: Located behind the stomach, secretes insulin and glucagon, which regulate blood sugar levels.
Ovary: In females, secretes estrogen and progesterone, which regulate the menstrual cycle and fertility.
Testes: In males, secretes testosterone, which regulates secondary sex characteristics and fertility.
Thymus: In the chest, plays a role in the immune system by producing T-cells.
Placenta: In pregnant females, secretes hormones that support the developing fetus.
"In vertebrates, the hypothalamus is the neural control center for all endocrine systems."
"The major endocrine glands in humans are the thyroid, parathyroid, pituitary, pineal, and adrenal glands, and the (male) testes and (female) ovaries."
"The hypothalamus, pancreas, and thymus also function as endocrine glands, among other functions."
"One of the most important functions of the hypothalamus... is to link the endocrine system to the nervous system via the pituitary gland."
"Many other organs that are part of other body systems have secondary endocrine functions, including bone, kidneys, liver, heart, and gonads."
"Hormones can be amino acid complexes, steroids, eicosanoids, leukotrienes, or prostaglandins."
"Endocrine glands have no ducts, are vascular, and commonly have intracellular vacuoles or granules that store their hormones."
"The study of the endocrine system and its disorders is known as endocrinology."
"Glands that signal each other in sequence are often referred to as an axis, such as the hypothalamic–pituitary–adrenal axis."
"For example, the kidney secretes the endocrine hormone erythropoietin."
"Contrastingly, 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."
"For example, the kidney secretes the endocrine hormone erythropoietin."
"(The hypothalamus and pituitary glands are organs of the neuroendocrine system.)"
"One of the most important functions of the hypothalamus... is to link the endocrine system to the nervous system."
"The hypothalamus and pituitary glands are organs of the neuroendocrine system."
"The endocrine system is a messenger system in an organism comprising feedback loops of hormones."
"Hormones that are released by internal glands directly into the circulatory system."
"The (male) testes and (female) ovaries."
"Paracrine signaling between cells over a relatively short distance."