Parathyroids: Attached to the thyroid are four tiny glands that work together called the parathyroids pronounced: par-uh-THY-roydz. They release parathyroid hormone, which controls the level of calcium in the blood with the help of calcitonin pronounced: kal-suh-TOE-nin , which the thyroid makes. The adrenal glands have two parts, each of which makes a set of hormones and has a different function:. Pineal: The pineal pronounced: pih-NEE-ul body, also called the pineal gland, is in the middle of the brain.
It secretes melatonin pronounced: meh-luh-TOE-nin , a hormone that may help regulate when you sleep at night and when you wake in the morning. Reproductive Glands: The gonads are the main source of sex hormones. Most people don't realize it, but both guys and girls have gonads.
In guys the male gonads , or testes pronounced: TES-teez , are in the scrotum. They secrete hormones called androgens pronounced: AN-druh-junz , the most important of which is testosterone pronounced: tess-TOSS-tuh-rone. These hormones tell a guy's body when it's time to make the changes associated with puberty, like penis and height growth, deepening voice, and growth in facial and pubic hair. Working with hormones from the pituitary gland, testosterone also tells a guy's body when it's time to make sperm in the testes.
A girl's gonads , the ovaries pronounced: OH-vuh-reez , are in her pelvis. Estrogen is involved when a girl starts puberty. During puberty, a girl will have breast growth, start to accumulate body fat around the hips and thighs, and have a growth spurt. Estrogen and progesterone are also involved in the regulation of a girl's menstrual cycle. These hormones also play a role in pregnancy. Pancreas: The pancreas pronounced: PAN-kree-us makes insulin pronounced: IN-suh-lin and glucagon pronounced: GLOO-kuh-gawn , which are hormones that control the level of glucose , or sugar, in the blood.
Insulin helps keep the body supplied with stores of energy. The body uses this stored energy for exercise and activity, and it also helps organs work as they should.
Reviewed by: Larissa Hirsch, MD. Larger text size Large text size Regular text size. What Is the Endocrine System? Exocrine glands Functions of the endocrine system How hormones work Endocrine glands and organs Problems of the endocrine system Where to get help Things to remember. Exocrine glands An exocrine gland, unlike an endocrine gland, is a gland that secretes substances electrolytes, proteins or enzymes straight to a target site via ducts or tube.
Some examples include: Salivary glands Sweat glands Sebaceous glands The pancreas. Functions of the endocrine system Some of the roles of the endocrine system include: Growth Repair Sexual reproduction Digestion Homeostasis constant internal balance. Endocrine glands and organs The main glands and organs of the endocrine system include: Pituitary gland — is inside the brain. It oversees the other glands and keeps hormone levels in check. The pituitary gland is also connected to the nervous system through part of the brain called the hypothalamus.
Thyroid gland — sits in the neck at the front of the windpipe. It releases thyroid hormone T4 and T3 which is required for metabolism and body homeostasis. It is controlled by TSH which is produced by the pituitary gland through a feed-back loop. Parathyroid gland — there are usually four parathyroid glands which lie alongside the thyroid gland. The parathyroid gland is involved in calcium, phosphate and vitamin D regulation.
Adrenal glands — there are two adrenal glands which sit on top of each kidney. They make a number of different hormones. The outside part of the gland adrenal cortex makes cortisol, aldosterone and sex hormones. The centre of the adrenal gland adrenal medulla makes adrenaline. Adrenaline is an example of a hormone that is under the control of the nervous system. Pancreas — an organ of digestion which is inside the abdomen. It makes insulin, which controls the amount of sugar in the bloodstream.
It also makes other hormones such as glucagon and somatostatin. Ovaries — are inside the female pelvis. They make female sex hormones like oestrogen. Testes — they hang in the male scrotal sack. They make male sex hormones like testosterone. Other lesser known endocrine organs include: Adipose tissue fat tissue — is recognised to be metabolically important. It releases hormones such as leptin, which affect appetite, and is also a site of oestrogen production.
Insulin also acts on adipose tissue. Kidneys — produce erythropoietin EPO which stimulates red blood cell production, produce renin which is needed for blood pressure regulation and produce the active form of Vitamin D 1—25 dihydroxy vitamin D3 Gut — an increasing number of hormones in the gut are being researched and being understood to effect metabolism and appetite. Included are glucagon-like peptide 1 GLP—1 , ghrelin which stimulates appetite, and somatostatin.
These glands include the sweat, sebaceous , and mammary glands and, the glands that secrete digestive enzymes. The endocrine glands do not have ducts to carry their product to a surface. They are called ductless glands. The word endocrine is derived from the Greek terms "endo," meaning within, and "krine," meaning to separate or secrete.
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