One of the functions of the endocrine system is controlling the body's growth and development. Affecting the function of various tissues, supporting reproductive functions, and regulating metabolism are functions of the endocrine system.
Endocrine organs are known as ductless glands because they have no ducts connecting them to specific body parts. The hormones they secrete are released directly into the bloodstream.
The endocrine system is made up of the following glands:
Pituitary, Hypothalamus, adrenal, parathyroid, thyroid, pineal and reproductive organs (ovaries and testes).
This gland is located deep inside the brain. It controls the activity of the endocrine system. The hypothalamus acts in cooperation between the brain and the pituitary gland which makes it the primary link between the endocrine and nervous system.
The pituitary gland
The pituitary gland is located at the base of the brain. It has a very important role in the body as it secretes hormones that regulate other endocrine glands. The pituitary gland has two sections (the anterior and posterior lobes). Each one has a separate function.
The anterior lobe controls the thyroid, adrenal and reproductive glands. It is responsible for controlling growth and milk production in women who are breast feeding. The hormones produced by the anterior lobe are:
Follicle-stimulating hormone (FSH )
The posterior lobe
The posterior lobe of the pituitary gland secretes antidiuretic hormones which controls the water balance in the body. It also produces oxytocin which influences muscle contractions during child birth and milk production.
The thyroid gland
The thyroid gland is located in the neck. It produces hormones when stimulated by the pituitary gland. The thyroid gland secretes thyroxine and three-iodothyronine that controls body growth and metabolism.
The parathyroid glands
The parathyroid glands are four glands found at the four corners of the thyroid gland. They secrete the hormone called parathyroid which controls the level of calcium in the blood.
The male and female reproductive organs (testes in males and ovaries in the female) produce hormones. The testes produces testosterone which brings about the physical male characteristics (muscular body, facial hair, deeper voice, etc.).
Ovaries produce oestrogen and progesterone which bring about the physical female characteristics (broad hips, breasts, menstrual cycle).
The adrenal glands are found on top of the kidneys. It secretes hormones which regulates metabolism, balance of water and salts and prepares the body to handle stress.
The adrenal gland is mostly known for producing adrenaline often called the "fight or flight" hormone. Adrenaline increases blood flow and heart rate to super charge the body to respond to danger.
The pineal gland
The pineal gland is found in the center of the brain. The pineal gland produces the hormone melatonin which regulates the wake and sleep cycle.
Although the pancreas has a digestive role it also has a hormonal function. It secretes insulin and glucagon which controls blood sugar levels.