Many adults living in the US become curious about doctor prescribed growth hormone replacement therapy when they begin to experience chronic symptoms, such as low energy, fatigue and low sex drive, that are frequently associated with your bodyâs declining growth hormone levels.
External, or exocrine, secretion is distinguished from internal, or endocrine, secretion. In external secretion the products elaborated by a gland are released into the external environment; the secretion first enters the glandular duct, from which it is discharged onto the surface of the body or into hollow organs.
The endocrine system is a control system of the human body much like the nervous system. The endocrine system produces chemical messages in the form of hormones, whereas the nervous system produces electrical messages.The endocrine system is made up of lots of specialised endocrine glands that secrete hormones into the bloodstream. Some of the major endocrine glands are shown on this diagram.he pituitary gland is known as the âmaster glandâ because its secretions control the activity of other endocrine glands. The activity of the pituitary gland is however controlled by the hypothalamus which as well as being an endocrine gland, is also part of the nervous system.