The endocrine system is the second organ system that functions in communication and control and integrates the functions of other organ systems throughout the human body.

The endocrine system has the following primary functions: digestive and metabolic. Unlike the nervous system, the endocrine system does not necessarily communicate rapidly with other organ systems. The endocrine system contains glands that secrete hormones, which travel to target cells. The circulatory system is the primary means of transport of hormones throughout the body. The endocrine system has hormones that act as agonists and antagonists. Most agonistic and antagonistic hormones function via negative feedback mechanisms. Negative feedback involves the presence of one synergistic hormone signaling another not to be released. The glands of the endocrine system are widespread throughout the body. The nervous and endocrine systems often work in concert with one another.

The endocrine glands (pituitary, thyroid, pancreas and thymus) produce hormones that are released into the
bloodstream, circulate through the body and reach receptors in the cells and influence cellular metabolism.
Hormones exert major influences on the growth and development of babies bodies and control babies internal environment.

• The pituitary gland directs all of the physical functions of the body and activates the production of growth hormones. It is a gland just 4 mm in size sitting just below the hypothalamus at the base of the brain. From the third month in pregnancy, it sends growth hormones to all the body’s cells. As babies develop, the pituitary gland stimulates cell division and DNA formation.
• The thyroid is a small butterfly-like shaped gland positioned in the neck region just below the larynx. Controlled by the pituitary, it produces thyroxine that promotes growth and development especially of the bones, teeth and brain. The thyroid regulates the general metabolism of the body.
• The pancreas grows rapidly in a baby’s abdomen during the first year, from 3-5g at birth to over 10 g. The function of the pancreas is to secrete an alkaline juice to aid with the digestion of food, as well as glucagon and insulin, to maintain blood glucose levels.