The role of the endocrine system is to help regulate and control the workings of the human body. It plays a critical role in metabolism, sexual development, and growth of humans. The endocrine system exerts its effect through hormones, which are chemical mediators produced by the endocrine glands that travel through the blood and affect the function of distant organs.
One important role of the endocrine system is to regulate the body’s metabolism. The thyroid gland can increase or decrease the overall activity level of the body, either ramping up the breakdown of substances needed for energy or decreasing the amount of energy used by the body. Hormones produced by the pancreas, including insulin and glucagon, affect how much glucose is available in the blood for use by the cells of the body. The thyroid gland and the endocrine glands of the pancreas working in concert thus regulate energy availability and use.
Another critical role of the endocrine system is to regulate the growth and development of the body. Growth hormone, produced by the pituitary, an organ located in the brain, helps mediate whether bone and muscle should be produced by the body. Although this hormone is more important during childhood, it continues to play an important role in the proper health of adults.
Reproduction and sexual maturity are also regulated by the endocrine system. Hormones — including estrogen and testosterone, important for the sexual development of women and men respectively — are considered mediators of the endocrine system. The pituitary makes hormones including follicle stimulating hormone and luteinizing hormone that in men regulate sperm production, and in women regulate the maturation and fertilization of eggs.
Perhaps one role of the endocrine system less well understood by many people is in maintaining the proper blood pressure. Hormones produced by the adrenal glands, which are located above the kidneys, help make sure that blood pressure is high enough to ensure that even parts of the body located far away from the heart obtain enough blood. These hormones regulate the amount of water, as well as the concentration of minerals, in the blood.
A different role of the endocrine system is to maintain the strength of the bones, and to ensure that there is enough calcium available in the body. The parathyroid gland makes a hormone that increases the concentration of calcium in the blood by taking it out of the bones. Other hormones work in the opposite way, using the calcium available in the body to build and strengthen the bones.