Why are hormones important
Chemicals secreted by a group of particular cells or a gland in one section of the body, that affect the target cells which are located in a different part within the body in order to convey some sort of message are called hormones. The target cell responds by acting as a receptor for that particular hormone and thus a combination between the protein of the receptor cell and the hormone is created in order to initiate a signal transduction which of course results in the typical cell-specific reaction. There are a number of glands and cells in the human body that secrete hormones and each have specific receptor cells and thus induce specific reactions within the body.
Hormones induce, regulate and control almost all bodily functions and it is not an exaggeration to say that most disorders and many diseases result from hormonal imbalance. Although hormones are not produced by endocrine glands alone, the endocrine glands like the pituitary gland, the pancreas, the adrenalin glands, the thyroid, the parathyroid and the gonads are chiefly responsible for the hormonal secretions within the body.
Proper secretion of Serotonin, released by the GI tract is largely essential for maintaining a healthy appetite and keeping sleeping or mood disorders at bay. Triiodothyronine and thyroxine are both released by the thyroid gland. Triiodothyronine is mostly responsible for affecting the basal metabolic rate and protein synthesis, and while thyroxine also does the same, it is not as effective as Triiodothyronine. Vasopressin released by the posterior portion of the pituitary gland helps in kidney functions as well as monitoring vasoconstriction and releasing corticotropin in the anterior portion of the pituitary. Dopamine is a hormone that is released by both the hypothalamus and the kidney, but it affects the pulse rate and the blood pressure as well as controlling prolactin and TRH secretions from the anterior pituitary gland depending on its origin. A very important hormone released by the thyroid gland is calcitonin, necessary for bone construction and bone density.
The above examples are not enough to elaborate all the important functions that the hormones serve in our body and their effects on various organs, but it should give one an idea on how important hormones are in affecting, controlling and maintaining vital bodily functions.