Internal control of the body is directed by two systems: the nervous system and the endocrine system The endocrine system is made up of a series of glands called endocrine glands, it releases chemicals into the blood stream. The glands are found throughout the body, most of them are controlled by the pituitary gland, which is the master gland. The pituitary gland is controlled by the hypothalamus, that is a part of the brain. The endocrine system controls the body, it helps growth, digestion, parturition, and lactation. The hormones are created from your gland, they go into the blood stream and then goes to the target cell, which is the cell that contains a receptor, which is the building site for creating more cells, or to increase production.
There is a system called the negative feedback control, which determines the amount of hormones you need in your body. Information regarding the hormone level or its effect on the target tissue is fed back usually to the hypothalamus or pituitary gland, to regulate the gland’s production of the hormone. There are two kinds of hormones, one if called the steroid hormones and another is called the amino acid hormones. The steroid hormones are made from lipids, they bind to the receptor in the cell and make them produce protein. The amino acid hormones are made from amino acids, they bind to the receptors and control what goes on inside the cell.
There are many types of hormones. One is the thyroid gland, which is located in the neck. It produces two hormones called the calcitonin that controls blood calcium levels and another is called the thyroxin that control cell metabolism The next gland is located in the kidney called the adrenai gland, this gland produces glucacorticoids, which mobilize body energy sources and have an antiflammationary action. Another hormone it makes is mineralocorticoids, which control salt and water balance in the body, and finally epinephrine, which increases the strength of heart contractions and increases blood sugar. Another part of the kidney produces rennin and angiotensin that controls blood pressure levels. The pancreas that is located near the small intestine produces insulin and glucagons, which controls blood sugar level. Another kind of hormone is produced inside the digestive tract called secretin and gastrin, which both stimulate secretion of digestive juice. The final hormones are the sex hormones, the female is the ovary, which produces estragens, which stimulate and maintain female sex characteristics. Progesterone, which is required to maintain pregnancy, and finally realize that, releases pelvic cartilage and ligaments for parturition. The male sex hormone is the testes, that produce testosterone also called androgens – which stimulates and maintains male sec characteristics.
