The endocrine system is made up of glands that make hormones. Hormones are the body's chemical messengers that carry information and instructions from one set of cells to another. This system influences almost every cell, organ, and function of our bodies. Endocrine glands release hormones into the bloodstream, which allows the hormones to travel to cells in other parts of the body. The endocrine hormoes help control mood, growth, and development, the way our organs work, metabolism (all of the chemical reactions within your body), and reproduction. It also regulates how much of each hormone is released, which depends on the levels of hormones already in the blood, or on levels of other substances in the blood, like calcium. Many things afect hormone levels, such as stress, infection, and changes in the balance of fliud and minerals in blood. Having too little or too much of any hormone can harm the body. The parts endocrine system are:
The hypothalamusis the lower central part of the brain, which links the endocrine system with the nervous system. Nerve cells in the hypothalamus make chemicals that control the release of hormones secreted from the pituitary gland. The hypothalamus gathers information sensed by the brain and sends it to the pituitary. This information influences the hormones that the pituitary makes and releases. The pituitary gland is at the base of the brain, and is no bigger than a pea. Despite its small size, the pituitary is often called the "master gland." The hormones it makes control many other endocrine glands.
Here are all of the main organ systems of the human body and some info about them: