However, the red-yellow pheomelanin is believed to cause the warm, golden, or auburn tones found in some types of brown hair. The range of colors produced by melanins is limited to shades of yellow, brown, red, and black. Grey hairs contain only a few melanin granules, spread out through the hair.
Hormones are your body's chemical messengers. They travel in your bloodstream to tissues or organs. Endocrine glands, which are special groups of cells, make hormones. The major endocrine glands are the pituitary, pineal, thymus, thyroid, adrenal glands, and pancreas. In addition, men produce hormones in their testes and women produce them in their ovaries.
Parts of the Endocrine System. Hormones. Hormones are chemicals that control specific biological functions. They are made in your endocrine glands, secreted in small amounts directly into your bloodstream, and travel to other organs where they induce an action in the organâs cells.The Major Glands of the Endocrine System. Hypothalamus.he hypothalamusâ âreleasingâ hormones regulate the secretion of other hormones in your pituitary gland, which in turn affects other endocrine glands in your body. The hypothalamusâ âinhibitingâ hormones, as the name implies, turns off the secretion of some of the hormones released from the pituitary.