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.
Science Main Index. Hormones are chemical messengers that help regulate bodily functions. They are produced by glands in the body. In the digestive system, hormones regulate functions such as enzyme and gastric juice production used in the breakdown of fats, proteins, and carbohydrates.They also control the pace of muscle contractions moving food along the digestive tract.Read on to learn more about hormones, and their role in digestion.cience Main Index. Hormones are chemical messengers that help regulate bodily functions. They are produced by glands in the body. In the digestive system, hormones regulate functions such as enzyme and gastric juice production used in the breakdown of fats, proteins, and carbohydrates.