The dark pigment found in the skin, hair, and iris of the eye; its concentration determines the darkness of these tissues.

an iron-containing protein in red blood cells that transports oxygen, also known as [[血红蛋白|血紅蛋白|xue4 hong2 dan4 bai2]]

anthocyanidin, a type of natural pigment found in plants

bilirubin; any of several pigments found in bile, such as bilirubin or biliverdin

cytochrome; a class of hemoprotein found in the inner membrane of mitochondria that facilitates electron transport during cellular respiration

anthocyanin; a type of pigment found in plants used in biochemistry

any of a class of organelles in the cells of plants and algae, such as a [[叶绿体|葉綠體|ye4 lu:4 ti3]]

hemochromatosis; a genetic disorder where the body builds up too much iron