Cilia

‘Cilia’ is the plural form of Cilium, a Latin word. It refers to the edge of the eyelid, and much later to the eyelashes. So, the term came to refer to the fine hair like projection from cells, such as those in the respiratory tract. These sweep in unison and help to sweep away fluids and particles. Some single celled organisms use the rhythmical motion of Cilia for locomotion.Mammals have motile cilia. Motile cilia are usually present on a cell’s surface in large numbers and beat in coordinated waves. In humans, motile cilia are found in the lining of the trachea. Here, they sweep mucus and dirt out of the lungs. In female mammals, the beating of cilia in the Fallopian tubes moves the ovum from the ovary to the uterus.