Tulane University defines an ore as a body of material from which one or more valuable substances can be extracted. For example, bauxite ore is mined and refined to extract aluminum.
root sheath the epidermic layer of a hair follicle. sheath of Schwann neurilemma. synovial sheath synovial membrane lining the cavity of a bone through which a tendon moves. tendon sheath a lubricated fibrous or synovial layer of tissue in which the tendon is housed and through which it moves.
The word hair usually refers to two distinct structures: 1  the part beneath the skin, called the hair follicle, or, when pulled from the skin, the bulb. 2  the shaft, which is the hard filamentous part that extends above the skin surface.air growth begins inside the hair follicle. The only living portion of the hair is found in the follicle. The hair that is visible is the hair shaft, which exhibits no biochemical activity and is considered dead.