Gland of Zeis Gland of Zeis Glands of Zeis are unilobar sebaceous glands located on the margin of the eyelid. The glands of Zeis service the eyelash. These glands produce an oily substance that is issued through the excretory ducts of the sebaceous lobule into the middle portion of the hair follicle. In the same area of the eyelid, near the base of the eyelashes are apocrine glands called the "glands of Moll". If eyelashes are not kept clean, conditions such as folliculitis may take place, and if the sebaceous gland becomes infected, it can lead to abscesses and styes. The glands of
Sealant Sealant Sealant is a substance used to block the passage of fluids through the surface or joints or openings in materials, a type of mechanical seal. In building construction "sealant" is sometimes synonymous with "caulking" and also serve the purposes of blocking dust, sound and heat transmission. Sealants may be weak or strong, flexible or rigid, permanent or temporary. Sealants are not adhesives but some have adhesive qualities and are called "adhesive-sealants" or "structural sealants". Sealants were first used in prehistory in the broadest sense as mud, grass and reeds to seal dwellings from the weather such as the daub