Category: D

A major constituent of pulmonary surfactant.  

A topical sunscreen that blocks ultraviolet A and B.  

A compound having two oxygen atoms per molecule.  

Producing two ova in the same ovarian cycle.  

A genus of yams, a potato-like root vegetable used in many cultures as a source of dietary carbohydrates. There are approx. 150 species. Dioscorea villosa, the wild yam, is used as a source of topically applied cosmetics and plant-derived steroids.  

The science of light refraction. The field of optics that specializes in the study of light refraction.  

The determination of refraction and accommodation of the eye.  

A device for measuring ocular refraction.  

A lack of interest in personal cleanliness or cleanliness of the home, usually occurring in elderly individuals who live alone. Affected persons usually are undernourished but not necessarily from poverty. This condition occurs in all socioeconomic circumstances. It may be associated with excessive saving of items, e.g., old newspapers; social retreat; and rejection of assistance.…

A genus of roundworms found in dogs but rarely in humans.