| hair cells, outer | Mechanoreceptors in the organ of corti. In mammals the outer hair cells are arranged in three rows which are further from the modiolus than the single row of inner hair cells. The motile properties of the outer hair cells may contribute actively to tuning the sensitivity and frequency selectivity of the cochlea. (12 Dec 1998) |
|---|---|
| hair cells, vestibular | Mechanoreceptors located in the acoustic maculae and the saemicircular canals that mediate the sense of balance, movement, and head position. The vestibular hair cells are connected to accessory structures in such a way that movements of the head displace their stereocilia. This influences the membrane potential of the cells which relay information about movements via the vestibular part of the acoustic nerve to the brainstem. (12 Dec 1998) |
| hair colour | Colour of hair or fur. (12 Dec 1998) |
| hair crosses | Crosslike figures formed by hairs growing from two directions that meet and then separate in a direction perpendicular to the original orientation. Synonym: hair crosses. (05 Mar 2000) |
| hair cycle | The cyclical phases of growth (anagen), regression (catagen), and quiescence (telogen) in the life of a hair. (05 Mar 2000) |
| hair diseases | Diseases affecting the orderly growth and persistence of hair. (12 Dec 1998) |
| hair disk | A richly innervated area of skin around a hair follicle, consisting of a thickened layer of epithelial cells in which ramify unmyelinated terminals of a single axon. (05 Mar 2000) |
| hair dyes | Dyes used as cosmetics to change hair colour either permanently or temporarily. (12 Dec 1998) |
| hair follicle | <dermatology> A tube-like opening in the epidermis where the hair shaft develops and into which the sebaceous glands open (13 Nov 1997) |
| hair grass | <botany> A grass with very slender leaves or branches; as the Agrostis scabra, and several species of Aira or Deschampsia. Source: Websters Dictionary (01 Mar 1998) |
| cuticle of hair | A layer of overlapping shingle-like cells that invest the hair cortex and serve to lock the hair shaft in its follicle. Synonym: cuticle of hair. Cuticula vaginae folliculi pili, cuticle of overlapping shingle-like cells lining the follicle of the hair. Synonym: cuticle of root sheath. (05 Mar 2000) |
| hair loss | Hair loss may be associated with aging, hormones (androgens) or genetic predisposition. The pattern of baldness in women is different from that of men. In women there is thinning of the hair all over the scalp, but the frontal hairline is maintained. The hair loss is usually permanent. Treatment has been successful with topical minoxidil in some cases. (13 Nov 1997) |
| hair papilla | Synonym: papilla pili. (05 Mar 2000) |
| hair preparations | Hair grooming and cleansing aids or other products meant for topical application to hair, usually human. They include sprays, bleaches, conditioners, rinses, shampoos, nutrient lotions, etc. (12 Dec 1998) |
| hair root | The part of a hair that is embedded in the hair follicle, its lower succulent extremity capping the dermal papilla pili in the deep bulbous portion of the follicle. Synonym: radix pili. (05 Mar 2000) |