| bacterial outer membrane proteins | Proteins isolated from the outer membrane of bacteria. (12 Dec 1998) |
|---|---|
| outer membrane | The larger of the two membranes of a double membrane. (05 Mar 2000) |
| acrosomal cap | A collapsed membranous vesicle that covers the anterior part of the nucleus of the spermatozoon, derived from the acrosomal granule; the carbohydrate-rich substance of the cap is associated with hydrolytic enzymes that aid in sperm penetration of the zona pellucida of the ovum. Synonym: head cap. (05 Mar 2000) |
| acrosomal granule | The single glycoprotein rich granule within an acrosomal vesicle, which results from the coalescence of proacrosomal granule's. (05 Mar 2000) |
| acrosomal vesicle | A vesicle derived from the Golgi apparatus during spermiogenesis whose limiting membrane adheres to the nuclear envelope; together with the acrosomal granule within, it spreads in a thin layer over the pole of the nucleus to form the acrosomal cap. (05 Mar 2000) |
| rod outer segment | <ophthalmology, physiology> Major photoreceptor cell of vertebrate retina (about 125 million in a human eye). Columnar cells (about 40m long, 1m diameter) having three distinct regions: a region adjacent to and synapsed with, the neural layer of the retina contains the nucleus and other cytoplasmic organelles, below this is the inner segment, rich in mitochondria, that is connected through a thin neck (in which is located a ciliary body) to the outer segment. The outer segment largely consists of a stack of discs membrane infoldings that are incompletely separated in cones) that are continually replenished near the inner segment and that are shed from the distal end and phagocytosed by the pigmented epithelium. The membranes of the discs are rich in rhodopsin, the pigment that absorbs light. (03 Jul 1999) |
| rod outer segments | The portion of the retinal rod cell between the inner segment and the pigment epithelium layer of the retina. (12 Dec 1998) |
| 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) |
| outer cone fibre | Located between the inner segment and the cell body. (05 Mar 2000) |
| outer malleolus | The process at the lateral side of the lower end of the fibula, forming the projection of the lateral part of the ankle; the lateral malleolus is more inferiorly placed then the medial malleolus. Synonym: malleolus lateralis, external malleolus, extramalleolus, outer malleolus. (05 Mar 2000) |
| outer table of skull | The outer compact layer of the cranial bones. Synonym: lamina externa cranii. (05 Mar 2000) |
| the outer | Ovarian extremity of the oviduct. (05 Mar 2000) |
| adamantine membrane | The primary enamel cuticle, consisting of two extremely thin layers (the inner one clear and structureless, the outer one cellular), covering the entire crown of newly erupted teeth and subsequently abraded by mastication; it is evident microscopically as an amorphous material between the attachment epithelium and the tooth. Synonym: cuticula dentis, adamantine membrane, dental cuticle, membrana adamantina, Nasmyth's cuticle, Nasmyth's membrane, skin of teeth. (05 Mar 2000) |
| allantoid membrane | An embryonic diverticulum of the hindgut of reptiles, birds, and mammals; in man its blood vessels give rise to those of the umbilical cord. (12 Dec 1998) |
| alveolocapillary membrane | The pulmonary diffusion barrier. (05 Mar 2000) |