Search results
Results from the WOW.Com Content Network
Stereocilia (or stereovilli or villi) are non-motile apical cell modifications. They are distinct from cilia and microvilli , but are closely related to microvilli. They form single "finger-like" projections that may be branched, with normal cell membrane characteristics.
Resembling hair-like projections, the stereocilia are arranged in bundles of 30–300. [3] Within the bundles the stereocilia are often lined up in several rows of increasing height, similar to a staircase. At the core of these hair-like stereocilia are rigid cross-linked actin filaments, which can renew every
Microvilli (sg.: microvillus) are microscopic cellular membrane protrusions that increase the surface area for diffusion and minimize any increase in volume, [1] and are involved in a wide variety of functions, including absorption, secretion, cellular adhesion, and mechanotransduction.
The hair bundle is composed of stiff microvilli called stereocilia and is involved with mechanoreception of sound waves. Stereocilia cells generate an electrical response to the vibrations of sound waves, crucial for normal hearing. This gene is part of a tandem duplication on chromosome 15; the second copy is a pseudogene.
Pseudostratified columnar epithelia with stereocilia are located in the epididymis. Stereocilia of the epididymis are not cilia because their cytoskeleton is composed of actin filaments, not microtubules. [3] They are structurally and molecularly more similar to microvilli than to true cilia. [dubious – discuss]
The reason for this difference is the orientation of the macula in the two organs. The utricular macula lie horizontal in the utricle, while the saccular macula lies vertical in the saccule. Every hair cell in these sensory beds consist of 40-70 stereocilia and a kinocilium . [ 2 ]
Tracheal respiratory epithelium showing cilia and much smaller microvilli on non-ciliated cells in scanning electron micrograph. Mammals also have motile cilia or secondary cilia that are usually present on a cell's surface in large numbers (multiciliate), and beat in coordinated metachronal waves . [ 40 ]
The stereocilia are oriented by the striola, a curved ridge that runs through the middle of the macula; in the saccule they are oriented away from the striola [2] The tips of the stereocilia and kinocilium are embedded in a gelatinous otolithic membrane. This membrane is weighted with protein-calcium carbonate granules called otoliths, which ...