Microvilli


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Microvilli

 

specialized outgrowths of the plasma membrane of epithelial cells in animals and man. Microvilli are 500–3,000 nanometers in length and their diameter ranges from 50 to 100 nm. There are several thousand microvilli in a single cell. Sometimes their arrangement is orderly, as in the striated (brushlike) edges of the epithelial cells of the small intestine, where the microvilli are about 20 nm from each other. Microvilli increase the cell surface. Cuticles in vertebrate animals also consist of microvilli.

References in periodicals archive ?
The desiccated corneal cells lack the microvilli and glycocalyx necessary to render the surface wettable and this will manifest as a decrease in tear breakup time.
Previous reports [42, 43] have shown that epithelial cell microvilli in particular are affected by lectin exposure, which initiates disruption and shedding of these membrane rich surface projections.
flavicincta the striated border is longer in the anterior midgut region, similar to that found in the stingless bees Trigona hypogea and Trigona spinipes, which have longer microvilli in their midgut region (Serrao & Cruz-Landim 1996b).
For epithelioid mesotheliomas these include very long, thin apical microvilli that do not have a glycocalyx, as opposed to the generally shorter microvilli of adenocarcinomas that usually do have a glycocalyx; perinuclear tonofilament bundles; the presence of basal lamina; and long desmosomes.
1996) hypothesized that even without accounting for increased surface area of villi and microvilli, intestinal surface area was likely to increase in fish kept in cooler water.
3] used transmission electron microscopy to demonstrate a reduced height of microvilli, presence of glycocalyceal bodies and an increased number of lysosomes.
The centrally located intestine measured 25 um in diameter, was laterally compressed, and was lined by columnar cells with microvilli and abundant cytoplasmic granules.
A lophotrochozoan affinity is hinted at by the construction of the teeth from apically directed fibres, which is suggestive of secretion by microvilli (see Butterfield 2008).
The small intestine is lined with villi and microvilli with a total surface area near that of a tennis court, for collecting nutrients by capillary action.
Epidermis on the dorsal surface of the fin rays is non-tuberculate, consisting of flattened hexagonal cells with well developed microvilli or microvillar ridges with an average of about one pore (presumably a mucus pore) for every two cells.
Notice that, in these cells (Figure 3B and D), the membranes are well preserved but there are fewer microvilli.
In previous studies, electron microscopic evaluation of renal cortex of PDTC, in combination with STZ treated animals' kidneys revealed that microvilli and basal foldings were similar to control group, and this confirms that cellular damage caused by iNOS may be partially suppressed by PDTC.