Reticulum(redirected from endoplasmic reticulum (1))
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Reticulum(ri-tik -yŭ-lŭm) (Net) A small constellation in the southern hemisphere near the Large Magellanic Cloud, the brightest stars being one of 3rd magnitude and some of 4th magnitude. Abbrev.: Ret; genitive form: Reticuli; approx. position: RA 4h, dec –60°; area: 114 sq deg.
a constellation in the southern sky, the brightest star of which has a visual stellar magnitude of 3.3. Reticulum is not visible from the USSR.
the second stomach of ruminants, located between the rumen and the omasum. The mucous membrane of the reticulum is covered with numerous tiny horny tubercles and forms rather high (8–12 mm) nonstraightening but loose folds in the form of four- to six-sided cells.
The reticulum usually does not have glands, although in Tylopoda, including camels and llamas, its walls contain cardial glands, whose ducts open on the bottom of deep cells. The reticulum communicates with the rumen, esophagus, and omasum. The esophageal groove passes from the esophageal aperture along the wall of the reticulum into the omasum. In the reticulum, food is moistened and undergoes mechanical and preliminary chemical processing, which is effected by the bacteria and protozoans (infusorians) that inhabit the reticulum. The energetic contractions of the musculature of the reticular walls and the movements of the muscosal folds cause finely masticated fodder to be separated from larger fodder particles and to enter the omasum, while the coarse particles pass back into the rumen.