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1. a small network, especially a protoplasmic network in cells.
2. reticular tissue.
agranular reticulum smooth-surfaced endoplasmic reticulum.
endoplasmic reticulum an ultramicroscopic organelle of nearly all higher plant and animal cells, consisting of a system of membrane-bound cavities in the cytoplasm, occurring in two types: granular or rough-surfaced, bearing large numbers of ribosomes on its outer surface, and agranular or smooth-surfaced.
granular reticulum rough-surfaced endoplasmic reticulum.
sarcoplasmic reticulum a form of agranular reticulum in the sarcoplasm of striated muscle, comprising a system of smooth-surfaced tubules surrounding each myofibril.
the agranular endoplasmic reticulum of skeletal and cardiac muscle; the complex of vesicles, tubules, and cisternae forming a continuous structure around striated myofibrils, with a repetition of structure within each sarcomere.
The form of endoplasmic reticulum found in striated muscle fibers.
Etymology: Gk, sarx + plassein, to mold; L, reticulum, little net
a network of tubules and sacs in skeletal muscle fibers that plays an important role in muscle contraction and relaxation by releasing and storing calcium ions. This network is analogous, but not identical, to the endoplasmic reticulum of other cells.
sar·co·plas·mic re·tic·u·lum(sahr'kō-plaz'mik rĕ-tik'yū-lŭm)
The endoplasmic reticulum of skeletal and cardiac muscle; the complex of vesicles, tubules, and cisterns forming a continuous structure around striated myofibrils, with a repetition of structure within each sarcomere.