reticulum

1. A fine network formed by cells, or formed of certain structures within cells or of connective tissue fibers between cells. 2. SYN: neuroglia. 3. The second compartment of the stomach of a ruminant, a comparatively small chamber communicating with the rumen; sometimes called the honeycomb because of the characteristic structure of its wall. [L. dim of rete, a net]

- agranular endoplasmic r. endoplasmic r. that is lacking in ribosomal granules; involved in synthesis of complex lipids and fatty acid s, detoxification of drugs, carbohydrate synthesis, and sequestering of Ca⁺⁺. SYN: smooth-surfaced endoplasmic r..

- Ebner r. a network of nucleated cells in the seminiferous tubules.

- endoplasmic r. (ER) the network of cytoplasmic tubules or flattened sacs (cisternae) with (rough ER) or without (smooth ER) ribosomes on the surface of their membranes in eukaryotes. SYN: endomembrane system.

- Golgi internal r. SYN: Golgi apparatus.

- granular endoplasmic r. endoplasmic r. in which ribosomal granules are applied to the cytoplasmic surface of the cisternae; involved in the synthesis and secretion of protein via membrane-bound vesicles to the extracellular space. SYN: chromidial substance, ergastoplasm, rough-surfaced endoplasmic r..

- Kölliker r. SYN: neuroglia.

- rough-surfaced endoplasmic r. SYN: granular endoplasmic r..

- sarcoplasmic r. the endoplasmic r. 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.

- smooth-surfaced endoplasmic r. SYN: agranular endoplasmic r..

- stellate r. a network of epithelial cells disposed in a fluid-filled compartment in the center of the enamel organ between the outer and inner enamel epithelium.

- trabecular r. SYN: trabecular tissue of sclera.

- r. trabeculare sclerae [TA] SYN: trabecular tissue of sclera.

- trans-Golgi r. that part of the Golgi apparatus that takes newly processed proteins and delivers them to secretory vesicles that will fuse with other biomembranes ( E.G., the plasma membrane).

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re·tic·u·lum ri-'tik-yə-ləm n, pl -la -lə

1) the second compartment of the stomach of a ruminant in which folds of the mucous membrane form hexagonal cells called also honeycomb compare ABOMASUM, OMASUM, RUMEN

2) a reticular structure: NETWORK: as

a) the network of interstitial tissue composed of reticular fibers called also reticular tissue

b) the network often visible in fixed protoplasm both of the cell body and the nucleus of many cells

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n.

a network of tubules or blood vessels. See endoplasmic reticulum, sarcoplasmic reticulum.

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re·tic·u·lum (rə-tikґu-ləm) pl. reticґula [L., dim. of rete net] 1. a small network, especially one within a cell. 2. reticular tissue. 3. the second stomach of a ruminant; its mucous membranes are covered with many small pockets. Called also honeycomb.