Membrane system within the cytoplasm of a eukaryotic cell (see eukaryote), important in the synthesis of proteins and lipids. The ER usually makes up more than half the membrane of the cell and is continuous with the outer membrane of the nuclear envelope (see nucleus). There are two distinct regions of ER: the rough ER, or RER (so called because of the protein-synthesizing ribosomes attached to it), and the smooth ER (SER), which is not associated with ribosomes and is involved in the synthesis of lipids and the detoxification of some toxic chemicals.

Learn more about endoplasmic reticulum (ER) with a free trial on Britannica.com.

Reticulum (reticle), is one of the minor southern constellations. It was introduced in the early 17th century by the astronomer Isaac Habrecht, who named it Rhombus. It was later renamed by Nicolas Louis de Lacaille to commemorate the reticle, which was a scientific instrument used to measure star positions.

Since it was introduced in the 18th century, there is no earlier mythology associated with it.

Notable Stars

• Epsilon Reticuli has an extrasolar planet.
• Zeta Reticuli is a pair of stars similar to the Sun. These stars gained some notoriety in ufology when they were alleged to be the home of an alien civilization. (See Betty and Barney Hill abduction.) Possibly as a consequence, it was chosen to be the locale of the movie Alien.

See also

• List of stars in Reticulum

References

Footnotes