Endoplasmic reticulum
The endoplasmic reticulum (ER) is a system of abundant, intracellular unit membranes. Regions of the endoplasmic reticulum studded with ribosomes are called rough endoplasmic reticulum (RER), while regions lacking ribosomes are termed smooth endoplasmic reticulum (SER).
RER >
The RER consists of flattened, interconnected membranous sacs (cisterns) that are continuous with the nuclear envelope. RER possesses ribosomes for synthesis of proteins for export, membrane insertion and incorporation into lysosomes. Proteins synthesized by the ribosomes accumulate in the central space of the RER cisterns before being transported to the Golgi apparatus.
- Ribosomes on RER
The RER consists of flattened, interconnected membranous sacs (cisterns) that are continuous with the nuclear envelope. RER possesses ribosomes for synthesis of proteins for export, membrane insertion and incorporation into lysosomes. Proteins synthesized by the ribosomes accumulate in the central space of the RER cisterns before being transported to the Golgi apparatus.
Connection with nuclear envelope
The RER consists of flattened, interconnected membranous sacs (cisterns) that are continuous with the nuclear envelope. RER possesses ribosomes for synthesis of proteins for export, membrane insertion and incorporation into lysosomes. Proteins synthesized by the ribosomes accumulate in the central space of the RER cisterns before being transported to the Golgi apparatus.
SER >
SER consists of branched tubules of unit membranes that are continuous with the RER. SER lacks ribosomes and functions in lipid synthesis, detoxification and calcium storage.
