EVERYDAY SCIENCE

Detailed explanation-1: -The endoplasmic reticulum (ER) is a network of membrane-enclosed tubules and sacs (cisternae) that extends from the nuclear membrane throughout the cytoplasm (Figure 9.1). The entire endoplasmic reticulum is enclosed by a continuous membrane and is the largest organelle of most eukaryotic cells.

Detailed explanation-2: -The ribosome that is synthesizing the protein is directly attached to the ER membrane. These membrane-bound ribosomes coat the surface of the ER, creating regions termed rough endoplasmic reticulum, or rough ER (Figure 12-36A).

Detailed explanation-3: -The endoplasmic reticulum is a network of membranes found throughout the cell and connected to the nucleus. It is of two types RER and SER. Rough ER (RER) is the endoplasmic reticulum attached to the ribosome and thus involves the formation and transportation of proteins.

Detailed explanation-4: -The general structure of the endoplasmic reticulum is a network of membranes called cisternae. These sac-like structures are held together by the cytoskeleton. The phospholipid membrane encloses the cisternal space (or lumen), which is continuous with the perinuclear space but separate from the cytosol.

Detailed explanation-5: -Endoplasmic reticulum (ER) is a system of membrane-lined channels found in all eukaryotic cells except mature erythrocytes. It constitutes more than 30 to 60 percent of total cell membranes. It provides protein and lipid to form the structure of cell membrane.