ANATOMY

Detailed explanation-1: -The endomembrane system (endo-= “within”) is a group of membranes and organelles in eukaryotic cells that works together to modify, package, and transport lipids and proteins.

Detailed explanation-2: -The ER has a central role in lipid and protein biosynthesis. Its membrane is the site of production of all the transmembrane proteins and lipids for most of the cell’s organelles, including the ER itself, the Golgi apparatus, lysosomes, endosomes, secretory vesicles, and the plasma membrane.

Detailed explanation-3: -The Golgi apparatus is a central intracellular membrane-bound organelle with key functions in trafficking, processing, and sorting of newly synthesized membrane and secretory proteins and lipids. To best perform these functions, Golgi membranes form a unique stacked structure.

Detailed explanation-4: -Protein folding in the ER. The molecular chaperone BiP binds to polypeptide chains as they cross the ER membrane and facilitates protein folding and assembly within the ER.

Detailed explanation-5: -Endoplasmic reticulum (ER) is known as the maze of folded membranes where proteins and lipids are produced. The ER is a complex organelle composed of membranous flattened sacs, cylinders, and vesicles.