Precursors to S·R·E·B·P·s are found on this structure, where they are bound to S·C·A·P. Stress in this structure causes cleavage of A·T·F·6. This structure produces membrane lipids such as phospha·tidyl·choline and is responsible for the synthesis of cholesterol. Stress in this structure induces U·P·R, which degrades misfolded proteins. This structure stores calcium ions, (10[1])and is the origin of vesicles that transport proteins to the Golgi (10[2])body. (-5[1])One subtype of this structure contains ribosomes embedded (10[1])into its surface. (10[1])For 10 points, name this organelle that surrounds the nucleus, divided into smooth and rough types. ■END■ (10[1])