Land Area: 1  Land: 3,537,436 sq. miles (9,161,923 sq km) 2  Water: 181,274 sq. miles (469,497 sq km) 3  Total: 3,718,710 sq. miles (9,631,420 sq km)  Land Area: (individual 1  states) Land Area: (all countries)  Horizontal Width: 2,680 1  miles. Vertical Length: 1,582  miles.
Quick Answer. The smooth endoplasmic reticulum is the organelle responsible for the production of lipids in the cell. This particular reticulum also synthesizes carbohydrates and steroid hormones. The endoplasmic reticulum is made up of membranous sacs and tubules.
Energy Production and Storage. The primary role of lipids in your body is to provide energy for muscles and body processes. Fat is energy dense, containing 9 calories per gram, whereas protein and carbohydrate contain only 4 calories per gram. About half of the fuel your body needs when at rest or during everyday activity comes from lipids.