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.
Lipids play important roles in the normal function of the body: 1  To serve as structural building materials for cell membranes and organelles. 2  To provide energy for the organisms, which is greater than whatâs provided by carbohydrates or proteins. 3  To serve as signaling molecules and molecular messengers in the body.