
TEACHER: The multi-layered membrane systems of the cytoplasm are the smooth endoplasmic reticulum, the rough endoplasmic reticulum, and the Golgi body. Now, the smooth endoplasmic reticulum is concerned with the manufacture of lipid molecules.
Cytoplasm: all of the material within a cell, enclosed by the cell membrane, except for the cell nucleus.
Endoplasmic reticulum: the transportation system of the cell, and has many other important functions. It is made up of the rough endoplasmic reticulum and smooth endoplasmic reticulum.
Golgi body (or Golgi apparatus): a sub-unit of most cells, particularly important in processing proteins.
Lipid: a broad group of molecules which includes fats, fatty acids, cholesterol, and fat-soluble vitamins (such as A, D, E, and K).