Before Cells

Cells are the basic building blocks of all living creatures. However, they didn't always exist as cells. Each cell is formed from a varieties of molecules that can be classified into several major families such as Nucleic Acids and Amino Acids. Through cycles of selection from environmental pressures, these molecules come together to form the first primitive cell, for the sole purpose of ultimate survival.

In this section, you will meet many of the molecules that compose the cell. You may select from the following families of molecules:

	Nucleic Acids Click here to learn about the molecules responsible for storing the blueprint of life, DNA and RNA.
	Amino Acids All cells are constructed by the coagulation and interaction of proteins. Click here to learn about subunits that form proteins.
	Sugars Sugars is the preferred source of energy for cells. Click here to learn about the chemical properties of sugar molecules.
	Lipids The cell membrane is composed mostly of lipids. They are also used for energy storage in animal cells.
	Water There would not have been life on earth without water. Click here to learn about why water molecules are so crucial to life.