The Cell is the fundamental unit of life.
Cells posses a genetic program and the means to use it.
The two fundamentally different classes of cells are the prokaryotic cells and the eukaryotic cells. Eukaryotic cells have complex chromosomes composed of DNA and associated proteins that are capable of compacting into mitotic structures. Eukaryotic cells contain membranous cytoplasmic organelles. Eukaryotic cells have a complex cytoskeletal system. Eukaryotic cells are capable of phagocytosis and endocytosis.