Cell

Wednesday, January 28, 2009

A cell is a small, usually microscopic, mass of protoplasm which is bounded externally by a semipermeable membrane, including one or more nuclei and various non-living products, capable of performing the fundamental functions of life, forming the least structural unit of living matter.

The are two type of cells: a Eukaryote, and a Prokaryote cell. Prokaryotes differ from eukaryotes since they lack a nuclear envelope and a cell nucleus. Prokaryotes also lack most of the intracellular organelles and structures that are seen in eukaryotic cells.

A cell consists of a plasma membrane, which surrounds the body of the cell, a cytoplasm, and at the center a nucleus, which is surrounded by the nuclear membrane. The cytoplasm contains the Golgi apparatus, mitochondria, endoplasmatic reticuli, vesicules, etc. The chromosomes are contained in the nucleus of the cell.