Concept 2 Review
Features of the Prokaryotic Cell
Prokaryotic cells have the following features:
- The genetic material (DNA) is localized to a region called the nucleoid which has no surrounding membrane.
- The cell contains large numbers of ribosomes that are used for protein synthesis.
- At the periphery of the cell is the plasma membrane. In some prokaryotes the plasma membrane folds in to form structures called mesosomes, the function of which is not clearly understood.
- Outside the plasma membrane of most prokaryotes is a fairly rigid wall which gives the organism its shape. The walls of bacteria consist of peptidoglycans. Sometimes there is also an outer capsule. Note that the cell wall of prokaryotes differs chemically from the eukaryotic cell wall of plant cells and of protists.
- Some bacteria have flagella which are used for locomotion and/or pili, which may be used to pull two cells in close contact, and perhaps to facilitate the transfer of genetic material.