The cell without membrane bound organelles is called a prokaryotic cell. The prokaryotic cell have the simplest organization. The prokaryotic cell is simple, small and most primitive. They are probable the first to come into existence perhaps 3.5 billion years ago. The prokaryotic cell is the most primitive cells from morphological point of view. The prokaryotic cells are known for their rapid multiplications as compared to most of the eukaryotic cells. They vary in size.
Example- Bacteria, Blue green algae, Mycoplasma or Pleuro Pneumonia like Organisms (PPLO) .The prokaryotic cell do not show any intracellular compartments. A prokaryotic cell is essentially a one envelope system organized in depth.
1.Lack of organized nucleus. The genetic material is present in the form of nucleoid.
2.Nuclear membrane is absent
3. DNA not complex with histones
4.DNA in a circular form and not packed into chromosomes
5.Membrane bound organelles are absent
6.Cellular respiration is carried out by cell membrane
7.Absence of nucleoli and mitotic apparatus
8.Cell wall is made up of murein
9.The cell membrane may infold to form mesosomes.
10.Flagella are simple and made up of flagellin and 9+2 organization is absent
11. Cytoplasm does not show streaming movement
12.Microtubules are absent
13. Ribosomes are of the 70S type
14.Different kinds of pili are present
15.Replication of DNA occurs continuously throughout the cell cycle.