Characteristic features of five kingdom system

Monera: Also known as Prokaryotae

• Prokaryotic: This phylum includes all organisms made up of prokaryotic cells, i.e., the cell in which well defined nucleus and membrane bound organelles are absent.
• Unicellular: These simple organisms are always unicellular, i.e., a single cell performs all life sustaining functions and able to live as an independent organism.
• Mode of nutrition: These organisms can be autotrophic or heterotrophic, i.e., either they can synthesize their own food or obtain their food from other organisms.

Example:

Autotrophic: Cyanobacteria or blue-green algae

Heterotrophic: Most bacteria, Mycoplasma

• Cell wall: They may or may not have cell wall.

Cell wall present: Bacteria, Cyanobacteria

Cell wall absent:  Mycoplasma

• Size:  size is in the range of 0.15 micron to 2 microns.
• Reproduction: these organisms reproduce by asexual mode usually by binary fission or budding.

Sub-Classification of Phylum Monera

• Monera was further classified into two sub-kingdoms by Carl Woese in 1977.

Archaebacteria:

• Most archaebacteria are autotrophic. The source of energy used for synthesis can be chemical like methane, ammonia, hydrogen sulphide etc or light energy.

Eubacteria:

• Bacteria have an outer cell wall the plasma membrane & cytoplasm with ribosomes.
• A circular strand of DNA, usually coiled into one region of the cell, the nucleoid, serves as the single chromosome. They differ in their shape:

1. Bacilli: Rod-like

2. Coccus: Spherical

3. Spirilla: Spiral etc.

Bacilli- E. Coli:

Cocci- Staphylococcus aureus:

Spirilli- Clostridium: