Kingdom MoneraMonera are the only kingdom composed of prokaryotic organisms

The major group of this kingdom is the bacteria that have a cell wall, and lack both membrane- bound organelles and multi-cellular forms

Bacteria may be solitary cells, filamentous, or colonial, Aerobic or anaerobic, Autotrophic or heterotrophic

Other groups of Monera include the cyanobacteria (autotrophic) and eubacteria (heterotrophic)

The Archaebacteria, the most ancient of this kingdom, are so different that they may belong to a separate kingdom

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1. Size• Bacterial cells are very small, • about 1-2µm in diameter and 10 µm long – One micrometer = 1/1000 mm.• Imagine looking at a dime from its thinnest side

and trying to slice it into a thousand pieces; that is the same as 1 µm.

Shapes of Prokaryotes

• Cocci = spherical (round)

• Bacillus = (rod shaped)

• Spirilla = helical (spiral)

Shapes3 basic shapes Cocci - sphere

Bacilli - rodsSpirilla – spirals

2 basic groupingsStaph - in clusters

Strep - in chains

Spiral

Rod shaped

Spherical

Streptococcus sp. Chains of nearly-spherical bacteria.From The Rockefeller University.

This spiral shaped bacteria is the causitive agent of syphilis Treponema pallidum

Bacterium Shapes

• Cocci~ Sphere shaped bacteria

• Bacillus~ Rod shaped bacteria• Spirrillium ~ Spiral shaped

bacteria• Flagella~ Leg-like structures

that help to propel the bacterium.

2. Lack membrane-bound organelles inside the cell

3. have few internal structures that are distinguishable under a microscope.

4. genetic information is in a circular loop called a plasmid

• E. coli cell dividing.

• E. Coli Grows in human intestine; – Has a single, circular

chromosome– contains DNA as

plasmids • Plasmids are extra-

chromosomal DNA

5. Strong cell walls: resistant to environmental changes