Viruses can be helical and icosahedral forms or even more complex structures. Most viruses are about one one-hundredth the size of the average bacterium.
Bacterium size is measured by a technique called Micrometry. With micrometry you can measured the size of very small beings like bacteria, cells, etc. This technique involves the use of a microscope in which the eye piece is calibrated in micrometers. A similarly calibrated slide is used for standardization. The specimen is then mounted and the size measured. Normally, the size of many cells are taken into account and an average value is taken, since all cells may not be of the same size.
1.1 to 1.5 µm wide http://www.mansfield.osu.edu/~sabedon/biol2010.htm
A bacterium that needs oxygen is called an aerobic bacterium
Bacterium
0.2 to 5 microns
50-500 nm
A virus is much much much smaller then a bacterium. Virus called phage can infect bacteria.
On average, a bacterium is 1 μm or 1 micrometer wide. Hope this helps!
Bacteria are all unicelular, but some live in colonies where they actually don't differ that much in cell size. 'Bacteria' is the plural form of 'bacterium'.
All bacterium is microscopic.
Viruses can be helical and icosahedral forms or even more complex structures. Most viruses are about one one-hundredth the size of the average bacterium.
Bacterium size is measured by a technique called Micrometry. With micrometry you can measured the size of very small beings like bacteria, cells, etc. This technique involves the use of a microscope in which the eye piece is calibrated in micrometers. A similarly calibrated slide is used for standardization. The specimen is then mounted and the size measured. Normally, the size of many cells are taken into account and an average value is taken, since all cells may not be of the same size.
100 times bigger
An organism of microscopic or submicroscopic size, especially a bacterium or protozoan.
A bacterium is general about 1 micron long. There are 1 million microns, or micrometers, in a meter, so the difference is about 1.5-2 million-fold.
1.1 to 1.5 µm wide http://www.mansfield.osu.edu/~sabedon/biol2010.htm