<u>Characteristics of bacteria:</u>
size: The size of bacteria varies from their shapes like spherical bacteria has a diameter of 0.5-2.0 micron, rod-shaped bacterias length of 1-10 micron
structure: Bacteria are prokaryotic, unicellular microorganism. There are no membrane-bound organelles and true nucleus, they have the cell wall, DNA is in the form of nucleoid or linear plasmid.
shape: The most common three shapes of bacteria are coccus (spherical), bacillus (rod-shaped), and spiral. Exception is polymorphic bacteria which can have different shapes. They can be filamentous, star-shaped, rectangular also.
reproductive cycle: Bacteria reproduce asexually by a process called as binary fission, budding and sporulation. The binary fission results in the formation of two genetically identical cells. Their growth is exponential. They can exchange genetic information with each other by the process of conjugation, transduction, or transformation.
<u>Characteristics of virus:</u>
size: virus range from 20 to 400 nanometres in diameter much smaller than bacteria.
structure: A typical virus consists of single or double-stranded RNA or DNA, protein coat k/a capsid and a lipid envelope
shape: It can be hellical, polyhedral, icisahedron depending on the capsid pattern
reproductive cycle: Virus replicate or reproduce inside the host body by the process of lytic infection. In lytic cycle virus attaches itself to the host cell and injects the host cell with its nucleic acid. They use the replication machinery of the host cell to replicate their DNA and eventually new protein or virus.
