Plasmid DNA is naked double stranded DNA that forms a circle with no
free ends. It is associated with few protein but contains RNA polymerase
enzyme. They are smaller than the host chromosome and can be easily
separated.
Chromosomal DNA is double stranded linear DNA molecular
associated with large proteins. This DNA exists in relaxed and
supercoiled and provides a template for replication and transcription.
It has free ends represented as 3′−5′3′−5′.