Plasmids are pieces of DNA, that bacteria incorporate into their own genome:

 

In the process of Conjugation, bacteria transfer genetic material to each other, through extra-chromosomal pieces of DNA, called Plasmids. Bacteria are normally haploid, but bacteria that receive Plasmids become diploid for any genes contained on the Plasmids (Teaching Company Biology, lect. 27).

Such seems superficially similar, to (lysogenic) bacteriophage virus DNA, which enters bacterial cells, and is incorporated into the cell's internal functionings. Perhaps Plasmids underlie the Eukaryotic transition to diploid-ism, representing some sort of "proto-sexual reproduction" ??

Plasmids are pieces of DNA, that bacteria incorporate into their own genome:

 

 

Such seems superficially similar, to (lysogenic) bacteriophage virus DNA, which enters bacterial cells, and is incorporated into the cell's internal functionings. Perhaps Plasmids underlie the Eukaryotic transition to diploid-ism, representing some sort of "proto-sexual reproduction" ??

 

Plasmids are basically rings of usually uncoated DNA, which bacterium can then incorporate into their system to cause a change which is usually made to be non-lethal, but rather allow to bacterium to make some type of enzyme that lets it glow or glues sand pebbles together. Viruses are just clumps of DNA surrounded by a coating of protein, which just enter a cell by chance and have as much of its DNA copied as the cell can hold.

Edited January 22, 201115 yr by steevey

Plasmids are just circular DNA wich can enter cells via different mechanisms like competence factors and etc, but the difference with viruses is that a virus can enter a cell or inject its DNA using specific membrane proteins, then the Viral DNA can be integrated into the cell genome, maybe you're confusing that some viruses can inject their DNA and it can stay as a plasmid inside the cell without integrating into the cell genome for some time, then it gets replicated and divided into new cells, and then after some time this Viral DNA can integrate the cells genome and start the infection, this depends on the cell culture conditions and the cell itself.

 

Plasmids can also be integrated into the genome but its more likely that they will remain in their circular form and continue to be replicated with as the cells divides itself, this will continue until the cells doesnt require the genes encoded into the plasmid anymore.

 

greets