Single or double circular strand?

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hunterpostbacst

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Just want to check below.

Prokaryotes are bacteria?

Then, prokaryotes have a circular single stranded DNA?

In virus, bacteriophage has circular single stranded DNA? And, a plasmid in bacteriophage has circular double DNA?

These are what I clarfied before, but while reviewing bacteria in classification in kaplan BB, it says bacteria has a single double stranded circular loop of DNA.
 
Just want to check below.

Prokaryotes are bacteria?
Bacteria are prokaryotic cell types.

Then, prokaryotes have a circular single stranded DNA?
Yes!

In virus, bacteriophage has circular single stranded DNA? And, a plasmid in bacteriophage has circular double DNA?
Bacteriophages are virus that infect bacteria. I think viruses have linear DNA/RNA.
I don't think bacteriophages contain plasmids.

These are what I clarfied before, but while reviewing bacteria in classification in kaplan BB, it says bacteria has a single double stranded circular loop of DNA.
Hope this helps!
 
according to campbell/reece bacteria has double stranded, circular dna

Yeah... I have only heard of one instance of a single stranded dna genome (ttv? virus)... and I highly doubt there would be a question on the DAT regarding it...

Am I missing something here?
 
That's correct. Bacteria have dsDNA, which accounts for the characteristic expanding double-stranded replication "bubble" of DNA. Plasmids are double-stranded as well, hence how it's possible to use restriction enzymes that target palindromic sequences to cut sticky ends. Viral DNA come in all varieties: ssDNA, dsDNA, ssRNA, dsRNA. They can be linear or circular. I think herpes virus has circular DNA.

A bacteriophage is a virus that infects bacteria. No plasmids, unless you're referring to the genome itself, which could be double-stranded circular like a plasmid (there are many types of bacteriophages)