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plasmid DNA and chromosomal DNA in bacterial cells

are plasmid DNA and chromosomal DNA the chromosomes in a circular shape?
Hi im alevels too. From what I understand, DNA in prokaryotes doesnt close around histones in prokaryotes. I won't call it chromosome but maybe just circular DNA ?
Reply 2
Original post by BrightBlueStar11
are plasmid DNA and chromosomal DNA the chromosomes in a circular shape?

Can you rephrase your question, it doesn’t make much sense.
Original post by BrightBlueStar11
are plasmid DNA and chromosomal DNA the chromosomes in a circular shape

Both are in prokaryotic cells and are found free floating in the cytoplasm however, chromosomal DNA carries genes needed for everyday functions but plasmids have extra genes e.g. antibiotic resistance which increase their chance of natural selection. Plasmids can also be transfered between prokaryotes in horizontal gene transfer and chromosomal can't. However during binary fission each daughter cell has the same number of chromosomal dna but a variable number of plasmids is variable
Hope this helps, let me know if you have any more questions
can you call both "plasmid DNA" and "chromosomal DNA" as "chromosomes"?

Original post by Jpw1097
Can you rephrase your question, it doesn’t make much sense.
Original post by BrightBlueStar11
can you call both "plasmid DNA" and "chromosomal DNA" as "chromosomes"?

They both contain chromosomes but aren't chromosomes
Original post by Jess_Lomas
They both contain chromosomes but aren't chromosomes

oh I thought they were just chromosomes but in a circular shape instead of thread-like ones.

thanks tho!
Reply 7
Original post by BrightBlueStar11
oh I thought they were just chromosomes but in a circular shape instead of thread-like ones.

thanks tho!

Yes, bacteria have a single chromosome in addition to plasmids. Both the chromosome and plasmids are circular.
Original post by Jpw1097
Yes, bacteria have a single chromosome in addition to plasmids. Both the chromosome and plasmids are circular.

sorry just to clarify. So, both "plasmid DNA" and "chromosomal DNA" are chromosomes. Each bacteria possesses a single chromosome ("chromosomal DNA") or additional chromosomes ("plasmid DNA")?

just started my biology studies :colondollar:
Original post by BrightBlueStar11
sorry just to clarify. So, both "plasmid DNA" and "chromosomal DNA" are chromosomes. Each bacteria possesses a single chromosome ("chromosomal DNA") or additional chromosomes ("plasmid DNA")?

just started my biology studies :colondollar:


Are you taking edexcel? Then bacteria don't have chromosomes ; they have circular DNA.
Original post by thomas.rhett
Are you taking edexcel? Then bacteria don't have chromosomes ; they have circular DNA.

I don't do edexcel but for aqa they accept either on the mark scheme
Original post by thomas.rhett
Are you taking edexcel? Then bacteria don't have chromosomes ; they have circular DNA.

Bacteria are considered to have a single, circular chromosome.
Original post by BrightBlueStar11
sorry just to clarify. So, both "plasmid DNA" and "chromosomal DNA" are chromosomes. Each bacteria possesses a single chromosome ("chromosomal DNA") or additional chromosomes ("plasmid DNA")?

just started my biology studies :colondollar:

No, plasmids are not considered chromosomes. They contain fewer genes than the chromosome and are often passed between different bacteria.
Original post by Jpw1097
No, plasmids are not considered chromosomes. They contain fewer genes than the chromosome and are often passed between different bacteria.

thanks :smile:
can u also help me with this one plz?

when the translocation happens in plant phloem, does it transport food molecules (e.g. sucrose) in a form of cell sap (which is sucrose with water)?
do chromosomes (including chromosomal DNA found in bacteria) have proteins called histones?

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