What do Plasmids in Animal Cells Do? :confused:

Any Help is appreciated. Thanks!!!

Plasmid are usually found in only organelles like mitochondria and chloroplasts. This is because billions of years ago these organelles we once bacteria that were engulfed by an animal cell and developed a symbiotic relationship with the animal cell. Most animals cells can not replicate plasmid from one generation to another and the plasmid must be incorporated into a chromosome… Though I think some plants can carry and replicate plasmids in their nuclei.

& a plasmid has to be inserted, via a vector of some sort, inside of its host (like bacteria.) which will then replicate independently of host's genetic makeup.

A plasmid is a ring of DNA containing a few genes...bacteria trade plasmids with eachother like trading cards :D

yay!! *is quite surprised* a man of science that has managed to retain his sense of humor!:D btw...what types of cards might the little buggers be trading..?

Antibiotic resistant Babe Ruths for one!

a plasmid IS a vector

actually, the mitochondrial and chloroplast genomes are NOT considered plasmids.

and why is that? :confused:

because plasmids are small circular bits of DNA that are transferable between bacterial cells. that is how they are vectors, or used as vectors in cloning. mitochondrial and chlorplast genomes don't have these characteristics.

There is no physical difference between a plasmid and the main chromosome of bacteria, plasmids though can replicate on their own and some are dispensable but that’s all. Many plasmids are essential to a bacteria’s survival and can be considers part of the bacteria’s genome as another chromosome. Some plasmids can insert them selves into another plasmid or main chromosome (episomes).

a plasmid IS a vector


well, yes and no...i mean, it can be considered one given the circumstances involved...take a further look into the definitions of plasmids and vectors. thanks. :)

So, What is the Function of these Plasmids? I mean what do they do inside the bacteria? and also how do the bactria trade plasmids and why? I still am Confused...:o

plasmids stored genes. Unlike in higher life forms like us a plasmid chromosome is a circular piece of DNA that is super coiled and has no protein superstructure. The main way plasmids are traded is by F pili: A bacteria will come up to another bacteria, a connection will be made (a pilus), the plasmid will reproduce and the replicated plasmid (single stranded dna) strand will be pumped into the recipient bacteria, once in it new host the replicated plasmid will become double stranded and connects it ends together to form a circular piece of dna… some plasmids will incorporate them selves into the host chromosome then (a episome). The normal circular dna of bacteria as has no name and can be referred as a plasmid at times.

the reason I am calling all plasmids vectors; vectors carry things from one place to another. because one of the characteristics of plasmids is the ability to leave one individual organism or cell and enter another, makes them vectors. in this sense all plasmids are vectors, however, not all vectors are plasmids. You said, "a plasmid has to be inserted, via a vector of some sort," which is wrong as plasmids are the vectors themselves and are able to enter another cell(or bacteria) without help from any other vector.

the reason plastid genomes (and prokaryotic genomes; from which plastid genomes are presumably derived) are NOT plasmids is because they lack this characteristic (or ability) of moving between individuals or individual cells. Although prokaryotes can exchange genomic DNA through conjugation, this is very different than plasmid transfer. Plasmids and plastid genomes do share some characterisitics, i.e. circular dsDNA, but plastid genomes (and prokaryotic genomes) are much much larger than plasmids.

WellCookedFetus; I admire your willingness to look-up and research points of discussion. Your desription of plasmid transference between bacteria was limited to F-factors. This is not how all plasmids are transferred. For example, competent bacteria (those bacteria with pili) can take-up any plasmids in the environment without the need of other bacteria or direct transfer. In fact, that's how it's done in a cloning lab; the plasmid vectors, already circular and double-stranded and containing the insert gene of interest, are mixed with the competent bacteria and shocked with heat or electricity and the plasmids are taken-up by the bacteria.

It's thought that the production of pili by bacteria is a response to some environmental stress. These pili facilitate the exchange of plasmids and would be selected for if the individuals have a better chance of surviving environmental stress with plasmid exchange than without.

Yes that true but most plasmids are nature transmitted through pilii and so I felt that was the only one to discuss.

Also pulling out a genetics book that I can't trade in is not much of researching a topic... don't start disrespecting people or you might find everyone correcting every minor error you make and claiming your stupid for not mentioning something because truthfully you did not have the time.

hei fetus,

i don't think paulsamuel was being sarcastic here. He was probably sincere when he said that he admired your willingness to look-up and research points of discussion.

He just pointed out a detail that happens to be a very important detail. And personally I agree with him this time.


edit: thought I might have been unclear and added a bit

And I thought I mention that detail?

Originally posted by WellCookedFetus
And I thought I mention that detail?

yeah, but you also know that I am a very lazy reader and obviously I missed that...stupid me...again

yes, you are correct...but, you know me...everthing in a nutshell;D a plasmid is a plasmid is a plasmid, HOWEVER a plamid CAN BECOME a vector when being used by researchers to introduce/trasfer material into bacterial cells. in otherwords a plasmid, by means of the very action its causing "becomes" or "turns into" a vector; vector, meaning "carrier". btw...yeah, as improbable as it seems, although rare, plasmids can also be found in eukaryotic cells...not only in the DNA of bacterium.

Are plasmids replicated by the human body, or is there still some form of a symbiotic relationship after all these years?

BTW, I watched a great Japanese movie the other night in which mitochondia waited billions of years, then took over humans to form a superior organism.

Was that Akira?

Mitochondria and chloroplast reproduce on there own.

:D :D ya know...i am in such a good mood tonight...i've decided to play hookey...and, furthermore...i don't give a flying fig about plasmids !!:D

If plasmids are not a part of human dna, then at what time are they introduced ?

Originally posted by proteome
If plasmids are not a part of human dna, then at what time are they introduced ?

when the eukaryotic and prokaryotic cell decided to go for some serious symbiosis and live together under one roof???

Originally posted by spuriousmonkey
when the eukaryotic and prokaryotic cell decided to go for some serious symbiosis and live together under one roof???

I had asked if plasmids were a part of the human genome, and the answer that I received, was no. I believe that means that when the genes from egg and sperm do not contain plasmids, therefore the human body must be introduced after conception.

What I am asking is...at one time do plasmids get introduced to the human cells?

do plasmids get introduced to the human cells?


yes...by way of a VECTOR, or another way of putting it is: in the action of the plasmid entering[ie. insertion] a cell, the ACTION itself is causing the plamid to become a/the vector. do you now see the difference between the words "plamsid" and "vector"? and, btw...like i said some eukaryotes do have plamids within their Dna.

humans don't have plasmids. The only eukaryote that i have heard that contain plasmids is a plant species, but yeast and maybe some fungi probably could be found to be plasmid containing

yep....and, like i said..."some" eukaryotes..... i did not say humans....


but, it might actually be discussable....

That movie akira was awesome. I had a hard time understanding what was going on as I was half asleep.