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What is a nucleoside, where is it found or how is it synthesised? (Genetics)

What is a nucleoside, where is it found or how is it synthesised?
Original post by Roman hang Limbu
What is a nucleoside, where is it found or how is it synthesised?


A nuceloside is a nucelobase bound to a sugar. So a nudelotide such as ATP or GTP is a nuceloside tri-phosphate.

For their synthesis, I'd direct you to this link. Quote me if you have further questions.
Original post by Kvothe the Arcane
A nuceloside is a nucelobase bound to a sugar. So a nudelotide such as ATP or GTP is a nuceloside tri-phosphate.

For their synthesis, I'd direct you to this link. Quote me if you have further questions.


During DNA sequencing when the DNA is extracted, is it from just one cell or multiple cells?
Also why is the VNTRs so unique for each individual?
Thankyou for replying.
Original post by Roman hang Limbu
During DNA sequencing when the DNA is extracted, is it from just one cell or multiple cells?
Also why is the VNTRs so unique for each individual?
Thankyou for replying.


My memory is slightly fuzzy, it has been quite some time since I touched upon this :P.

(i) During the process of isolating DNA, DNA is extracted from a sample of cells of interest to produce long samples of DNA required for the sequencing process. So long strands of DNA pretty much equals to a successful DNA extraction.

(ii) VNTRs are essentially made up of genetic information inherited from a person's parents, and usually comes as a combination of the two parents' VNTRs respectively. A person cannot have a VNTR that his/her parents did not possess. So in layman terms, the possible combinations for VNTRs are as numerous as the stars in the sky. Try to find two people with the same fingerprint and you'll see what I mean.
Original post by mrjudge
My memory is slightly fuzzy, it has been quite some time since I touched upon this :P.

(i) During the process of isolating DNA, DNA is extracted from a sample of cells of interest to produce long samples of DNA required for the sequencing process. So long strands of DNA pretty much equals to a successful DNA extraction.

(ii) VNTRs are essentially made up of genetic information inherited from a person's parents, and usually comes as a combination of the two parents' VNTRs respectively. A person cannot have a VNTR that his/her parents did not possess. So in layman terms, the possible combinations for VNTRs are as numerous as the stars in the sky. Try to find two people with the same fingerprint and you'll see what I mean.


Thank you for replying much appreciated, and you have cleared a few confusion also.
Original post by Roman hang Limbu
Thank you for replying much appreciated, and you have cleared a few confusion also.


No problem :smile:
Original post by mrjudge
No problem :smile:


Hello, sorry for bothering you but i have one more question....Is double stranded DNA or single stranded used for Electrophoresis during DNA profiling? I checked my school book and they used "alkali solution to break the double strand" and this youtube video i watched didn't mention anything about breaking the double strand.... I am not sure which one it is...
Original post by Roman hang Limbu
Hello, sorry for bothering you but i have one more question....Is double stranded DNA or single stranded used for Electrophoresis during DNA profiling? I checked my school book and they used "alkali solution to break the double strand" and this youtube video i watched didn't mention anything about breaking the double strand.... I am not sure which one it is...


No worries.

So do you need to break the double-strand in order to carry out electrophoresis? The answer is no, not always. Generally, electrophoresis can be conducted on both DNA and ssDNA. This includes DNA profiling. For example, in the common procedure for creating a DNA fingerprint, DNA is not broken before electrophoresis, in fact it is broken by blotting after the process in order to undergo further testing by autoradiography.

Now, I do not know how exactly the sentence "alkali solution to break the double strand" was worded in your schoolbook. However, it is likely that the author merely decided on a sample of ssDNA for analysis.
(edited 7 years ago)
Original post by mrjudge
No worries.

So do you need to break the double-strand in order to carry out electrophoresis? The answer is no, not always. Generally, electrophoresis can be conducted on both DNA and ssDNA. This includes DNA profiling. For example, in the common procedure for creating a DNA fingerprint, DNA is not broken before electrophoresis, in fact it is broken by blotting after the process in order to undergo further testing by autoradiography.

Now, I do not know how exactly the sentence "alkali solution to break the double strand" was worded in your schoolbook. However, it is likely that the author merely decided on a sample of ssDNA for analysis.


Oh alright thanks again lol. Can you help me with this one last question please?
My book doesn't specify this but how do scientists exactly extract just the VNTRs/STR DNA to carry out DNA profiling without knowing what base sequences there already was then if you already knew this then DNA profiling wouldn't make sense. Does the enzyme restriction endonuclease "cut" VNTRs and how will scientists extract just VNTRs/STRs from the whole mixture of fragments of DNA.

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