DNA, or deoxyribonucleic acid, is the carrier of genetic information for the vast majority of living organisms. The only known exceptions are RNA viruses.
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115 views
What is the origin of “melting” in molecular genetics?
I'm reading some papers about prokaryotic transcription mechanisms, and I've come across a term I haven't heard before: DNA melting or promoter melting. After reading a bit, it's pretty clear that ...
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1answer
469 views
Are human chromosomes connected or separate molecules?
Do the 46 human chromosomes form a single unbroken DNA helix? Or is it rather that a human's genome consists of 46 disconnected helices?
If it is the former, does the common numbering scheme for ...
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3k views
Why do we add salt when precipitating DNA?
All the DNA extraction protocols I have seen involve adding salts to the extraction buffer. What is the purpose of the salts? What happens if they aren't included?
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Does an annealing temp higher than primer's Tm contribute to primer dimer?
I am attempting to reproduce results from a number of journal articles all referring to the same SNP. In doing this I'm using the same primer set outlined in the articles. When I attempted a run the ...
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504 views
How do cockroaches resist the effects of ionizing radiation?
Cockroaches are very hardy insects. It is known that, among other things, they are able to withstand bursts of ionizing radiation that would kill a human being.
The explanations of this observed ...
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269 views
Do mitochondria simply automatically convert glucose to ATP?
I wonder whether there is any intelligent decision-making in mitochondria in the timing of their operation.
Do they simply begin ATP production as soon as the correct reactants are present?
Or, ...
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137 views
What is the benefit for cells having the ATP production regulated in mitochondria compared to being from the nucleus?
Mitochondria have their own DNA and appear to be loosely connected to the nucleus and it role.
Why are the functions of mitochondria not in the nucleus? Why doesn't the nucleus control the ...
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3answers
435 views
What implications has the missing 2'-OH on the capability of DNA to form 3D structures?
The chemical difference between RNA and DNA is the missing 2'-hydroxyl group in the nucleotides that build DNA. The major effect of that change that I know of is the higher stability of DNA compared ...
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128 views
How can I produce milligram quantities of an isotope-labeled DNA oligomer?
I'd like to produce a specific DNA sequence on a milligram-scale and 13C15N-label it. The sequence is around 35 nucleotides long, so chemical synthesis is out due to the exorbitant costs.
I'm also ...
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1answer
179 views
Abiogenesis: Beyond the research journals as a lead in to discussions on evolution
I just came across this abstract:
Aminoacyl-tRNA synthetases (aaRSs) are responsible for creating the pool of correctly charged aminoacyl-tRNAs that are
necessary for the translation of genetic ...
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4answers
1k views
Life without DNA?
I'm by no means an expert in the field, merely a curious visitor, but I've been thinking about this and Google isn't of much help. Do we know of any lifeforms that don't have the conventional ...
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Why is DNA replication performed in the 5' to 3' direction?
DNA replication goes in the 5' to 3' direction because DNA polymerase acts on the 3'-OH of the existing strand for adding free nucleotides. Is there any biochemical reason why all organisms evolved to ...
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Could Junk DNA be used as a Turing Machine by nature?
In what ways has DNA been studied to see if there a "programmable" aspect to it?
Has nature produced anything resembling a Turing machine within the cell, perhaps using the "junk DNA" as its code? I ...
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667 views
What conditions should I use for Gel Red staining?
What are the optimal staining conditions when using Gel Red? So far, since we have started using it, the gels ran in our lab have been of very poor quality. The bands are very blurred and often ...
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1answer
120 views
How can you identify if a person is homozygous for a certain allele?
I've been thinking about starting a small private research project. In this project I need to find out whether a person is homozygous for a certain allele. The reason for this is that I'm really ...
