Deoxyribonucleic acid (DNA) is the carrier of genetic information, including for all known living organisms. The only known exceptions are RNA viruses.

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Does DNA react in all of the ways most other acids do?

As I understand it from my basic chemistry, there are some fundamental reactions that exist between any acid and other substances for example acid-base reactions that form a salt, and the existence of ...
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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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122 views

What are the costs associated with carrying lots of genetic material

What are the costs (if any) associated with carrying lots of genetic material (Big genome size)? energy for copying? raw material for copying? space in the cell? Maintenance cost (matter and ...
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Does our DNA change during our lives?

As far as I know, DNA is the construction protocol of all organisms on Earth. Does it change when influenced by time and environment (physical laws)? As parents with schizophrenia are more likely to ...
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597 views

What is it about the housekeeping genes that makes them almost immune to gene regulation?

When it comes to eukaryotes, including ourselves, we have all different kinds of specialized cells and tissues that are so different, yet originally all came from the same single cell. And apparently ...
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138 views

What is the effective relatedness of inbreeding?

If a human inbreeds with a relative, how distant does the relative have to be before the homozygosity in the child is no higher than if the mate were randomly chosen from the global population?
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855 views

BLAST DNA Sequences Reversed

I have been trying to learn some basic DNA sequencing techniques and have been using BLAST as a reference. I thought that I was starting to get it, but then I cam across this: It looks like it's ...
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239 views

Can forensic DNA analysis be used to generate a visual approximation of a suspect?

In light of the current US supreme court case, I'm curious if enough information can be teased out of a DNA sample to get a "reasonable" approximation of the suspect (never mind the legality). I ...
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254 views

Finding DNA from Amino Acid sequence problem

My attempt: First I took the single letter AA codes and made them amino acids. So, the first one is Trp which is 5'-UGG-3'. From this I got the DNA sequence 3'-CCA-5'. However, the correct ...
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977 views

Does extracted DNA degrade after a certain time period?

For direct use as template in PCR runs. Chelex 100 5-10% w/v extraction. Without listing the whole protocol, in the end the supernate is decanted off and then stored at 4°C. I was under the impression ...
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721 views

How is instinctual information encoded?

If instincts are passed on through genetics, how is that information encoded in DNA? For example, spiders instinctively know how to spin webs. Does that imply that the algorithm for web spinning is ...
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291 views

What kind of event would cause the current Mitochondrial Eve to be replaced by a new one?

Apparently all living humans are matrilineal descendants of a single woman who lived 200.000 years ago. She is called Mitochondrial Eve. But at the time she lived there was a different matrilineal ...
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881 views

Does every mitochondrion in a cell contain the same DNA?

I know that mitochondria of eukaryotes have their own DNA, more similar to that of bacteria than to the rest of the cell's DNA. I also know that a cell can have plenty of mitochondria, and I ...
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132 views

How realistic is to use DNA for long term storage?

This is mainly a followup question to the recent paper Next-Generation Digital Information Storage in DNA. Personally, while I agree about the data density of the format, I can't help point out the ...
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901 views

Why does A pair with T and G with C?

DNA is made up of pairs on AT and GC base pairs. I know that A only pairs with T and G only with C. Does this apply just to humans, or are there animals where T will pair with G? Also, surely there ...
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576 views

Looking for a DNA sequence

I am not a biologist. Please pardon me, if my question does not make sense. I am trying to obtain a DNA sequence for pattern analysis in Matlab. I used to generate random sequence ...
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Altering the human genome

I recently had a conversation with a rather unusual gentleman who was, let's say, more than a little partial to conspiracy theories. He has this idea that governments are lowering "nanowires" from ...
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124 views

Free Radicals for aging

From my understanding free radicals play a slight role in ageing. In what ways are they so damaging, and can a restricted diet reduce production of free radicals?
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65 views

Do DNA repressors exist?

I know about enhancers and the mechanism that lead them to increase the gene expression of their targets but I was wondering if similarly DNA repressors exist. I know about protein repressors but I am ...
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248 views

What causes skewed lanes in a DNA gel electrophoresis experiment?

In gel electrophoresis, what causes effects like these (see collumn 11 in the first one, an collumn 6 in the second). ? (These images were samples that I took from an online activity we did for ...
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591 views

What distinguishes “coding” and “noncoding” DNA from each other?

I've been reading a bit about "junk DNA" and how much of our genome consists of this "non coding DNA" in comparison to "coding DNA". I'm just an interested layperson but I thought all combinations of ...
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Why are 3 nucleotides used as codons for amino-acid mapping in DNA?

DNA is made of 4 unique nucleotides. When coding for a protein, a sequence of 3 nucleotides is used to code for each amino acid. Why are codons 3 nucleotides in length? A related question can be ...
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78 views

How does one measure the length of telomeres?

My questions are: What techniques are available for doing so? Are they destructive ? What is their accuracy ?
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288 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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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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91 views

How do nuclear receptors locate each other to form a DNA loop?

Nuclear receptors can influence transcription far up- or downstream from their own binding sites by looping DNA (Rubina et al.; J Mol Bio 2004). I am not sure how exactly the receptors first attach ...
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Difference in length of Okazaki fragments

The length of Okazaki fragments in the lagging strand is about 100-200 nucleotides in eukaryotes and about 1000-2000 nucleotides in prokaryotes. What (molecular mechanism, enzyme type ) ...
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60 views

Double stranded nucleic acids are more 'durable' than single stranded nucleic acids?

I'm struggling with a question I've been asked. "Why is double stranded genetic material more 'durable' than single stranded one?" I know that double stranded genetic material is more stable due to ...
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is it possible to completely reconstruct a family tree by DNA comparison alone?

Having DNA samples of all or almost all members of a population of, say, a few hundred or thousand individuals, is it possible to draw the entire family tree of those individuals? (Let's not assume ...
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432 views

What makes DNA sticky-ends sticky?

When restriction enzymes jaggedly cut double stranded DNA it results in so called sticky ends. What is the substance that makes the DNA sticky?
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441 views

How many transcription factors are there?

In molecular biology and genetics, a transcription factor is a protein that binds to specific DNA sequences, thereby controlling the flow (or transcription) of genetic information from DNA to ...
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188 views

What is the difference between sequence, reads, and contigs of genetic material?

Can someone explain the differences between sequence, reads, and contigs of genetic material such as DNA, if possible with an example? I am new to bioinformatics, and I have not found any conclusive ...
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112 views

How much DNA of mitochondrial origin is incorporated in main cell's DNA?

And especially three points : in which chromosomes is it located (especially for the human case) ? how do we know about it ? does the proportion and composition vary a lot from one eukaryot to ...
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405 views

What's the use of DNA sequencing results?

Suppose I sequence DNA of some organism (a human perhaphs) and now I have the entire DNA "string" - the sequence of nucleotides. What's the use of that? It's just a "string" where nucleotides encode ...
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121 views

Why does DNA have its name?

Why is DNA called deoxyribonucleic acid and not something else? I get the nucleic acid part (because that's what DNA is made of) but what about the deoxyribo- part, especially the ribo- part. Maybe ...
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Are there any DNA base sequences that are fully conserved between the genomes of all humans?

That is, they don't differ throughout the entire population. I understand of course that we can't DNA sequence every human, so by "fully" I mean there's an incredibly small probability of there being ...
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764 views

Possible reasons for DNA getting stuck in well

I am in the process of Library preparation for Illumina MI-Seq using mtDNA. Using NEB Hotstart LongAmp Polymerase, I was able to obtain upto 10kb amplicons of mtDNA. However, when I switched to a ...
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DNA extraction from agarose gel

Because DNA is soluble in water, is it possible to extract PCR product by dissolving excised gel containing the DNA band of desired length in water, mashing the gel piece with a pestle, centrifuging ...
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685 views

Does RNA polymerase move around DNA or does DNA rotate benath the polymerase?

I'm thinking of the human genome specfically, but more general answers are welcome. As RNA polymerase moves along the DNA helix it follows a single strand. The two DNA strands are unwound locally ...
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Why do DNA and RNA have the functions they have?

I know that there are two most important directions of genetic information transfer in living organisms: DNA->DNA and DNA->RNA. The first is replication, and the second is transcription. I wonder if ...
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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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310 views

why is DNA antiparallel? Can it be parallel?

My biology textbook mentions that DNA is antiparallel and it got me wondering... Can DNA be parallel? What would happen if it was parallel? could DNA still replicate right?
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Why differentiated cells can't “undifferentiate” (under normal conditions)?

In a process called differentiation, the cells of the developing organism undergo huge changes, which result in cells, functioning "completely" differently. Two cells are considered to be of different ...
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SNPs and locations

I am new to reading raw DNA. When comparing two people's raw data, why does one person have a different SNP than the other, at the same location, on specific chromosome? But on a different chromosome ...
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What regulates the timing of the motion of molecular machines during DNA Replication?

This question is about this video I found on Youtube. I just want to know what is the mechanism which regulates the timing of motion of the parts of these molecular machines. I know that those big ...
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190 views

How do scientists create specific mutations?

Suppose I want to create a mutant like Antennapaedia how will I go about accomplishing it ? I know that radiation and certain chemicals are mutagenic. So do scientists subject animals to such ...
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445 views

How can I predict DNA binding affinities from a protein sequence?

Are there any computational tools to predict the binding affinity to specific DNA motifs from protein domain sequence information?
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Basic Amino Acid Residue Binding Mechanism to DNA

I understand that many protein DNA binding domains bind to DNA via basic residues such as Arginine and Lysine. But what is the mechanism used to bind to DNA and where on the DNA would these residues ...
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50 views

Why aren't genetic triplets roughly evenly found in DNA?

Sorry, the page I linked to is huge and you'll need to do a text search for "CG" to find the part I'm talking about. I found a graph on this page (http://www.oftenpaper.net/sierpinski.htm) showing ...
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What is a good Non Fluorescent DNA Dye?

Can anyone suggest a dye which specifically targets DNA, but is not fluorescent? (We plan to mark DNA before observing it with RAMAN-Spectroscopy. Because of the weak Signal even a low emission would ...