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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Why Only DNA can Contain Hereditary Material?

Well I'm well aware that it is proven that DNA contains genetic material via transformation and Hershey-Chase Experiment of T2 bacteriophage. Still I was wondering what is the reason only DNA ...
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What triggers DNA to produce proteins?

What is the trigger for DNA to produce proteins or RNA? I have found enough material to study the inner workings of the cell and DNA; but, I can't find an explanation of the mechanics the cell uses ...
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RNA polymerase question

In this question we are examining a bacterial RNA polymerase that elongates at 20 codons per second. Question 1: How long will this RNA polymerase take to transcribe the Lac Z gene at 3510 base pairs? ...
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Difference between mice and rats

What is the actual biological difference between mice and rats? Are they actually the same thing with two different names depending on appearance (are they all mice for instance and we call the larger ...
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What are the major causes of mutations in DNA?

I know that point mutations can change the base sequence of a gene by altering a specific codon that codes for a particular amino acid. Are these mutations purely random events that occur when DNA is ...
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Turning publicly available genome data into proteins

I'm a computer scientist who is starting to dabble with biology. My eventual goal is to model different kinds of cells with a computer program. As of right now, I'm just trying to take some smaller ...
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High sequence similarity but start codon isn't methionine

I have noticed in a particular genome sequence of a prokaryote that various regions in a sequence share similarity which is high(>80%) with known proteins. However, the start is not a methionine. Is ...
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More entropy: Atom or Macromolecule? [closed]

A question that appeared on my last exam was : Which of the following has greater entropy A) An atom B) A macromolecule The question doesn't specify anything else(i.e. type/size of atom or ...
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Is there variation of AT/CG ratio along species?

Chargaff's rules say that the number of Adenine of the number of Thymine in a genome are equal (nA=nT) and similarly nC=nG. This makes obvious sense knowing that C binds to G and A to T. But what ...
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Separating DNA Fragments by Gel Electrophoresis. Are all the strands for one size the same?

My apologies if my question is too basic, and please point me to a more appropriate forum. I am reading the textbook "Essential Cell Biology" by Alberts et al, and am consulting other sources as ...
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What risk to DNA does long-term exposure to low-dose radiation pose?

A new study from MIT scientists suggests that long-term exposure to low-radiation poses no risk of DNA damage for mice (it is also important to note that mice are unusually susceptible to cancer). So ...
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Clarification on the “orientation” of chromosomal rearrangements

I need some clarifications on the concept of "orientation" in case of chromosomal rearrangements. Given a deletion event on a chromosome for example, is the resulting DNA at the breakpoint always in ...
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How to measure quality and quantity of DNA?

I would like to mesure DNA. I quantify the concentration with Qubit fluorometer, but I would like to know also quality of DNA. I try BioAnalyzer (Agilent),but without success. Bioanalyzer measure DNA ...
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How to learn molecular biology through pubmed research articles?

Instead of using a textbook, is there an alternative curriculum, that simply lists a set of pubmed research articles for each topic covered in a typical undergrad molecular biology course? I am ...
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Pros/cons: linear vs. circular DNA [duplicate]

Why did Eukaryotes evolve to have linear DNA and not circular like Prokaryotes? What are the pros and/or cons?
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How much DNA of Albert Einstein is recoverable?

Since there seem to be five biological descendants of Albert Einstein, and the original chromosomes of him distributed among them ... Is it possible to recover enough DNA of an individual from his ...
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What is the most genetically simple organism except viruses?

What is the most genetically simple organism (except viruses) on this planet? By simple I mean the least number of genes.
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What is DNA binding domain? It is not clear what the domain means

I am confused about the term DNA binding domain. Does it mean that there are some parts of the DNA that tends to coil up? Does it happen because some proteins tend to stick around that area? Also it ...
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Self pairing in DNA

I know that ssRNA molecule can fold over itself (e.g. in t-RNA). Can DNA do the same? Is there any example of this in nature? Why is this phenomenon more common in RNA than in DNA?
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DNA replacement: new species

This is a hypothetical question What would happen if the DNA of a prokaryote was replaced with the one of a prokaryote of another species, would the cell structures change and adapt to the new DNA ...
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dsDNA translation

Since DNA is double stranded and each strand is complementary to the other, the codons on each strand will come out to be different after transcription(depending on the reading frame). Does this mean ...
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Question about Autosomal Recessive Alleles

I had a homework question that I could not figure out. It states: A woman has cystic fibrosis in her family and did not want to have a child that suffered from the disease. She and her spouse ...
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388 views

Can replication occur if DNA is methylated?

Can a methylated strand of DNA be replicated without removing methylation? Does it make any difference if the strand is methylated or not (during replication)?
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How does the DNA know which chain has error in repairing?

As we know, the DNA has more stability than RNA, if one chain has broken or accidentally distorted, it can be repaired by the other one. Suppose there is a segment AGTC, its peer is GACT. Now its ...
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Is episome a plasmid or a virus?

A plasmid is a small DNA molecule that is physically separate from, and can replicate independently of, chromosomal DNA within a cell. In general, in eukaryotes, episomes are closed circular DNA ...
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How are atoms in benzopyridines and benzopurines numbered?

I am well-aware of the numbering system used for the traditional bases, as seen below. My question is how are the atoms in the size-expanded bases seen in xDNA and xRNA numbered?
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what DNA you pass on to offsprings?

Our body contains many different types of cells and each of those cells have their own DNA (correct me if wrong) like skin cells their own DNA that makes them skin cells instead of muscle cells. So ...
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How to perform a DNA structural alignment in pymol

How can I "fit" two DNA structures having different nucleotide sequences in pymol? I would like to use the structure of a DNA binding protein in pdb (1h9t), which is bound to DNA in the pdb file, ...
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Walk me through microsatellite markers and PCR

Three polymorph microsatellite markers are used to try and narrow down the location of a disease locus, with the use of PCR with 2 flanks on each side of the actual polymorphic area. The PCR ...
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169 views

How fallible are DNA paternity tests?

Is it possible to get either a false positive or a false negative from a DNA paternity test and what would be the likely mechanisms behind this? For example, is it possible that a father's DNA could ...
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The move from RNA to DNA and the necessity of reverse transcriptase

In this piece about giant viruses and the origin of life, in the context of the move from RNA world to DNA world, virologist Valerian Dolja states: In order to move from RNA to DNA, you need an ...
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Is there a way to measure the amount of bytes that are possible to encode in a DNA molecule?

When I saw a DNA molecule for the first time, it kinda reminded me of a hard drive. It consists of slots and there are some possible combinations for each slot; in the hard drive these possible ...
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Are genes uniformly dispersed throughout the genome?

I think that telomeres and centromeres are regions with a very low gene content (= regions that contain few genes). To the exception of telomeres and centromeres, are genes uniformly distributed ...
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Why would mutation rates increase in a tumour?

This article describes a tumour: Swanton found that even the primary tumour was surprisingly varied. He found 128 mutations among the various samples, but only a third of these were common to all ...
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Gene frequency problem

1/330 of white people in south Africa have a disease called Porphyri. What is the frequency of the gene if it is inherited autosomal recessive? This one I understand. The genotype frequency is $q^2 ...
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Restriction sites

I would like to know: how many restriction sites does a restriction enzyme use on a DNA molecule? In other words: If a sequence on a plasmid contains the following bases: ATTGCAGTCTG and I want ...
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How would you affect bulk DNA gene therapy for a human?

Let's imagine that we understood DNA programming and our genome very well and realized that there were some significant flaws (we die, we need sleep, etc.) And let's imagine that we understand how to ...
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How can I re-format my DNA motifs' position weight matrices?

I am working with a set of DNA motifs that are predicted as potential regulatory motifs (e.g. transcription factor binding sites). The motifs belong to several species, and I wanted to cluster these ...
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Telomere shortening during replication

It is widely know that each cell cycle during DNA replication some fraction of the telomeres is lost, and this phenomenon is called the end replication problem. Well this is due to the fact that the ...
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What happens when cells in your body run out of telomeres?

In my biology book I read about an experiment where the genes encoding telomerase were 'knocked out', but they could still live a normal life and no adverse effects were noticed until the 6th ...
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How distantly related are eusocial insects? Aren't members of a species much more related than 1/4, 1/2, or 3/4? [duplicate]

Possible Duplicate: How many genes do we share with our mother? I went to a lecture that talked about the behavior of social insects in terms of their relatedness of genes. For instance, ...
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Distinguishing Father from Brother

Given the (non-identical) DNA sequences of two men and the knowledge that the second man is either the father, brother, or son of the first man, is the DNA useful in determining which of these three ...
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How does the splicing enzyme recognize where to splice the introns?

When the DNA from the nucleus is transcribed to an mRNA, the mRNA is spliced by an enzyme before it goes outside through the nuclear pore. What is the name of this enzyme and how does it recognize ...
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How do eukaryotes terminate transcription? (clarification on Campbell Biology)

I'm having trouble understanding how eukaryotes terminate transcription. Studying Campbell Biology (pg. 342, 10th ed.), I read: In eukaryotes, RNA polymerase II transcribes the polyadenylation ...
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blastn: What substitution matrix is used?

I'm currently working aligning sequences, and I need to compute similarity between pairs of DNA 'words' of a particular length. For amino acids I am able to use the substitution matrices in Biopython ...
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Write the haplotypes of the family

I'm doing old exam assignments to prepare for my finals on Monday and I've stumbled on one assignment that I'm not sure how to tackle. A family with 2 children is examined for cataracts using PCR ...
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How do nicks in the DNA strand affect the success of Long Range PCR?

Long Range PCR using NEB Master Mix - Hot Start Taq was working fine for me (amplicon sizes of ~10kb) but stopped working all of a sudden. Is it possible that many freeze-thaw cycles on the DNA ...
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How do mosquitoes maintain telomere length?

While the vast majority of eukaryotic organisms maintain their chromosome ends (telomeres) via telomerase, an enzyme system that generates short, tandem repeats on the ends of chromosomes, other ...
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What is the genetic distance where linkage can be ignored?

I heard several times that two SNPs, that have at least 1'000 nucleotides between them, can be seen as 'unlinked' due to frequent recombination events. I also once saw a paper showing a graph "degree ...
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How do multiple replication forks function without 'colliding', and what is the benefit of this method?

I'm currently reading a little about DNA replication, and have come accross the following statement; Replication starts from a fixed point and is bi-directional ... In Eukaryotes, there are ...