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DNA is a chemical, and therefore, its interactions are governed by its shape. There is no way to look at a DNA sequence and know all the ramifications that changing a letter will have on its shape. I could tell you that changing the first two or last two letters of an intron are highly likely to destroy a splice site, but you can't make hard and fast ...


1

This isn't a question with a really well accepted answer yet, and comes up quite a lot in e.g. studies of population variation in transcription factor motifs. Usually, we approximate the sequence preferences of a DNA-binding protein with a position weight matrix. A weight matrix will given you a score for two sequences, so the simplest means of quantifying ...


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DNA is not made of these blocks only. But the genetic information is conveyed through the series of these four block. All animals, all plants, all fungi, all other eukaryotes, all bacteria, all archea and plenty of viruses use these four blocks. Some viruses use RNA instead of DNA, in which case the T is replaced by a U (Uracile). You will find more ...


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Why DNA for the genetic material? I think the correct and sufficient answer to this is the one so frequently repeated that it is difficult to find the original source. For example, G.F.Joyce wrote in a 2002 Nature review article: The primary advantage of DNA over RNA as a genetic material is the greater chemical stability of DNA, allowing much larger ...


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It is false, because DNA synthesis occurs via DNA polymerase,5' to 3' By hydrolyzing activated nucleotides together. This occurs by nucleophilic attack of 3'-OH, of the last nucleotide in sequence, on alpha phosphate of a corresponding nucleotide triphosphates.


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Absolutely! The only limitation animals face on eating substances or objects is the size of the opening to their oral cavity, so if there is something on another planet that will fit in your mouth then you can definitely eat it. Whether one would be able to derive energy from the exo-material is an entirely different question.


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Short Answer- No, chances are negligible. Long Answer- Digestion is a chemical process which is mediated by enzymes. Enzymes are highly choosy molecules so that they only perform the work they're made for. In digestion, enzymes like proteases (for breaking down proteins), lipases (for breaking down lipids), amylases (for breaking down starch), DNAses (for ...


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if you sequence deep enough and add single-cell sequencing you will also find cell to cell differences in the DNA which will add an other layer of heterogeneity in protein expression between cells.


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No specific length for centromeres. Actually in a real chromosome in a cell, centromeres are usually very condensed sequences of DNA, they are winded and folded (if you know about the DNA structure). Thus you cannot measure the length of the centromere unless you decondense the chromosome first.


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I'm not quite clear what the question is asking, as far as I can see, one pair would be enough.. Since your primers don't include the distinguishing base (and it would be dicey to e expect a PCR reaction to totally fail because of a one base difference) I assume you are going to do sequencing or digest after the PCR to distinguish between the species?


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You do need two pairs of primers one unique to each species as you need a positive result to be confident that the thing you are looking for (cow or horse) is there. There is no limitation on them being in the same place (with a different last base). Usually this would be analyised by gel-electrophoresis and not by sequencing so you don't have to worry ...


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Well another (and less popular) theory called Panspermia says that life, actually, came from space, it was not originated here in earth. So this completely change everything, because the conditions where life would have been formed could be very different from our's planet, so we can't make any predictions with this considerations in mind. But thinking in ...


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Here is the results summary of the study that describes the discovery of DNA:RNA hybrid virus: Results Bioinformatic analysis of viral metagenomic sequences derived from a hot, acidic lake revealed a circular, putatively single-stranded DNA virus encoding a major capsid protein similar to those found only in single-stranded RNA viruses. The presence ...


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Short answer Before the RNA world, mineral surfaces may have facilitated the prebiotic containment and organization of biomolecules. Minerals are believed to have promoted the transition from a dilute chaotic prebiotic “soup” to highly ordered local domains rich in key biomolecules. Background As pointed out by others, the transition from a hereditary DNA ...


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So earth is estimated to be around 4.5 billion years old, and life has existed for about 3.4-3.9 billion years of that, around >75% the time. For a little perspective, Homo sapiens have been around for up to ~250,000 years, just 0.00005% of the time earth has existed. In that time the earth has changed massively, early earth was pretty hostile, but that ...


3

You can do without DNA, you need RNA to make proteins. Living organisms create and maintain a bubble that is very far removed from thermal equilibrium. So, you can speculate that at the origin of life, conditions existed where processes that are far from thermal equilibrium could still occur naturally without the support structures one finds inside living ...


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I am reluctant to answer with code, but it seems that the community decided that was an appropriate question for Biology.SE. So here is my solution. The idea is to "compress" the two bit that represent each nucleotide, such that each nucleotide will contribute 0 or 1 (not more) to the distance. You could use binary operations to do something like this ...


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Protein expression in cells is majorly governed by a concept called RNA splicing. This also forms the basis of different types of cells which has different proteins expressed at different levels, but from the same nuclear material: DNA, which can be visually seen here. Differential splicing leads to various isoforms of the mRNAs, which are precursors of ...


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This encoding doesn't make sense as nucleotides are not in the Hamming space. Hamming distance between every two nucleotides is constantly 1, but in binary encoding, it varies from 1 to 2.


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The best way is to choose a distance that represents what you want it to rather than necessarily relying on the Hamming distance. If you simply want base-by-base difference then calculate that (this may help) but you may also want a difference that depends on the likelyhood of mutating between different bases in which case you want to define a function that ...


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Each cell will indeed have the same DNA sequences and ability to produce any given protein. However, there are certain factors (transcription factors) and cellular conditions within a cell that dictate which proteins are produced. If the conditions are right then only certain proteins will be produced depending on what type of cell it is. This process by ...



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