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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DNA. mRNA, tRNA [closed]

Can someone explain to me how transcription and translation works, especially the part about codes. And does amino acids has code or is it the tRNA?
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Would it be possible to eat things from another planet [closed]

Although at first glance my question is perhaps better suited for a space exploration or sci-fi forum I looked and felt this forum was more appropriate. What makes plants and animals edible and ...
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Do all cells produce the same proteins?

If DNA is more or less the same in all cells, and DNA is used to produce proteins from aminoacids, then do all cells produce the same proteins or are they specialised/controlled by something?
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What is the length of the centromeric repeat sequence in a human?

I'm looking for the lengths of the centromeres of human chromosomes. The best I could come up with so far has been: The length of individual centromeric arrays was found to range from an average of ...
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How to calculate information content of a DNA sequence

How does one calculate the information content of DNA sequence like ATCGGCT where mutation rate of G's is 10% and the most common mutation product binds with C and A with equal frequency. I know that ...
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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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enzymes that stabilize DNA loops

As a follow-up of a previous question, I would like to know what enzymes or protein complexes have been used to manipulate DNA samples into stabilizing DNA loops. I have read that cohesin is one of ...
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Choice of primers for PCR

This exercise was given by my professor but I am struggling to understand the solution. A PCR is performed on the following sequence (in order to replicate the chain and thus have a greater quantity ...
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How did the first life form on Earth reproduce without DNA?

How did the earliest life forms exist without DNA? The most likely scenario I can think of for life happening from nothing is that, over billions of years, with trillions of water molecules and dust ...
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DNA to Binary Distance Computation [closed]

If I represent DNA as binary values, what is the best way of computing distance between them. So : A = 00, T = 11, G = 01 and C = 10 Hamming Distance between ATGC and TAAC is 3, however their ...
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How to safely conserve my current DNA methylation marks?

I read the Wikipedia article on DNA methylation Let's say I want to extract and then stock my current DNA methylation marks somewhere so that I can use it safely 20 years in the future for a medical ...
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Making a offspring with O+ blood [closed]

If offspring is O+ what blood type would parents have to have to make this possible?
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Why do we encode information in DNA in binary and not in base 4?

I recently read an article about Harvard scientists encoding 700Tb of data in DNA strands. But they encoded the information in base 2, so T and G was a 1 and C and A was a 0. But why binary? Why didn'...
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Does cancer cells come from same process as evolution? [duplicate]

Here is how I understand it: DNA replication is not 100% perfect and error can happen, this error can be good(evolution) or bad(cancer properties). But its not the only source of cancer cells - DNA ...
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How to read this DNA inversion diagram?

In the following diagram about chromosome inversion, I don't understand: Why do we need to take the reverse complement from step 1 to 2? Isn't inversion just reversing the bases in the region? How ...
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Do apes and humans share 99% of DNA or 99% of genes? What is the difference?

I made an answer on the Scifi.SE that can be read here. It is about how the characters in the story Jurassic Park might have gotten DNA for all the species shown. In my answer, I said this: Apes ...
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Do plants have distinctive DNA genomes from each other like humans do?

Can exact same species of plant have a distinct genome from others of same exact species growing nearby or in a different place/country etc. ? Can a leaf be traced to the the exact plant based on DNA ...
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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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How do we know that everybody's DNA fingerprint is unique?

How do we know that everybody's DNA fingerprint is unique? I know, I know, everybody's DNA is unique. But when we do DNA fingerprinting, we're looking at very specific regions of high variability. ...
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What is the meaning of the “d(…)2” notation when writing a DNA sequence?

When the sequence of a DNA oligo is written as d(CGCTAGCG)2 what is the meaning of the d(...)2? Why would it not simply be ...
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How much of the Neanderthal genome is living on in humans?

I've understand that outside of African, most ethnic groups carry some (4% or less) Neanderthal DNA. So en masse, across all living humans, what percentage of the original Neanderthal genome is still ...
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In percentage, how much is the human genome (DNA) similar to the mouse genome?

Some guy argued with me against evolution theory, and he claimed that human and mice share 98% just like human and chimpanzee. I've tried to search online for a simple and accurate answer, but I ...
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1answer
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Questions on adding a protein to a DNA library [closed]

Two questions regarding finding the DNA sequence of a amino acid sequence (AA): 1) If you are able to find out the mRNA sequence of an AA, then don't you automatically know the DNA sequence? 2) ...
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Why does Taq polymerase add 3' adenine overhangs?

Is there a mechanism for the preference of Taq polymerase to add a non-templated 3' adenine (overhang) instead of other bases?
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can you tell someone's age from a DNA sample? [duplicate]

So as I understand it telomeres shorten as you age. Working under that assumption.. let's say you were investigating a crime and there was some DNA evidence that had been left behind. Could you ...
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Minichromosome maintenance protein structure and function

I am having difficulty answering three homework questions which relate directly to Chong et al. (2000). Questions The authors have determined that MtMCM is able to bind both ssDNA and dsDNA (see ...
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How Did They Know What To Do ? And Cellular Identification [closed]

So this is regarding Science, generally, it has influence throughout each section science. How did the early age Scientists etc. knew what is to be done to achieve a certain thing ? And by that, I ...
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Mutagenic Agent [closed]

This was a passage in University Degree Genetic Journal that confused me. DNA base pairs are more susceptible to mutagenic agents, so this reduces the chances of spontaneous mutations happening ...
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During the process of correcting mutations via gene therapy, is the defective gene removed?

Just recently started learning about gene therapy, many websites explain that the corrected DNA can be added to the genome using a vector and all that. I just don't understand what happens to the ...
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Determine OTU identity using Blastn full database or organism specific database?

I am seeking opinions on the best way to determine OTU identity using Blastn. Would the best way to identify an OTU be to blast the OTU to the full nr/nt Nucleotide collection or to blast your OTU to ...
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What is two-start or zigzag model of 30 nm chromatin fibre?

I read some webpages describing the two-start model but could not get it. I'll be obliged if someone helped me understand the topic. The websites I have been through are: 1.http://www.nature.com/nrm/...
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Strand directed mismatch repair system?

In SDM (strand directed mismatch repair), random correction of DNA (correction of template strand) is not right. For example if G (from template strand) gets joined with the T (it should have actually ...
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Construct a restriction map of a linear fragment of DNA using the following data?

I've attempted to do the single digests, and the double digests, but cannot complete the map.... I've attached what I've done so far DNA Sizes of Fragments (bp) uncut DNA 900 DNA cut with EcoRI ...
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How many Watson-Crick + Hoogsteen triple base pair combinations are there?

Are these triple base pairs the only Watson-Crick + Hoogsteen triple base pairs possible? Furthermore, are TAA and TAT mixed up? This image is from Wikipedia, so it's possible that it's erroneous.
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Do eukaryotes assimilate DNA that is floating in the extracellular membrane?

Prokayotes, which replicate primarily using binary fission, don't get much genetic diversity. For this reason, they take in any genetic material they encounter, in a gambit to help them better adapt ...
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Why don't housekeeping genes have TATA Box regions in their promoter sequences?

Housekeeping genes are genes that are continuously transcribed. Like all other genes they have promoter sequences, but they don't have TATA box sequences that are used to specify from where ...
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DNA binding Domain [closed]

How to say whether a specific amino acid in a protein is binding to DNA or not from sequence alone and what are the features or characteristics to be considered?
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How do the major and minor grooves in the DNA helix arise?

I understand that they arise due to the pairing of bases of two opposite stands and are sites through which important proteins needed for replication and transcription of DNA interact. But I don't get ...
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What is positive and negative supercoiling?

Is the following correct? Positive supercoiling = the coiling of DNA helix (B-DNA) on itself during intesified coiling of the two DNA stands in right handed direction negative supercoiling = the ...
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BWA-MEM single strand or doublestrand alignment

In whole genome secondary analysis does BWA-MEM use a double stranded fasta reference or are reads aligned to only one, single stranded fasta reference?
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Does DNA polymerase I require a $3^\prime$ end?

DNA polymerase III adds nucleotides in the $5^\prime \rightarrow 3^\prime$ direction because it can only add nucleotides to the $3^\prime$ end of the previous nucleotide. This is why it requires a ...
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Hydrogen bonding and the blocking thereof in nucleic acids during nuclear processes

In transcription, RNA polymerase unwinds the DNA double helix and begins attaching RNA nucleotides to the template strand. In its wake, the DNA double helix closes back—this is only natural, seeing as ...
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From DNA to final traits of microorganisms? [closed]

From the answer of this topic, could someone indicate me a book or article about how DNA set the phenotype of microorganisms? For example, showing how DNA changes the shape of such a cell or how DNA ...
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1answer
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DNA Topology. Question on twists and writhes

Hi guys there is a question which has been driving me crazy ever since I saw this video(https://youtu.be/az2c6UbEdug). At 4:50 the guy says that when a right-handed circular DNA starts forming a right ...
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Color of DNA, available absorption energy levels of DNA molecule, mutations

I have done a couple of DNA separations and observe that the clumped strands of DNA are white. Is that an artifact of the chemicals used in standard separations? Or is it indeed the case that the DNA ...
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Is Chargaff's rule really applicable?

Chargaff's rules states that DNA from any cell of all organisms should have a 1:1 ratio (base Pair Rule) of pyrimidine and purine bases and, more specifically, that the amount of guanine is equal to ...
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Getting PCR amplification at annealing higher than Tm!

I am amplifying a gene where in a gradient pcr i am getting amplification at an annealing temperature about 5 degrees (67) higher than Tm (62.5)? What is wrong here? Also, I am getting a very strong ...