Dna Definition and 374 Threads

Homework Statement Suppose we discovered a form of life like our own which utilized 20 amino acids, but had 6 nitrogeneous bases instead of the 4 our life uses. What would be the minimum length of a codon which could represent all 20 currently used amino acids? The Attempt at a Solution I...

Hi I'm debating a creationist and he makes the claim that no DNA can be added to a genome. Says there are no experiments. Can someone help me with concepts or sources to experiments? Thanks

Hi, maybe someone here could help explain this, I understand the concept of a nanopore; a graphene sheet with a hole burned in it, force DNA through it and measure the conductance to determine the base. But I'm unclear how micron sized beads help the process. Please find attached a slide from my...

Homework Statement A strand of length L begins life as all A's. Assume that each letter evolves independent of all the rest until today, 1000 generations later. Within each generation there is a ##\mu## probability that the letter mutates to either C, G, T. Finally, assume that once a letter...

Homework Statement I have a DNA sequence generated by L throws of a 4 faced die with probabilities ##\pi_A, \pi_C, \pi_G, \pi_T##. Each probability is unknown. Task: estimate the probability of each side of the die. Hint: use a random variable defined by the sequence that has a binomial...

I have one question about the history of the policies regarding DNA privacy the NIH has instituted. Simply, was there a particular study or research breakthrough that was the tipping point for instituting privacy measures? I just read an ethics paper called "Privacy and the Human Genome...

Homework Statement In a DNA molecule, the base pair adenine and thymine is held together by two hydrogen bonds (see figure below). Let's model one of these hydrogen bonds as four point charges arranged along a straight line. Using the information in the figure below, calculate the...

Hello, Some years ago I have heard from the brazilian physicist, Constantino Tsalis, that the DNA molecule, if unfolded and made to lay in a line, will be close to one meter long. But he said that thermodynamically this configuration could be taken as an impossibility, for no such long and...

I am referring to "3 parents baby" discussed e.g. here http://www.economist.com/news/leaders/21565209-new-technique-help-cure-mitochondrial-diseases-should-be-permitted-law-powering . AFAIU they take the egg of mitochondria donor, remove its nucleus / DNA and transplant into it the mother's DNA...

Hello, I notice that when DNA is replicated, it is split apart. This is the same as the start of transcription, however I suppose the difference is that DNA is replicated with DNA polymerase, and RNA with RNA polymerase. Do these two polymerases compete for a strand of DNA in order to do their...

DNA survives critical entry into Earth's atmosphere http://www.sciencedaily.com/releases/2014/11/141126144150.htm Full published article: http://www.plosone.org/article/fetchObject.action?uri=info%3Adoi%2F10.1371%2Fjournal.pone.0112979&representation=PDF

Hello, How is it that transcription occurs on the non-coding strand? If you are to code for proteins, wouldn't it want to do the transcription on the coding strand? This is puzzling me

Something I've always wondered about. It's neat to see a quantitative answer, finally. "To reach the new figure, Dr Lunter and his colleagues took advantage of the ability of evolution to discern which activities matter and which do not. They identified how much of our genome has avoided...

Hi there Is there anyone to help me about a definition of "DNA nano wire"?!

In cloning, they replace the cells nucleus, but what if you only have pure dna, could you somehow, switch it for the cells own dna?

Is it true that hair that is cut from your head (not pulled), does not contain any nuclear dna ? My understanding of hair structure is that it is a matrix with at least some dead cells present in various layers. Eg the outside cuticle is made of flattened cells . Feughelman, Max Mechanical...

Is there any research being done on using DNA or big long protein macromolecules as machinery for memory in computing? The ability to pack in so much information in a long string of protein because of how proteins can fold is vast. Has anyone proposed making DNA that into a binary entity, like...

Homework Statement The length of DNA helix occupied by one nucleotide pair is 3.4 A (angstrom). A human has 10^14 cells and each human cell has about 6.4 x 10^9 nucleotide pairs of DNA. What is the length of double helix that could be formed from this amount of DNA in a human individual...

is dna in a sexually reproducing organism one single chain with dna from one parent coming first,with the other parent's dna joining it as it ends.or do the two strands lie side by side,without joining.Or do they lie side by side and join at some point? the purpose of asking the question is...

Homework Statement Not exactly homework... "What are the uses of bacterial DNA replication in molecular biology?" The Attempt at a Solution Am I correct to say that 'the bacterial DNA replication process can be used to artificially create DNA that we desire and then use it for some...

So we are learning about vectors and how you can insert vectors into a plasmid and then that plasmid in a bacteria will make lots of copies of the protein that your sequence codes for. I don't understand how inserting the DNA that codes for a protein into a bacteria gives you just the protein...

I was reading an article on Pseudomonas syringae and how removing a gene called inaZ from it's DNA will allow it to be sprayed on crops to prevent the crops from freezing during the winter. How is the inaZ gene removed from the DNA? I'm thinking that they use restriction enzymes that cut out the...

Has anyone used a home DNA testing service? I was looking at 23andme service. The reviews are pretty good and it's only $100. Could be interesting. What do you experts think? Worthwhile?

May I know how to design the DNA chip? What are the basic parameter I have to consider? The DNA chip will be used in microfluidic chamber for cells analysis. Thanks zmp

I want to know what is happening at micro-level, how macroscopic tumbling of the solution can actually break a chemical bond?

Hello! I'm looking for information, articles and theories about which could have been the original molecule of life: DNA, RNA or protein. Most of what I've found is based on the RNA world theory (which I think is pretty well explained and sounds plausible), but I haven't found out any...

Recombinant dna technology-[how are specific genes chosen]?? IN recombinant dna technology,certain segments of dna are removed from one organism and put in another.How are are specific portions of DNA removed from certain animals and fused into others?? More importantly,how do scientists know...

i understand that methylation helps to differentiate between parental strand and daughter strand with mismatch nucleotides. (newly synthesised DNA is hemimethylated) then GATC endonuclease and GATC exonuclease will nick the mismatch nucleotide sequences. however, i don't understand how the...

How much variability exists between the genomes of separate individuals? What is an SNP?

http://news.yahoo.com/longevitys-secrets-sought-dna-100-olds-203909753.html Apparently, there's something good in their genes! "By the time you reach, say, 105, "it's very hard to get there without some genetic advantages," says Dr. Thomas Perls, a geriatrics expert at Boston University."...

I'm an italian high school student, and I decided to do an in-depth study about DNA computer as final-thesis, that we have to make at the end of our final high school year, and whose function is a sort of introduction to the oral exam. Now, my question is: where can I found useful information...

I was reading articles regarding to the changing of human DNA and how our DNA seems to evolving a rapid rate. With this I wondered if the human DNA does evolve? and if so would DNA gain traits that we would now consider super human? Any info in this area would be appreciated.

Hi, I'm really close to deriving something that many biology textbooks like to skip: the probability of a certain DNA molecule (base) remaining the same while it suffers changes both to and from the other 3 types of DNA molecules. This sounds specificially biological, but as probably a good...

How would a haploid chromosome dna look like?? how would a haploid chromosome dna look like?will it be a single strand of DNA from a single parent? or will it be 'bits and pieces',with gaps in between.the purpose of asking this question is i don't understand how haploid chromosomes 'fuse' to...

I have 2x10^12 unique sequences of DNA, and I have an average of 47 copies of each sequence (so 94x10^12 DNA molecules total). How many molecules do I need to choose at random to be "confident" (defined as you please) that I have at least 10^10 unique molecules? 10^11? 10^12? I would really...

How does rna polymerase "read" dna ?? How does RNA polymerase "read" DNA? What i mean is ,after all,the polymerase is just a molecular complex,not an intelligent organism?how does it "know" that it has to combine 'A' to 'U' and 'G' to'C'. What is the exact mechanism involved??

http://www.sciencedaily.com/releases/2011/03/110331104014.htm ScienceDaily (Mar. 31, 2011) — Do the principles of quantum mechanics apply to biological systems? Until now, says Prof. Ron Naaman of the Institute's Chemical Physics Department (Faculty of Chemistry), both biologists and physicists...

Hi all, If we find some fossils there, will we be able to tell if it's DNA-based? Similarly if we find fossils (or even current life) on Europa what is it likely to be based on? I'm very curious if extraterrestrial life is like what we have here on Earth or not. It seems clear that...

how does Helicase unwind the dna strands?what is the chemical Process involved?what is the chemical reaction?

Let's say an extraterrestrial space probe crashes into Earth and we recover from it a disk that we conclude contains a genome. Would we be able to tell anything about them from that information alone? What kind of experiments would you run on it?

I know DNA gives instructions for proteins, but is it information as in the sense that it was created by a conscious mind? What about biologists who say that DNA is information?

Hi there. First of all sory for possible grammar errors. I have searched this forum and haven't find this topic. I would like to know what do you think of it.http://www.popsci.com/science/article/2011-01/can-our-dna-electromagnetically-teleport-itself-one-researcher-thinks-so " Nobel Prize...

I asked this question in some other place but they had simply said that .. the DNA polymerase don't have the ability to start DNA polymerization but I already know that and it doesn't answer my question. RNA is not much different from DNA (virtually same as far as polymerization reaction is...

If I am to understand Y chromosome haplotypes correctly: Let's say that I am male. I have an X chromosome from my mother and a Y chromosome from my father. Because the Y chromosome is passed directly through my father's paternal line, does that mean I have more in common genetically with my...

what is Mechanism of DNA double from 1N to 2N ?

Homework Statement How does a large DNA molecule enclosed in the nucleus of a cell? The Attempt at a Solution I know it has to do with histones and how DNA winds twice around it to make it shorter, but can anyone further expand on this? Thanks : )

Hi I am not from biological background and I seek simple explanations for the above (genes, chromosome and DNA) I know plenty of material are available in net, but if some one explains me what they are and how they are connected in essence I would be grateful to him. These terms are repeatedly...

The purpose of meiosis is to create genetic variation unattainable through mitosis by, in effect, randomly replacing one homolog from each homologous chromosome pair with another one from a different individual. There is also an exchange of genes between homologs before this replacement occurs...

1. A. E.coli DNA ligase can act as a DNA gyrase in the presence of high concentrations of AMP. Explain. B. Would you expect the E.coli ligase/AMP combination to resemble type I or II topoisomerase, or neither. Justify. C. Would you expect human DNA ligase to act as a topoisomerase in the...

Can DNA adopt an A-form helix, and can RNA adopt a B-form helix. If so, under what conditions, and if not, why not? The only idea I have so far is that low humidity will help form the A form, and high humidity forms the B form. However, can humidity change in our bodies? I'm lost here.