Questions tagged [dna]

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

Filter by
Sorted by
Tagged with
1
vote
1answer
20 views

A question about dna triplex

Short DNA triplex strands have been identified in various organsims. But, would injecting a single strand of DNA or RNA (with its bases complementary to the bases of DNA found in the major groove of a ...
7
votes
2answers
3k views

What is the instructional language of DNA?

DNA carries most of the genetic instructions used in the development, functioning and reproduction of all known living organisms and many viruses (Wikipedia). Is it already know how ATCG's sequences ...
5
votes
1answer
4k views

Finding exons in DNA problem

My attempt: I looked for the TACs because I thought this would be AUG in mRNA and ultimately Methionine (the start codon). But apparently, that's not how you do this problem. Im confused because the ...
0
votes
0answers
18 views

How to measure DNA concentration from Acetonitrile Cell Lysis of plant cells?

I'm currently trying to normalise my data to the number of cells present in each sample. Currently, I lyse the cells with cold ACN and centrifuge. The supernatant contains what I'm interested in, and ...
0
votes
1answer
123 views

Is it possible to fuse DNA from two sperms into one sperm?

Is it possible to fuse the DNA of two genetically different sperms into one singular sperm? In theory, half of the number of chromosomes in a normal sperm would come from one sperm and the other half ...
3
votes
1answer
145 views

Explain to a layperson how cigarettes smoke might cause cancer

I have a very intelligent friend who is a light smoker, and also a Biology layperson. I wondered whether understanding exactly how cigarettes smoke can cause cancer, might encourage him to smoke less ...
1
vote
0answers
44 views

Changes in DNA and forensic cases

If DNA changes over time, how is it that forensic DNA gathered decades ago can be matched to a person today for solving crimes?
0
votes
1answer
42 views

How to calculate the quantification of qPCR to the equivalent of the number of nuclei in fungi?

I have a question about the quantification through qPCR. The my question is: if I made the qPCR of a fungal functional gene, how is possible to obtain from the quantification number (in nanogram) the ...
0
votes
0answers
28 views

How much DNA can differ among different humans today?

According to this article, Australian aborigines carry unknown DNA Australian Aboriginal people carry the DNA of an unknown human relative. This made me wonder, is it known how much DNA can differ ...
1
vote
1answer
51 views

How hard is it to build a promotor in a DNA that initiates DNA transcription when specific hormones are around

I have an idea that you could find out which substances are within a sample in vitro that you are investigating by creating DNA that has a bunch of different promotors for different substances you are ...
1
vote
3answers
71 views

Is it possible to distinguish between coding and template strands from the sequence?

Let’s say you have the following DNA sequence fragment: 5’-ACCAGTACTTCGT-3’ 3’-TGGTCATGAAGCA-5’ Is there any way to determine which strand is the template ...
7
votes
1answer
105 views

A little help understanding DNA supercoiling

I am studying molecular biology from Lewin's Genes XII and got confused in the supercoiling topic. Since then I read from several other sources and so far understood the following. However, I can't ...
-7
votes
1answer
80 views

Is the total of all human DNA (23 pairs) the longest of all species?

The human DNA molecule is about 2 meters in length. See here. We have 46 of them, so in total 82 meters. In this article it is said that the genome of the Protopterus aethiopicus (a.k.a The marbled ...
-2
votes
0answers
44 views

Is our data about DNA purely empirical?

I was curious about what makes some things living. The concept of a virus prompted me to think about that. I read that a virus is a very simple organism with only DNA in it. This DNA is the "...
0
votes
1answer
44 views

How would two SNPs interact to affect CYP3A5 gene activity?

If someone has a non-functional rs41303343(T;T) SNP, yet that individual also possess the partially functional rs776746(A;G) SNP, is their CYP3A5 genotype functional or nonfunctional? In other words, ...
2
votes
0answers
56 views

What is the charge of (bacterial) ribosome?

Ribosomes are negatively charged and thus electrostaticaly repelled from DNA. However, I could not find a good reference that would allow me to estimate the magnitude of negative charge on a ribosome. ...
1
vote
1answer
45 views

How to convert enrichment/depletion to frequency for comparing deep sequencing to sequence profile?

I have two datasets, from different sources, that I need to compare. The first set is deep sequencing results of a directed evolution experiment, where I have the naive library and selected library ...
3
votes
0answers
69 views

Why does absorption (at 260nm) of ssDNA increase with temperature?

In the graph below, I understand why A260 of double stranded DNA would increase with temperature increase, as more of the DNA becomes single stranded (and A260 of ssDNA is higher than that of dsDNA ...
3
votes
1answer
63 views

Design rules for DNA linkers

I want to use double stranded DNA linkers to physically bind two "things" together, by grafting ssDNA on each one of them and using DNA hybridization as the locking mechanism. I do not expect the ...
2
votes
1answer
54 views

probability of hairpin vs self-dimer formation?

I have a linear ssDNA oligo that is designed such that the ends are complementary, and conducive to hairpin formation (see attached figure). My question is, which has a higher likelihood of formation, ...
0
votes
1answer
350 views

Heat shock vs electroporation

I've been transforming E. coli via heat shock in order to insert oligonucleotides (around 50 nt); however, none of my experiments have given positive results so far. I begin to question the efficiency ...
2
votes
0answers
55 views

How to calculate percentage of DNA that ancestors contributed?

In David Reich's book "Who we are and how we got here" there is a graph explaining that more we go back in our ancestors generations, the least we have chances to have any DNA inherited from one of ...
1
vote
1answer
71 views

Significance of the resequencing of the chimpanzee genome

Introductory remark: I am not a biologist, but a somewhat knowledgeable layperson. I have been told that sequencing of chimpanzee DNA until recently has been done almost exclusively using human DNA ...
0
votes
0answers
36 views

What's the transposon difference between chimps and humans?

I was reading that humans and chimps share 98-99% of the same DNA sequence but I also read humans and chimps only share around 20% of the same proteins. Also, 45% of the human genome is transposable ...
-3
votes
2answers
56 views

In theory, could a woman that has fathers and mothers cromosome identical, be able to live?

What Im getting at is something totally impossible, but im making some mental experiences. Assuming I have a machine that can produce a living being just from a DNA code (like in the movie The Fly)....
1
vote
1answer
21 views

Which DNA polymerase can use a nick as priming site?

Which DNA polymerase (commercially available) can initiate polymerization at nicks, without a standard primer? My goal is to perform rolling circle amplification starting at a nick.
2
votes
2answers
126 views

How to find the amino acid in the DNA protein

3' A T A G T A C C G C A T G T A C G G G C G A G A C A T T C G A G C A T T C A T 5' This a Template DNA. How to find the number of amino acids amino acids ...
0
votes
1answer
53 views

How to design a permanent vaccine to cholera using CRISPR?

I know that Vibrio Cholerae infects the body through the GM1 ganglioside. So, would it be possible to engineer a CRISPR gene editing tool to prevent Vibrio Cholerae from getting into our cells? ...
0
votes
2answers
69 views

DNA described somewhere?

This is not purely biological question but how do the companies making DNA analysis know what your DNA means? Is there some database describing human DNA? I watched some documents about DNA, gene ...
0
votes
1answer
64 views

From DNA data, is it easier to conclude that chimpanzees are our close relative, than it is to do a paternity testing?

Well, today I was contemplating on how to explain evolution, approaching with the dialectic method. When it came to why chimpanzees and us being so close in the tree of evolution isn't outright absurd,...
0
votes
2answers
68 views

Can something cause both breaks and cross-links in DNA?

A double strand break in DNA is exactly that: the strands of DNA are severed. A cross-linkage occurs when something forms a covalent bond between two nucleotides in DNA. However, is it possible for ...
1
vote
2answers
60 views

How do mutations and protein synthesis link to cancer?

How do mutations and protein synthesis link to cancer? I know that a mutation in DNA can cause the triplet code on the mRNA to change so different amini acids are made and a different order means a ...
7
votes
2answers
2k views

Isn't biological immortality strictly speaking impossible?

This question relates to both immortal cells such as cancers and organisms like the Hydra genus. Isn't it technically impossible for these "immortal" biological systems to live forever, even ...
0
votes
0answers
57 views

DNA of Different Species and The Fossil Record of Their Common Ancestor

Let me please be clear about something. I believe in evolution. The evidence and data are compelling and conclusive which makes it a very well-established theory. I'm seeking a certain evidence (if ...
-1
votes
5answers
121 views

What is the fundamental difference between human genome and other genomes that makes human a self-conscious living organism?

DNA is considered to be the blueprint from which any organism can be created. DNA carries the genetic information to construct a living body. DNA carries genes which represents the information that is ...
2
votes
1answer
63 views

Taq Polymerase's stability at high temperature

I was asked a question as to what is so special with Taq Polymerase that makes it quite stable at high temperatures though its functioning is the same as other DNA polymerases like that of mesophiles. ...
1
vote
1answer
108 views

What do lower case nucleotides mean in this gene sequence?

The following table (image linked below) shows promoter sequences recognized by different sigma factors. The sequence given for, e.g. sigma B is "GTTTaa"; why are the "a"s lowercase? (from "A sigma ...
3
votes
1answer
72 views

Are there any ways to force DNA-origami to create a geometric shape from non-nucleotides (not from DNA)?

I mean, can we create with the help of DNA-origami figures that would not consist of DNA, but, for example, carbon? Is it even possible?
34
votes
2answers
14k views

What is the advantage of circular DNA in bacteria?

From what I understand, bacteria have circular DNA. What advantages does it have over linear strands like for eukaryotes? Do there exist bacteria with more than one ring of DNA?
0
votes
0answers
56 views

How much DNA (or genes) do homo-sapiens and ursus arctos (brown bear) share?

How much DNA (or genes) do homo-sapiens and ursus arctos (brown bear) share? There are articles online that indicate that humans share xxx% of DNA with Chimpanzees, bananas, and other assorted ...
3
votes
1answer
83 views

Why do we need to amplify DNA sequences?

I am learning about biotechnology. I have no education in biology or chemistry and am simply interested in the subject of biotechnology. I am wondering why we need to have multiple copies of a piece ...
2
votes
2answers
3k views

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 ...
2
votes
3answers
1k views

How does high-fidelity of DNA replication depend on the formation of hydrogen bonds?

Replication has an error rate of less than 1 in 100 million. DNA polymerase forms H-bond with the H-bond acceptor atoms in the minor groove. <-- enhance fidelity here? Binding of the triphosphate ...
6
votes
2answers
31k views

Difference between CDS and cDNA

What is the difference between Coding Sequences (CDS) and cDNA? Are Coding sequences the sequences that is transcribed to mRNA and cDNA in contrast DNA obtained by reverse polymerization of matured ...
0
votes
2answers
105 views

Does it make sense to make my own DNA copy (kind of backup) while I am young?

As I understand, when I am getting older DNA becomes more and more damaged in my body. Does it make sense to make my own DNA copy (kind of backup) while I am young (38 years old or for my kids) in ...
5
votes
1answer
407 views

Do telomeres appear at just one end of the chromosome?

I have just studied DNA Replication for my Biology Class and I have this question that leaves me stuck, though I have tried to figure it out myself. During telomere replication, I am aware Telomerase ...
1
vote
1answer
74 views

During DNA foot-printing, what is the purpose of radioactively labeling only one end of the DNA fragment?

I read that during DNA foot-printing analysis, DNA is radioactively labeled on one end before being cleaved by DNase 1. I understand that it is labeled so in order to locate the fragment on a gel, but ...
0
votes
1answer
49 views

Klenow amplification

Am I correct in thinking that in a standard probe synthesis reaction where primer/template are heated up and then cooled down for Klenow to extend, the theoretical maximum amplification is doubling of ...
2
votes
2answers
827 views

Is DNA a single molecule or 46 separate pieces (out of 23 chromosome pairs)? [duplicate]

It seems that biology books refer to DNA as 'a' molecule (implying that it is a single continuous uninterrupted double strand) ... but in those same books chromosomes are depicted as 23 separate ...
0
votes
1answer
210 views

Why does deamination in the lagging strand lead to an increase in the relative number of guanine and thymine to cytosine and adenine?

My question arose from this article on Wikipedia on the GC-skew in bacterial genomes: https://en.wikipedia.org/wiki/GC_skew As far as I understood, the lagging strand (the template strand), during ...

1 2 3 4 5 22