Episode #125 of the Stack Overflow podcast is here. We talk Tilde Club and mechanical keyboards. Listen now

Questions tagged [molecular-biology]

The study of the molecular processes underlying life.

Filter by
Sorted by
Tagged with
-1
votes
0answers
36 views

Grade 10th Course topics [closed]

Could somebody please point out to me the main Biology topics that students in grade 10th and 11th need to study throughout the term, (for what concerns the UK school system, IGCSE exc.)?
1
vote
0answers
37 views

Can enzymes be modeled using classical mechanics?

When enzymes interact with substrates (i.e. a small ADP molecule and the much larger ATP synthase), does quantum mechanics play a significant role? Or can the interactions be relatively accurately be ...
-1
votes
0answers
38 views

Do we actually know the Huntington chorea molecular mechanism?

I mean, did we know all genes involucrated on the dynamic mutation, and the protein that are used or it will be affected? I found this paper on chorea genetics from 2016 where literally concludes: ...
0
votes
1answer
31 views

What would be the effect of excess taq polymerase on the PCR?

I just had one question regarding the possible effect of putting to much Taq polymerase in my PCR tube? Instead of 5µl I put 50µl (10x more). Do you think it will have a bad effect on the reaction??...
2
votes
1answer
52 views

Where does the number 67 in the nuclear protein/antigen Ki-67 come from? Why not 66 or 68?

I have read in in the original paper that in the year 1983 a research group in Kiel, Germany (that's where the Ki- in the name comes from) developed monoclonal mouse antibodies against Hodgkin ...
0
votes
0answers
19 views

Are human cells tetraploid during cell division?

If human cells are diploid, and DNA replicates before cell division, does it mean that our cells are tetrapolid for a short period of time (DNA replication - cell division). Photos of chromosomes are ...
-2
votes
0answers
14 views

PVP in buffer CTAB in DNA extraction

I wanna know if I can add pvp at the biginning of the buffer with the other solution or I have to used prior the extraction?
1
vote
0answers
47 views

Fluorescence assays to identify protein concentration without adding a large peptide sequence?

I'm trying to find a way of tagging a protein with something visually quantifiable to track protein concentration through potential purification steps and screen for the most efficient such steps. ...
2
votes
3answers
989 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 ...
1
vote
1answer
58 views

Ligation without purifying insert

I am planning to insert a 45 bp sequence in a vector. After restricting my insert to create compatible sticky ends, I am finding no way to clean it up. Is there any way for cleaning this fragment ...
8
votes
2answers
2k views

What stops messenger RNA from binding to itself?

Since mRNA is single-stranded, and (mostly) floats freely within the cytosol, what stops it from folding onto itself (like DNA) and preventing transcription?
5
votes
1answer
64 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 ...
0
votes
0answers
8 views

Methods: Homologous recombination and retroviral infection

I'm looking for a textbook that explains these methodologies: Use of homologous recombination to insert a gen-cassette into another organism's gen. Use of retroviral transduction to deliver genes ...
1
vote
1answer
33 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
0answers
16 views

How to map A single N1-methyladenosine (m1A) by primer extension?

I want to map a single N1-methyladenosine (m1A) modification by primer extension. I have silenced a gene which is responsible for guiding modification of m1A then I confirmed the silencing. My next ...
0
votes
0answers
24 views

Relevance of old atomic theory in understanding biology?

I have seen the explanation of many biological reactions using the high school atomic theory (I don't remember the name but it involves using lewis dot structure). So is it the case that the effect of ...
0
votes
0answers
12 views

How do I prepare a Basal medium for autotrophic mutant creation

Minimal medium (MM) was prepared by adding 2.0 g sodium nitrate (NaNO3) to 1 L of basal medium (BM) fol- lowing Correll et al. (1987). Chlorate resistant sectors (CRSs) were generated on two media i.e....
0
votes
0answers
17 views

Nutrition and experimental biology

We know that food in the stomach is present in the form of chyme treated with pepsin and hydrochloric acid, if we take food crush it with saliva and then treat it with Pepsin and HCl (in the lab),and ...
-3
votes
0answers
25 views

Types of bonds in protein chains?

I'm trying to understand possible bonds on the protein backbone. There are a lot of hydrogen bonds and sometimes disulphide bridges. Are both of these non-covalent bonds? I've read that we also have ...
15
votes
7answers
5k views

Online Molecular and Cellular Biology Video Lectures?

I am looking for video lectures to go through to guide my reading in intro molecular and cellular biology. I've had intro bio and I study evolutionary theory, but my molecule- and cell-level knowledge ...
2
votes
3answers
3k views

Book Recommendations: GRE Subject Test In Biochemistry, Cell And Molecular Biology

There are probably a lot of really good answers that may vary significantly in terms of content. I'm looking for a set of books that I can read in preparation for the GRE Subject Test In Biochemistry,...
0
votes
0answers
11 views

what is minimal promoter and what is basal promoter?

what is minimal and basal promoter and what are their elements and what is the difference between the two?I'm confused. searched a lot, but didn't found any satisfactory answer. please help
0
votes
1answer
26 views

Which one is better to use for water stress experiment GWAS or RNASeq?

This is my first time in this area of research. I am working on 95 varieties of bambara groundnut. I have done the agromorphological characterization of these varieties as well as the genetic ...
3
votes
1answer
296 views

Why is the Tm defined as the temperature at which 50% of dsDNA has changed into ssDNA?

In molecular biology, Tm is defined as the temperature at which 50% of dsDNA is converted to its single stranded form. Intuitively it would seem that the melting temperature should have been defined ...
1
vote
1answer
34 views

What causes the elongation of Genome down the evolutionary time line [closed]

Theory of natural evolution says that complex life forms arose from simpler ones e.g. starting from Eubacteria to modern day multicellular eukaryotes. {If we try to reduce these changes happening at ...
1
vote
4answers
90 views

Why do mutations not take place in mRNA of higher eukaryotes?

Is it because it is too short-lived to be mutated? Both DNA and RNA are nucleic acids so how is mRNA protected? RNA viruses undergo mutations to evolve so I guess it is not immune to mutations
0
votes
1answer
77 views

Viral RNA to DNA

I have a question concerning reverse transcriptase. Why is it that when the viral rna is converted to viral dna( as in the case for hiv), the virus develops resistance to medicine? Under what ...
2
votes
1answer
53 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 ...
18
votes
2answers
3k views

Why do specifically bananas go brown quicker in the fridge?

Perhaps the title should be: Why don't all fruits containing phenol residues go brown quickly when left in the fridge? Bananas go brown over time because of the oxidation of phenol residues. ...
0
votes
1answer
54 views

What are the uses of Helical Wheel Projections in Structural Biology?

I have seen helical wheel projections used to illustrate amphipathic helices in proteins. Are there any other uses for these models?
0
votes
1answer
19 views

What is an acceptable qPCR efficiency when adjust using the Pfaffl equation?

I have efficiencies of 76% and 85%. THis is clearly below what is normally acceptable. But the pfaffl equation corrects this, doesnt it? However is it acceptable to publish this data?
-1
votes
1answer
37 views

Which are more beneficial: lyophilized or hydrolized collagen peptides?

Looking at two different manufacturing methods for collagen peptides: hydrolyzed vs lyophilized (freeze dried), I read that hydrolyzed results in a hydrophobic biolayer molecule collagen peptide. Re:...
14
votes
3answers
9k views

How does the body switch between aerobic and anaerobic respiration?

Lets take the case of a person doing heavy exercise. Aerobic respiration is taking place, but oxygen is about to be finished up. Glycolysis occurs, Krebs cycle finishes. Now NADH and FADH2 enter ...
0
votes
1answer
43 views

What is the difference between protein and peptide? [closed]

On which basis do protein and peptide are divided? I mean which factors differentiate them?
14
votes
1answer
95k views

Why do we add salt when precipitating DNA?

All the DNA extraction protocols I have seen involve adding salts to the extraction buffer. What is the purpose of the salts? What happens if they aren't included?
3
votes
1answer
124 views

Why is it thought that protein folding is determined solely by amino acid sequence?

It seems that it is a generally accepted idea that protein folding is completely determined by the sequence of amino acids, but why do people believe that? Is it simply that no example of a protein ...
7
votes
1answer
216 views

Does depolymerisation take place at the minus end of microtubule?

Wikipedia says that Dynamic instability refers to the coexistence of assembly and disassembly at the 'ends' of a microtubule. but Karp's Cell Biology, 7th edition says Dynamic instability is ...
1
vote
2answers
54 views

Software to model and analyse protein–ligand interactions

I am currently trying to model a certain protein (Golgi Mannosidase II) and compare the induced fit of the inhibitor swainsonine. I would like to be able to analyse the distances between bonding ...
2
votes
1answer
92 views

Why replication collapse but not stall leads to DNA break?

I have been looking into the concept of replication dynamics and was wondering why collapsing but not stalling leads to a DNA break.
0
votes
0answers
25 views

E. coli & aspartate

I am familiar with the linkage between aspartate/ligand binding, receptor methylation, and flagellar behavior re. style of locamotion, but I do not know what the bacterium does with the aspartate it ...
13
votes
1answer
649 views

When did CRISPR/Cas9 evolve and what is the likelihood that a superior system for live cell genome editing has already evolved on earth since then?

I've read that CRISPR/Cas9 is currently being implemented and tested for its ability to edit genomes in live cells, and that it is supplanting other genome editing tools in labs, such as TALENs and ...
2
votes
2answers
429 views

number of chromatids seen in karyotype

The karyotype is performed on a cell whose cycle has been stopped in metaphase or pro metaphase, using colchicine or by other means. In the textbooks I read that during the S phase each of the 46 ...
0
votes
1answer
47 views

Insertion Confirmation Cloning Strategy

So I am in a bit of a time constraint. Essentially, I inserted a DNA fragment via molecular cloning which contains a unique RE site. I need to confirm whether my colony has or does not have the ...
4
votes
2answers
102 views

How can you band wheat chromosomes using Giemsa dye?

I am working with wheat chromosomes and trying to stain the chromosomes. However, during staining with Giemsa dye chromosomes appear totally dark. I'm not sure why this might be. Anyone have any ideas?...
0
votes
1answer
22 views

What is ApoCas9 in the CRISPR-Cas9 system?

I am currently reading an article about a particular assay of Cas9 nucleases. In one of the experiments, they have used ApoCas9 (Apo variants of other CRISPR nucleases) as some sort of control. But ...
0
votes
0answers
44 views

plant uptake of large molecules

I have read several studies concluding that plants can indeed take up molecules with a molecular weight larger than 390 g/mol. Does this mean plants do also take up large molecules like hormones if ...
0
votes
1answer
46 views

Approximate Cell Doubling Time?

If I know it takes 12 min to occur in mitotic fibroblast cells and I count there are 32 dividing cells in the microscope slide out of a total population of 32034 cells, how do I calculate the ...
0
votes
1answer
41 views

Non-coding DNA as a protection to deleterious mutations

We know that most part of our genome (at least 75 percent) is non-coding DNA. Can it be a way to protect the organism from mutations in important genes, such as the ones which control cellular cycle, ...
3
votes
1answer
97 views

What Ultimately Controls DNA Transcription?

Transcription of DNA and further splicing of mRNA is regulated by various transcription factors, small nuclear RNAs and so on; similarly such related mechanisms as transposition of transposons. All ...
-2
votes
2answers
110 views

Why isn't the human zygote considered a human life how is a living anatomically modern human defined biologically? [closed]

It has 46 chromosomes by default when healthy(Differences almost always are pathological) and has almost every biological functions, processes a Newborn or and Adult person has. It even invades ...