Questions tagged [molecular-biology]

The study of the molecular processes underlying life.

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2
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1answer
96 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 ...
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1answer
204 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 ...
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2answers
42 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 ...
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1answer
90 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.
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0answers
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Allelic dominance and recessiveness [duplicate]

What is the reason for the allelic dominance and recessiveness of a gene? Is it all about the chance or probability of getting the fusion of a particular character ? So how can be there a dominance ...
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23 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
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1answer
644 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
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2answers
389 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 ...
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1answer
42 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 ...
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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?...
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30 views

Gene introduction in bacteria [closed]

I want to transform the bacteria with my gene of interest inserted inside a particular plasmid. However, transformation is not taking place due to bacterial exonuclease which is degrading the plasmid ...
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0answers
47 views

Can protein/codon chirality be described in tRNA molecules? [closed]

Is left-handed chiral protein and right-handed chiral RMS factored in to the tRNA molecuar structure? If so, how.
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1answer
18 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 ...
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43 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 ...
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5 views

Revert lettuce to vegetative phase by cutting it down [migrated]

I have read several article stating that it is possible to revert a bolted lettuce to vegetative grow by cutting it down to 1 centimeter. Is that right?
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1answer
44 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 ...
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1answer
35 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, ...
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0answers
21 views

Isolating enzymes participating in gluconeogenesis [closed]

Is it possible to isolate enzymes participating in the gluconeogenesis? An example would be to isolate fructose bisphosphatase and phosphoglucose isomerase. If yes, how do I do that without using very ...
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1answer
41 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?
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28 views

Is it possible for mitosis to occur in haploid (n) and triploid (3n) cells? [closed]

I understood that mitosis can occur in haploid cells and for many haploid cells it is the main process through which the cell can divide. However I'm unsure about triploid cells.
3
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1answer
90 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 ...
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2answers
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Why isn't the human zygote considered a human life how is a living anatomically modern human defined biologically?

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 ...
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20 views

How can I improve efficiency of Ecoli transformation?

I am an intern in biology institute. I have a 17.3kbp plasmid need to transform to Ecoli. But I have tried many time but have no or very few colony on LB plate. I know large plasmid have less ...
3
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1answer
48 views

Can denatured GFP show fluorescence?

GFP ( green fluorescent protein) can show green fluorescence. And its fluorescence is due to the tri peptide chromophore which is given in below I was wondering, can we observe fluorescence, if we ...
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0answers
24 views

How to troubleshoot in vitro formaldehyde fixation for nucleosomes?

For an experiment, I am trying to fix the mononucleosomes (100ng) using formaldehyde as crosslinking agent in HEPES buffer. I have been using 2% formaldehyde in a reaction buffer containing 1mM EDTA, ...
0
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1answer
29 views

Does anyone know a good pancreatic-cancer metastasis cell line?

Researching about pancreatic cancer. We have mostly "main-tumor" cell lines in our lab, and I´m currently looking for cell lines originating from metastases (liver, lung, etc.). Does anyone know a ...
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0answers
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Which animals don't have pheromones?

Which animals are known to not have pheromones besides humans? I can't find any research on this. There are examples of every class that uses pheromones. However nobody seems to answer conclusively ...
0
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1answer
30 views

Can Cas13 be used with multiple crRNAs in the same reaction?

CRISPR-Cas13 equipped with crRNA (complementary to transcripts of interest) can be designed to target ssRNA transcripts in cells. Upon successful crRNA and ssRNA binding, a fluorescent domain on ...
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1answer
31 views

How to do desalt reaction by passage through a Micro Bio-spin 6 column?

I want to perform the bisulfite sequencing on rRNA to detect the 5-mC. I followed this protocol • DNA-free™ DNA Removal Kit (Invitrogen) • Purified RNA, Treat RNA according to manufacturer's ...
6
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2answers
26k views

Why is the DNA helix anti-parallel? [duplicate]

Why is it that DNA strands are running in anti-parallel fashion? Given the chemical base-pairing, they could have been parallel just as well.
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1answer
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Difference Junk DNA and Pseudogenes [duplicate]

1-Are Pseudogenes and Junk DNA both Non-Coding DNA or they are different entity? How much Pseudogenes & Junk DNA do we have respectively? 2-I read that Non-Coding DNA has functions, my question ...
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15 views

Holder for 75 mm x 25 mm glass slides that can handle vibration

Hello Biology Stack Exchange, I have an application where I have cells on a glass slide (dimensions: standard 75 mm length x 25 mm width x 1 mm thick). I want to vibrate/shake the cells rapidly ...
2
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1answer
83 views

How to generate protein graphics for illustrating articles?

The structure of insulin shown below appears in a Wikipedia entry. What software was (or can be) used to create pictures of this type?
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3answers
30k views

Why are so few foods blue?

Although blue foods exist, they're rare enough compared to other foods for food preparers to use blue plasters as a convention. The natural colour of a given food is due to pigments that have some ...
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1answer
80 views

Does this article call into question the theory of evolution?

https://www.quantamagazine.org/neutral-theory-of-evolution-challenged-by-evidence-for-dna-selection-20181108/ The article above challenges how mutations work in evolution. Does this disprove the ...
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11 views

Why do people use J2 viruses for macrophage immortalization?

I've been trying to figure out how to go about immortalizing some primary alveolar macrophages harvested from mice. What I am seeing in the literature is that it seems like people have been using a ...
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2answers
63 views

What is the subcellular location of synthesis of non-essential amino-acids?

What is location of non-essential amino acids synthesis in a cell? Is it some specific organelle? And what is the gene driver behind this? I thought the whole point of DNA is coding for how to ...
1
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1answer
59 views

What is the role of CRISPR-dCas9 in gRNA-dCas9 transcription regulator complexes?

In this paper1, I read that mutant versions of Cas proteins such as a deactivated Cas9 (dCas9) are used alongside a guide-RNA (gRNA) to form variants of CRISPR tool that can function as transcription ...
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19 views

Biochemistry of pleasure of/desire for physical exercise in mammalians and humans?

Are there some known biochemical mechanisms, that induces desire for/pleasure of physical exercise in mammalians and humans? I have heard, that horses can not live without physical exercise and they ...
3
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1answer
29k views

Catabolic and Anabolic Reactions

How do we differenciate between catabolic and anabolic reactions? According to my researches; Catabolic Reactions Catabolic reactions (also called “catabolism”) break down larger, more complex ...
3
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1answer
35 views

What buffer should I choose for IEX chromatography for purifying IgY

I will use ion exchange chromatography with an anion exchange column to purify chicken IgY. Prior to this I did dialysis to remove salts from previous purification steps, is it possible after this ...
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0answers
17 views

Chemical inhibition of fertilization in plants

Are there any chemical compounds that inhibit fertilization in plants after gametogenesis? Simply put, I am talking about spermicide or emergency contraception for plants. Specifically, I am ...
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1answer
44 views

Application of molecular dynamics simulation (or alternatives) for the full pathways of protein interactions?

If one would like to control the biological system (e.g. to treat disease or aging/senescence) then one should introduce the drugs in the system, that initiate complex protein interaction pathways ...
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0answers
38 views

ATP and Muscle Contraction

I have a question regarding how molecular interactions manifest in physical actions - such as hanging from a bar. To the best of my understanding, when it comes to the contraction of muscles, ATP is ...
0
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1answer
29 views

Can I use a basic compound microscope to analyze the ploidy of plant chromosomes?

So, I'm not really any kind of trained botanist. But I do have two things: some dandelion seeds from France, and, collecting dust in my garage along with related accessories, this thing. Normally, ...
2
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2answers
168 views

What is the meaning of “Rb is in the active state”?

I am reading about cyclins, cdks and Rb (Retinoblastoma) and some of the terminology is not clear to me. I understand that when CDK phosphorylates Rb, it disconnects from E2F, and E2F can act as a ...
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0answers
25 views

How do receptors lose their sensitivity?

Recently, I learned that one of the causes of Type II diabetes is that insulin receptors on cell surfaces lose their sensitivity due to long-term high exposure to insulin (which occurs as a result of ...
3
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2answers
82 views

Does the lack of “mirror life” tell us anything about abiogenesis?

My (extremely rudimentary) understanding of Biology is that many of the building blocks of life are chiral and that life on earth is entirely made up molecules with the same chirality. Does this ...
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1answer
144 views

How are single-stranded binding proteins removed from the lagging strand during DNA replication?

The lagging strand, downstream of the Okazaki fragment, is covered in single-stranded binding proteins (SSBPs) during DNA replication. What is the mechanism which ensures that SSBPs are removed from ...
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What is the relationship between Ca- and Na-ions and mucins and why?

According to Wikipedia https://en.wikipedia.org/wiki/Mucin#Secretion mucins (Proteins that form mucus) obtain viscoelastic properties by the Exchange of sodium and Calcium Ions. What is Happening ...