Questions tagged [molecular-biology]
The study of the molecular processes underlying life.
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Which molecule that an excess of inhibits B-oxidation?
Which molecule that an excess of inhibits B-oxidation?
a. Acetyl-coA
b. Malonyl-coA
This question is so debatable, because both are correct
However, according to my professor, only one is ...
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14 views
Antigen molecular mimicry
Let us consider a situation in which the body is attacked by a microbe, and the microbe is captured by the immune system for recognition of surface antigens.
The surface antigen recognized mimics one ...
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1answer
29 views
Is studying chemical and physical properties of chemical substances that make up organisms really a task of molecular biology?
I have read in a high school textbook that (translated into English by myself): "Branch of science that concerns itself with studying chemical and physical properties of substances that make up ...
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How efficient is direct cloning in budding yeast?
I am trying to make a clone using E.coli as host and use that clone later to transform budding yeast. But, I am not able to get clone somehow so I was wondering to perform lithium acetate ...
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What chapters from the Campbell Biology 11th edition textbook are covered in the AP Biology curriculum/exam? [closed]
I am currently taking College Biology in high school but I plan to take the AP exam in May. The syllabus for my class skips a lot of the chapters in the Campbell Biology textbook. I would like to know ...
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1answer
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What is the difference between a signal peptide and a transit peptide?
From what I know, the two names are used interchangeably and I haven't found any resource which says otherwise either. Is there at all any difference, is there a transit peptide that is not a signal ...
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Can we spike with a different enzyme to a SYBR Green Master Mix?
I followed the standard SYBR Green Protocol for doing a qPCR. For which I used
10 uL of 1X SYBR Green Master Mix
Forward Primer and Reverse Primer (each at a final conc. = 8.5 uM)
Template (unknown ...
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31 views
Reproduction - can we say that the rejuvenation is not miracle and the Nature is doing it constantly? [closed]
I am big fan of rejuvenation and indefinite life extension - there are good research along these lines, e.g. http://www.sens.org/research/introduction-to-sens-research/extracellular-junk (the best, ...
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1answer
34 views
Barr body. How does it work?
Barr's body is a spiral X chromosome. If I'm not mistaken, one random chromosome (a healthy woman) is inactivated in each cell. Which X chromosome is inactivated in a given cell is random. I've heard ...
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1answer
43 views
Why is Turner's syndrome a problem?
So Turner's syndrome is a chromosomal defect where one of the X chromosomes is missing. For more details visit the [Wikipedia page]
(https://en.m.wikipedia.org/wiki/Turner_syndrome).
But I don't ...
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1answer
19 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 ...
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1answer
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Why don't the heads of phospholipid bilayers repel hydrophobic molecules?
What I Think I Know: Hydrophilic and hydrophobic things repel each other. Since the cell membrane contains hydrophobic tails, it is difficult for hydrophilic molecules to pass through the cell ...
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1answer
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What would “N” and “V” stand for in DNA barcoding?
I'm currently looking protocol for PAT-seq, and when it talks about the barcoding that's utilized, the documentation mentions there being an "N" and "NN" in the sequence, as well as a "V". For example:...
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2answers
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Are redundant codons used in translation?
I am learning about redundancy in genetics and I came across this statement in my textbook:
more than one codon for an amino acid means that some codons are redundant - the process of protein ...
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0answers
22 views
(Reliable Source Needed): Why is the phospholipid membrane more permeable to hydrophobic molecules?
It is often said that it is difficult for hydrophilic molecules to pass through the phospholipid bilayer because of the hydrophobic core. However, it would seem logical to assume that it would also be ...
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1answer
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Will DNA nanostructures be useful for medical applications?
There is a lot of work being done on developing small nanomechanical structures and even small nanomechanical actuators built with DNA. I have heard researchers motivate this research with claims ...
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How does Ran GDP get from the cytoplasm back to the nucleus following nuclear import and export?
I understand that in Ran-dependent nuclear import Ran GTP binds importin in the nucleus, and after diffusing through the nuclear pore complex Ran GTP is hydrolyzed to Ran GDP and releases importin. ...
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1answer
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What is trans-complementation?
Is trans-complementation a complementation of transgenes?
The crystal structure reveals a trans-complementation mechanism whereby an incomplete immunoglobulin-like domain assimilates an isoform-...
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4answers
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What is the longest-lasting protein in a human body?
Protein life times are, on average, not particularly long, on a human life timescale.
I was wondering, how old is the oldest protein in a human body? Just to clarify, I mean in terms of seconds/...
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1answer
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Why are there inverted repeats in response elements?
The following picture shows an inverted repeat sequence in a response element. Response element sequences for glucocorticoids, estrogen, and thyroid hormone show that they all contain inverse repeats. ...
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1answer
19 views
Hydrophobic interactions in the helix-turn-helix
This slide states that the second helix works to stablize the configuration of the two helixes via hydrophobic interactions. What exactly is this hydrophobic interaction? In other words, what ...
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7 views
Cell wall constitution of Schizosaccharomyces pombe
where is located the 1,3-α-glucan in the cell wall of Schizosaccharomyces pombe?
Is it in the inner or outer layer?
Thanks
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1answer
53 views
Protein electrophoresis
Three proteins A, B and C of equal molecular weight are being investigated in a study. They contain six, four and four cysteine residues respectively. Only Proteins A and B were treated with β-...
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2answers
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Name of dsRNA (or dsDNA) where all strands are identical
What is the name of dsRNA (or DNA) where all component strands are identical (i.e. where the complex consists of multiple copies of the same ssRNA)?
Example: 2 identical ssRNAs forming a dsRNA
...
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0answers
29 views
Does every protein encoding gene necessarily have a transcription factor?
For instance, transcription factor gene A is responsible for activating gene B that encodes protein 1.
However, it is possible for genes like gene B to encode proteins without having transcription ...
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2answers
150 views
What makes/breaks the hydrogen bonds between DNA and RNA during transcription?
So I know that RNA polymerase catalyzes the phosphodiester bonds that hold the sugar backbones of a growing mRNA molecule together during transcription. However, I'm less sure about the hydrogen bonds ...
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What's the difference between beta thalassemia minor and beta thalassemia intermediate?
I mean beta thalassemia minor is caused by inserting one abnormal allele while beta thalassemia intermediate is when the person has at least one B+ allele. Is beta thalassemia intermedia a type of ...
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Questions to protein folding
I have some questions regarding the process of Protein folding. These are the following:
Are there existing Protein folding processes, where only a few seconds after completed folding a Protein ...
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1answer
59 views
Does the deletion of Chromosome 20 cause immunity against prion disease?
I was reading recently about prion disease and it caught my attention that a normal prion protein is coded n chromosome 20, therefore, in order for an infectious prion protein to attack, there must be ...
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1answer
31 views
What does it mean to use DMSO as a dissolvant in biology experiemnts?
In many biology publications, I saw that dimethyl sulfoxide (DMSO) is used to dissolve drugs. However, the cell-based assays are still performed in water-based medium such as RPMI or PBS.
My ...
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3answers
79 views
You need DNA to make RNA, and RNA to make DNA, so they had to come into existence at the same time?
A statement I recently read: 'Evolution is debunked and gives no basis for morality. Natural Selection throws away info, it does not add.
You need DNA to make RNA, and RNA to make DNA, so they had to ...
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1answer
39 views
How to find idea for essay [closed]
I'm studying microbiology in Iran
The university that I'm studying in doesn't provide that much help in research areas and we don't get to research or write essays that much ,while I'm trying to write ...
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Fruiting of trees — environmental stimuli and biochemical cascades
My question concerns fruiting of trees in general. However, I live in a
tropical country (Philippines) where mango trees are ubiquitous, so I'll use it
in stating my question.
The question is about >...
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How the albumin regulates osmotic pressure
Do I understand correctly that:
When albumin binds non-water molecules to itself, the concentration of non-water molecules decreases, thus the osmotic pressure decreases;
When albumin carries water, ...
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0answers
54 views
Why does M1 RNA together with C5 protein in 100mM Mg(II) fail to cleave tRNA?
Sidney Altman discovered that RNA moeity of RNAse P (M1 RNA) alone is able to perform enzymatic cleavage of ptRNA, which won him the Nobel Prize of Chemistry in 1989.
However, when I read the Nobel ...
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2answers
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Chemistry of phosphodiester bond formation by DNA polymerase
As I'm teaching General Biology to my college students, I realized that I don't fully understand how a 3-P nucleotide like ATP is broken down to be incorporated into DNA during replication. How does ...
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1answer
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Is one STR be enough for a reliable identification in real life?
The lab simulates the analysis of just one STR in the genome. Would this analysis be sufficient for a reliable identification in real life? If not, explain what could be done using DNA to identify ...
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How do Introns in pre-mRNA interrupt gene transcription?
This is stated as obvious in one of my textbooks. Can anyone explain how this works ? How does a product of transcription interrupt transcription ?
Picture to demonstrate.
Legend:
E: Exon
...
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1answer
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Biology and dna samples to determine parental lineage [closed]
How could you use nuclear and mitochondrial DNA samples run through electrophoresis to determine parental lineage.
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1answer
36 views
How is the timing of gene expression controlled in developing embryo? [closed]
I understand how cell differentiation works in general (gradients of homeobox proteins etc), but how is timing controlled? Why do some genes switch on at a very specific moment of development and then ...
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23 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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What conclusions can I draw about the size, charge, and shape of messenger molecules?
Molecules such as cAMP or Inositol trisphosphate are used in organisms as messenger molecules that make things happen when they are supposed to happen. These molecules are usually big, but not too big,...
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What do halophiles eat?
We all know that halophiles can survive salt environments and all that, but what do they really eat? Do they consume the salt in their habitat?
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Why did scientists think humans had 100,000 genes (before the Human Genome Project)?
One of the major results of the Human Genome Project (HGP) was that humans have far fewer separate genes than previously thought. From a 2004 article about the HGP:
Francis S. Collins, director of ...
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Is there a good source for detailed molecular/atomic information about plant cells?
Can anyone point me to a good source for understanding the molecular/atomic details for the structure of a plant cell?
For each element of the plant cell, I want to know what kinds of molecules/atoms ...
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1answer
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identification of differentially expressed genes in RNA-seq analysis
I am using four different packages (viz. EBSeq, DESeq2, edgeR, LPEseq) for identification of differential genes. Now I am confused whose fold change value should I take for further downstream ...
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2answers
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How do I calulcate the amount of concentrated stock solution to add to get the correct dilution?
For example, how much loading buffer (6X) do I need for my PCR reaction with a volume of 25 μl? What is the general way to calculate it?
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How can two biological sequences be anything but homologous?
If we consider homology between two nucleotide sequences as a yes/no answer to whether they have shared a common ancestral sequence, then given that all life share common ancestry and sequences are ...
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Meting temperature of PCR products and product expected size
I know the Melting temperature of my primers but I would like to know if the melting temperature of my product match with the melting temperature I get in the melting curve when doing a qPCR, in order ...
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What does “novel, predicted deleterious, within autozygome” mean in genetics?
I am a medical student and just got involved with a genetic lab and research. I read a lot phrases like: "Although no mutations have been reported in this gene, we think this variant is interesting ...
