2
votes
1answer
638 views

How to check if a fastq file has single or paired end reads

I am trying to check if a fastq file has single or paired end reads. How can I achieve this with an error-proof method? I checked wikipedia and MAQ but I want to know if is there a reliable document ...
7
votes
1answer
71 views

Are recessive, deleterious alleles less common on the X chromosome than the autosomes in humans?

As there is a potential for them to be more readily purged in hemizygous males (and in cell lineages in females with the deleterious-allele-bearing chromosome activated), I would expect the frequency ...
4
votes
2answers
95 views

Is there a standard reference for the importance of tumor heterogeneity?

In a recent post, Philip Gerlee highlighted the two biggest contributions of mathematical oncology to cancer research: (1) increasing focus on the progress of cancer as an evolutionary process, and ...
4
votes
1answer
90 views

What is the relation between plasmid concentration and mRNA levels?

Suppose a simple synthetic construct, consisting of a constitutive promoter and a single gene: One of the simplest ways to model GFP transcription is to use an ODE: $\frac{d [GFP_{mRNA}]}{dt} = a - ...
2
votes
0answers
181 views

MTT assay normalization

Since the precise amount of cells in each well of an MTT assay varies, how can I normalize the results by cell number/concentration? How can I take into account the number of cells that have already ...
9
votes
2answers
620 views

Gloves for Cell Culture?

I always wear gloves when I'm doing cell culture. Moreover, I always spray my gloves with ethanol to disinfect, so that I don't contaminate everything. However, I recently heard the argument that ...
1
vote
1answer
27 views

Distribution of genotypes after adverse selection

I am doing some research into Mendelian genetics and came across this phrase called adverse selection. I found a few questions but I am unsure of the calculations. ...
1
vote
1answer
69 views

Genotypic distribution of a population with two characteristics and linkage

I am currently doing some research into distributions and probabilities with Mendellian genetics. I came across this problem that I cannot seem to wrap my head around. Given that the population has ...
0
votes
1answer
90 views

What does this sentence about toxemia and Clostridium tetani mean?

I know that Cl tetani is not invasive and strictly localised. I think toxemia means spread in the blood. I am thinking this sentence The volume of infected tissue is small, and the disease is ...
1
vote
1answer
313 views

What are the pros and cons of eating earth (soil)?

I wonder if there are any benefits to eat earth. What I mean by earth is the topsoil that is sometimes on vegetable (I eat organic vegetables and some of them like spinach are full of topsoil). I ...
1
vote
3answers
87 views

Using PSI-BLAST

I understand that the first BLAST yields almost the same results as blastp. The second time the iterated blast generates different results as it uses different matrix based on our first result. But I ...
4
votes
1answer
224 views

Why is Homo sapiens not categorized as an invasive species?

According to Invasive Species Advisory Committee (ISAC), the definition of the invasive species is “a species that is non-native to the ecosystem under consideration and whose introduction causes or ...
2
votes
1answer
57 views

PCR enzyme units or concentration?

When performing PCRs, usually in every protocol enzyme amount is specified as 1.25 U as optimal per 50 uL reaction. Then, when running 25 uL PCR reaction should i use 1/2 he amount the enzyme or ...
2
votes
1answer
58 views

Pippin prep kits - expiration date

Do you use Pippin prep? We would like to buy it, but we need more info. What is the expiration date of kits for Pippin prep? Thanks!
3
votes
2answers
131 views

What are the physiological roles of Hydrogen sulfide?

I am thinking why hydrogen sulfide has its effects in the body. For instance, it is one Salmonella's virulence factor. I am not sure if such a balance equations holds H2O + H2S ←→ ... Actually, I ...
2
votes
1answer
152 views

Do bacteria with capsular antigen always have a capsule?

Assume some bacteria have capsular antigen. Do these bacteria always have a capsule? I think not, I think the antigen only makes it possible.
0
votes
1answer
63 views

How can eating bacon not make me fat? [closed]

This page says it won't. This page says it's the carb again http://www.mindbodygreen.com/0-10454/in-defense-of-bacon-why-eating-fat-can-help-you-get-thin.html I don't see how eating fat will not ...
1
vote
1answer
158 views

Why will world population keep growing if all women have only 2.1 children

Why is it that, even if we were going to immediately agree that every women will not have more than 2.1 children on average, the world population would continue to grow for another 60 years? I've ...
0
votes
1answer
70 views

Hidden Markov Model

I read about the hidden markov model in bioinformatics. I amn't able to understand what it is. Can anyone explain me in brief and in very very simple words what it is ? I have NO background in ...
1
vote
0answers
45 views

Nearly Exhaustive List for Cholesterol Pathways [closed]

I have run across an interesting case that is similar to only two others I've encountered. What makes it interesting is the combination of undetectable (under normal testing conditions, can elaborate ...
1
vote
1answer
59 views

What are the purposes of granulocytes in acute inflammation?

I heard the phrase Neutrophilic leucocytes are kings in the acute inflammation. Neutrophils are granulocytes, while leucocytes are not granulocytes. I think this statement refers to the fact ...
6
votes
1answer
82 views

Visualisation of phylogeography

I am working on phylogeography on one model species and I am a beginner. You can imagine one species that came on locality more than 5 mya (million years ago). It was a good environment, so the ...
1
vote
1answer
238 views

What are some of the known fungi with heat resistant spores

Are there any fungi whose spores can survive 100+ degrees for 15 minutes and grow in a sugar-deprived medium?
1
vote
1answer
95 views

Giardia lamblia cases of infections

I am wondering if anyone has seen a data of Giardiasis (Giardia Lamblia) cases in different countries on the world? I have found for different diseases and also for 'diarrhoea diseases' in general, ...
2
votes
3answers
87 views

Quantitative Differences : DNA and Gene

After HGP, we are not having many databases which consist of several notepad files of ATCG.... Can we distinguish quantitatively a given A,T,C and G stretch as DNA or Gene?
6
votes
1answer
81 views

How can one accurately diagnose the cause of human hearing loss without surgery?

In a human, if you were to avoid a tympanotomy (surgical examination of the middle ear), how could you distinguish between a blocked Eustachian tube, a ruptured eardrum, or a perilymph fistula? For ...
9
votes
1answer
149 views

Circular mRNA to produce long proteins

Ribosomes can read mRNA and produce proteins, if we somehow make a circular mRNA for the ribosome to bind onto, it will make infinitely long "proteins", (since ribosomes can make very big proteins, I ...
3
votes
1answer
385 views

What are the highest and lowest possible pH, paCO2 and HCO3 in the blood of living human?

What are the highest and lowest possible values of pH, $paCO_2$, and $HCO_3$ in the (arterial or venous) blood of a living human being?
2
votes
1answer
117 views

eye myopia power changes with brightness

Is there a condition where myopic power changes with ambient brightness. When I drive in the morning in bright sunlight my power is -4.0; however when I wear the same -4.0 glass in the evening (dusk ...
2
votes
2answers
84 views

What's the point of glycolysis in fermentation?

In order to get glycolysis started, you need 2 ATP. In the process, you can generate 4 ATP. That results in a net gain of 2 ATP. Hooray! But wait. If you don't undergo glycolysis, then you've got an ...
3
votes
2answers
303 views

Can Listeria monocytogenes endotoxin act as an A-B toxin?

I think no, but I am not sure since Listeria is Gram-positive and probably has lipopolysaccharide (exception among Gram positive bacteria). Can Listeria monocytogenes' endotoxin act like exotoxin ...
9
votes
2answers
498 views

How are viruses weakened to be suitable for vaccination?

I understand there are two kinds of active vaccination Injecting complete viruses that are weakened to not cause the disease being vaccinated against Injecting only antigen particles of viruses that ...
1
vote
1answer
406 views

All flowering plants gives fruits. Why does jasmine flower plant not yield fruits?

My question is actually my long term doubt. I have seen most of the flowers turning into fruits. But why not this jasmine flower?
1
vote
1answer
84 views

parallels or replicates?

I am writing an article where I describe real-time PCR experiments. My collaborator, after reviewing the article, consistently replaced the word "parallels" with "replicates". Are they not synonymous? ...
5
votes
1answer
1k views

How to avoid air bubbles while pipetting?

I get air bubbles while pipetting small volumes. How can I avoid them ?
2
votes
3answers
168 views

Evolution (Reductionism)

My recent post was tagged as unclear so I wanted to re frame my question. Though I am a layman, I would love to read books and find the stuff, if I get an overall picture of intelligence factor. My ...
2
votes
2answers
386 views

Promoter in the lac operon

Here is the question: Suppose an experimenter becomes proficient with a technique that allows her to move DNA sequences within a prokaryotic genome. If she moves the promoter for the lac operon to ...
1
vote
1answer
122 views

Genetics independent assortment?

As indicated in this question, what do you think is is the best explanation for the observed progeny, is it because distance between genes affects recombination frequency? My main concern is ...
0
votes
1answer
537 views

What is the significance of and biological mechanisms demonstrated in lac operon?

I would appreciate it someone could explain clearly how the genes in the lac operon of E coli are activated to allow the bacteria to metabolize lactose? The part that I really don't understand is ...
2
votes
1answer
73 views

What is the creature with the lowest neuron count that demonstrates cognition beyond reflexes?

I'm under the impression that nematode worms just perform the same scripted actions over and over again in response to specific stimuli. They have 302 neurons. Chimpanzees display problem solving ...
1
vote
1answer
55 views

how cells make other macro molecules?

We know that the nucleus of the cell is the White House of the cell and its DNA is the president and it commands to make protein. So my question when DNA only codes for protein and enzymes,after the ...
-3
votes
1answer
91 views

Can cancer be an immune system disorder? [closed]

Can cancer result from a weakened immune system? Would this mean that cancer could be considered an immune system disorder?
0
votes
1answer
83 views

Length differences between physically interacting proteins

What can be said on the length differences between interacting proteins? Are they usually of similar sequence lengths or not at all?
1
vote
1answer
91 views

What cell types produce immunoglobins and where are those cells found?

I know B cells found in bone marrow produce immunoglobin G. But IgM is produced in mucosal cells at least in the gut. Can you find immunoglobin expressing cells in other tissues in the human body? ...
-3
votes
1answer
79 views

Biopython error [closed]

...
7
votes
2answers
296 views

What causes skewed lanes in a DNA gel electrophoresis experiment?

In gel electrophoresis, what causes effects like these (see collumn 11 in the first one, an collumn 6 in the second). ? (These images were samples that I took from an online activity we did for ...
7
votes
1answer
76 views

Gap junction turnover

Gap junction proteins, connexins, are known to form intercellular hemichannels, between two adjacent cells. These junctions are maintained cell adhesion proteins (cadherins), yet the turnover of ...
5
votes
2answers
3k views

How do we know that everybody's DNA fingerprint is unique?

How do we know that everybody's DNA fingerprint is unique? I know, I know, everybody's DNA is unique. But when we do DNA fingerprinting, we're looking at very specific regions of high variability. ...
1
vote
1answer
707 views

What's the difference between an embryo and a fetus?

The most I've been able to come up with is that fetuses are embryos slightly farther along in their development. Is that correct? Thanks! evamvid
6
votes
1answer
239 views

How can promoter binding sites be determined?

I have been trying to find out which sigma factor is responsible for the transcription of RNA polymerase subunits $\alpha$ (rpoA) and $\beta ^{\prime}$ (rpoC) in Bacillus subtilis. I would expect it ...

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