3
votes
1answer
3k views

Why is beta-mercaptoethanol often added to cell culture media

Many protocols suggest that beta-mercaptoethanol is necessary for growing cells. It is a reducing agent but what does it mechanistically do for your cells. When would one not add it.
5
votes
1answer
136 views

Does every gland type have stem cells for regeneration?

Is there any gland in which there are no stem cells? I know that: sebaceous gland is maintained by unipotent stem cells thyroid gland - some stem cells, apparently unipotent Glands about which ...
3
votes
2answers
3k views

How do you calculate or predict the charge of a protein at pH 7?

How do you calculate or predict the charge of a protein at pH 7 given a fasta sequence? Any papers or online servers to do this is well appreciated.
4
votes
2answers
156 views

What is the purpose of the adrenal medulla?

The adrenal medulla is less of a 'real' endocrine organ like the others in the endocrine system and much more an extension of the sympathetic nervous system. In fact, its chromaffin cells are modified ...
2
votes
1answer
56 views

What is an efficient way to spike 10-50 cells to a culture

I'm trying to add on the order of 10-50 mammalian cells to a mixture of other cells (order of 1e6 cells). What is the best way to do this? (edit) I guess this wasn't clear. I would really like to ...
10
votes
4answers
7k views

Do we get 1/4 of our genes from each grandparent?

I know that we get half of our genes from each parent, but does it necessarily mean we get 1/4 of our genes from each grandparent? Or is it possible that we might get say 30% from one grandparent, 20% ...
3
votes
1answer
747 views

What happens when cells in your body run out of telomeres?

In my biology book I read about an experiment where the genes encoding telomerase were 'knocked out', but they could still live a normal life and no adverse effects were noticed until the 6th ...
5
votes
1answer
121 views

Is extreme cladism a mainstream position in the species debate?

In the philosophy of biology it has been claimed many times that a popular position regarding the question of what species are, among biologists, is cladism. For my current purposes, the defining ...
6
votes
1answer
88 views

DNA methylation and genome size

Is there any relationship between DNA methylation as a level of stability to epigenetic states and genome size? For example, it is claimed that DNA methylation is not required for epigenetic stability ...
3
votes
1answer
476 views

Is collagen supplementation useless?

When collagen is digested is it broken up into usable components that the body can use to produce its own collagen? What evidence is there that supplementing with collagen type I & II etc.. can ...
4
votes
1answer
66 views

Features in individuals causing high population variation

As I understand it, a population with high variation is something sought after, since it makes the population better equipped to face a dynamic environment. Then, I guess features in an individual ...
7
votes
1answer
106 views

Do any plants exhibit hormonal changes similar to puberty?

Just what the title states. Are there any plants/trees that exhibit a growth spurt at a definite interval after the shoot appears?
7
votes
2answers
131 views

Genetic Models for Natural Selection?

My question is simple: Given that evolution is described by random genetic mutations allowing certain members of a species to gain a reproductive advantage over others that coexist in the particular ...
11
votes
1answer
277 views

Do single crossovers occur in circular polynucleotides?

Single crossovers in circular pieces of DNA do not seem to be a big topic, because if they happened, they would lead to a kind of combined chromosome with two inner strands and one large outer strand. ...
5
votes
1answer
2k views

What are tendons made of specifically

From what I read on wikipedia they are made of collagen. Collagen is just a protein. Right? How is this collagen structured (I imagine like fibers). Aren't there cells in this fibers as well? From ...
3
votes
0answers
246 views

What is the timing of information assimilation within a human brain? [closed]

A little background: I'm an avid dreamer and have great dream recall, sometimes up to 5-7 per night. In my experience, I can sometimes trace some elements of the dream to an event that occured ...
3
votes
1answer
428 views

Could inhibition of progerin formation slow the rate at which a body ages?

According to wikipedia, progerin is activated in senescent cells. The protein itself is known to be the cause of a rare affliction 'progeria' - a disease marked by accelerated aging of the body. This ...
9
votes
1answer
83 views

Relative Property of Alleles

If there are three different alleles to a gene, is it possible that the first is dominant to the second, but recessive to the third?
3
votes
1answer
555 views

Open protocol for Ligase Independent Cloning

Ligase Independent Cloning is a protocol that allow an insert to be integrated into a vector without ligation. It uses T4 DNA polymerase with only ATP to first chew back from blunt ends to create ...
8
votes
2answers
193 views

Is there a consensus on whether or not race exists on a biological level?

The most recent survey I could find was from 1985 which said that 16% of biologist disagreed that "[t]here are biological races in the species Homo sapiens." I was wondering if there's been a change ...
11
votes
1answer
278 views

Deletion errors with Phusion Polymerase?

I was wondering if anyone has ever seen large deletions (~40-50 bp) occur when using phusion polymerase to clone a gene. I have recently tried using Circular Polymerase Extension cloning to clone a ...
6
votes
2answers
9k views

How do archaea relate to eukaryotes and bacteria?

I've read that they all share some genes, internal structure, and behaviour with each other, but with different degrees of overlap depending of what the function is. E.g., archaea have some eukaryotic ...
4
votes
1answer
96 views

Online toolkit that provides functional similarity scores (in the form of a matrix) between two functional gene sets in the context of gene ontology

Where can I find an online toolkit that provides functional similarity scores (in the form of a matrix) between two functional gene sets in the context of gene ontology? I have tried the following: ...
6
votes
1answer
144 views

Alternatives to fittest-win and Moran processes as simple mathematical models of selection

When modeling selective sweeps as a micro-building block in models of macroevolution (not to be confused with misuses of this in creationist arguments), I use the fittest-win model of selection as a ...
6
votes
1answer
236 views

What is the relative power of GWAS studies in different species?

I would like to know of any publication studying the relative power of GWAS studies in different species. For example, I've seen reports that say genotyping and GWAS in dog breeds is much more ...
3
votes
1answer
189 views

What is the DNA/protein charge ratio?

To study DNA-protein interaction, I want to do a DNA retardation test by mixing the protein with DNA and afterwarts loading it on an agarose gel to see if the DNA migrates slower. I've found some ...
3
votes
1answer
4k views

What does the term 'bioavailability' mean?

From what I've read, Bioavailability is the degree to which food nutrients are available for absorption and utilization in the body. How would you explain this with an example?
6
votes
1answer
315 views

Can I estimate leaf temperature from air temperature? What other information would be required?

Physiological measurements such as respiration rate and assimilation rate depend on temperature. Most papers report tissue temperature (e.g. leaf temperature for leaf measurements), although some ...
1
vote
1answer
34 views

Where can I find a transcriptome of a normal uveal melanocyte?

I am looking for a database where I could find a transcriptome (say obtained with a microarray analysis) of one (or ideally many) normal uveal melanocytes ?
1
vote
1answer
73 views

TFBS predictions for yeast and pombe?

Are there any resources out there for TFBS (transcription factor binding site) predictions for the yeast (S. cerevisiae) and S. pombe genomes? Even if these are only de novo predictions, I would like ...
1
vote
2answers
291 views

How are proteins formed?

Somewhere, I have read that we need to consume proteins to make amino acids to make new proteins. What does it suggest? How do we make proteins from proteins?
6
votes
1answer
125 views

Designing genes with DNAWorks: Maximum nonzero score?

I'm designing a gene in DNAWorks, and I'm unable to find a set of conditions that gives an "overall score" of zero (which is what I normally insist on). People that have used DNAWorks: what's the ...
10
votes
1answer
269 views

How old does a baby have to be before it can retain memories?

For most people (my earliest memories are of perhaps when I was 2 or so) their earliest memories would be when they were over a year old. How old does the average baby have to be before it can ...
7
votes
2answers
281 views

Why do people have darker skin in sunnier climates?

I don't understand why darker skin is advantageous in hotter climates. Wouldn't it absorb more of the heat? I have heard that it reduces the incidence of cancer, but I would think absorbing more ...
6
votes
1answer
148 views

Are there any DNA base sequences that are fully conserved between the genomes of all humans?

That is, they don't differ throughout the entire population. I understand of course that we can't DNA sequence every human, so by "fully" I mean there's an incredibly small probability of there being ...
7
votes
2answers
5k views

What are the consequences of voluntary total celibacy?

Psychologically this might be a tough question, but in means of biology, what are the effects of total celibacy on the gonads and the nervous system concerning both man and woman in short and long ...
2
votes
1answer
77 views

Are there any organisms with larva more advanced than adult form?

Usually adult organisms are more sophisticated than corresponding larva, i. e. frogs, mosquitoes, fish. Are there species where the opposite is true?
14
votes
5answers
665 views

Pipetting damage on cells

I'm curious how much damage is potentially inflicted by shear stress by pipetting. I know that with syringes for stem cell injection cause a lot of damage. However, to what extend does this happen ...
3
votes
1answer
1k views

What are the units of Q10 (temperature sensitivity)?

Q10 is the increase in a rate (e.g. activity of an enzyme) observed with a 10 degree temperature increase. According to Wikipedia: It is apparent that the units of R (e.g. mol/g/s) cancel out, ...
1
vote
0answers
57 views

bam viewer that works on authenticated ftp urls with username/password combination? [closed]

Are there any BAM file viewers that will work on authenticated ftp urls with username/password combination? For example, something like this: ...
4
votes
2answers
81 views

How do proteins and genes participate in learning?

I am a computer scientist that studies biology and bioinformatics. In the last weeks, I have been trying to study new research directions, and I would like to deepen my knowledge on the role and ...
8
votes
1answer
347 views

Is sexual reproduction outside the same biological family possible? Has it ever occured successfully?

Are there any examples of two species taxonomically classified in different biological families that have successfully hybridized and produced viable offspring? If not, is there an example of where ...
6
votes
2answers
596 views

Finding the number of chromosomes of an organism

For a school project I need to find the number of chromosomes of an organism (specifically the adelie penguin, Pygoscelis adeliae). After several internet searches and a look through the encyclopedia ...
1
vote
1answer
975 views

Is there a free alternative to Gelcompar for comparing banding patterns across multiple gels?

In order to run my microbial community samples from my experiments through DGGE, I was required to use multiple gels. Thus it is necessary to compare banding patterns across more than one gel. ...
5
votes
1answer
117 views

Significance of basal lamina for outer layers of epithelium

In stratified (not pseudostratified) epithelia such as the epidermis, what purpose does the basal lamina serve for the outer layer cells which do not even stand in contact with it? Also, how do these ...
-3
votes
1answer
701 views

How does protein help to cure wound? [closed]

I understand that the protein helps to repair body tissues. If I increase the intake of protein, would it help to cure the wound more quickly? I would like to know how does the protein reaches the ...
5
votes
1answer
144 views

Homologies to insect wings

All winged vertebrates have wings which are homologous to each other and to the forelimbs of the non-winged vertebrates. But what about insect wings? Are all insect wings homologous, and are there any ...
7
votes
5answers
341 views

Introductory literature for synthetic / systems biology?

I'm a computer engineer (MsC Computer Engineering) who's looking to switch into the field of synthetic / systems biology. I've got a comprehensive layman's understanding of evolution, genetics, ...
0
votes
1answer
269 views

Why does a drop of water penetrate deep sleep? [closed]

Sleeping under the stars, a breeze carrying a few drops of water came by. The sense of water drops on my arms woke me up. I'm curious Why does the sense of a drop of water on one's body penetrate ...
12
votes
4answers
520 views

Why did high A+T content create problems for the Plasmodium falciparum genome project?

The main paper for the Plasmodium palciparum genome project (Gardner et al., 2002) repeatedly mentioned that the unusually high A+T content (~80%) of the genome caused problems. For example they imply ...

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