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.
4
votes
1answer
65 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 ...
23
votes
4answers
990 views

Why do men have nipples?

I'd be tempted to call nipples in men vestigial, but that suggests they have no modern function. They do have a function, of course, but only in women. So why do men (and all male mammals) have them? ...
10
votes
3answers
545 views

What is the most heat-tolerant organism?

What is the most heat-tolerant (or heat loving - hyperthermophile) organism so far identified? What adaptations does this organism have in order to endure such high temperatures?
4
votes
1answer
129 views

Regarding TIMP and MMP enzymes

Are there substances that can promote TIMP enzyme production, or MMP enzyme production or supression in tendons? Are there medical tests that measure quantities of MMP and TIMP enzymes in tendons?
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 ...
6
votes
1answer
82 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 ...
6
votes
2answers
73 views

Macrophage pathogen fixation

Overly simplified, macrophages recognise pathogenic patterns and endocytose anything that matches them. That also works on bacteria, which are quite often very mobile. What if a bacterium was just ...
6
votes
1answer
252 views

Which organisms have the neuroanatomy Roger Penrose supposes play a role in consciousness?

In The Road to Reality, Roger Penrose suggests that certain brain structures might play a role in consciousness Most particularly, lattice neuronal microtubules, as originally suggested by ...
9
votes
1answer
76 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?
7
votes
2answers
439 views

How do we know the brain flips images projected on the retina back around?

Why do we turn images upside down again rather than dealing with them directly, still vertically rotated after passing through our lens? I don't see how that would cause any problems, and how we'd ...
9
votes
1answer
763 views

Why do we like salt?

A few friends of mine told me that salt provides zero nutritional value to us, and in fact can harm our bodies. Now, these guys are medical students, and being an engineering student myself, I decided ...
3
votes
0answers
217 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 ...
5
votes
3answers
492 views

When to measure resting heart rate and blood pressure for following day-to-day trend?

I'd like monitor my resting heart rate and blood pressure to see how they are affected by regular cardiovascular training and other events in life. When should I take the measurements in order to ...
13
votes
2answers
573 views

Does testosterone increase female sexual behavior?

According to my lecture notes testosterone generally increases sexual behavior. Given that it's generally thought to be the male hormone I'm not quite sure whether they mean that it also increases ...
3
votes
1answer
169 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 ...
8
votes
2answers
170 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 ...
17
votes
4answers
992 views

How do trees manage to grow equally in all directions?

I was walking down a road with these beautifully huge trees when this question occurred to me. Large trees with many thick branches have to grow equally in all directions, or they would tip over. Is ...
2
votes
1answer
72 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?
6
votes
1answer
219 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 ...
20
votes
3answers
1k views

Is it necessary to conduct a power analysis before beginning an experiment?

I know that power analysis is the statistically valid way to ensure you use the correct numer of samples or repeats in an experiment. But I have never seen any biologist actually conduct a power ...
7
votes
2answers
4k 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 ...
6
votes
1answer
119 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 ...
3
votes
1answer
3k 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?
1
vote
1answer
33 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
68 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 ...
10
votes
1answer
243 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 ...
6
votes
2answers
109 views

phylogenetic analysis of gene enrichment?

Are there any tools to do phylogenetic analysis of gene enrichment? This is, I have a list of genes from an experiment performed in several species, with a z-score that can be described as ...
6
votes
1answer
132 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 ...
4
votes
2answers
484 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 ...
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 ...
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
56 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: ...
7
votes
1answer
202 views

Compare and contrast “Rubisco activity” and “assimilation rate” (is there a difference, and if so, what is it)?

I am confused about the variable "RuBisCO activity". How is it measured, and is it any different from the net assimilation rate? Based on some background reading (e.g. Kling, 2008; Lambers et al ...
6
votes
1answer
346 views

Is it purely the nervous system causing vaginal lubrication (arousal)?

My girlfriend was watching some documentary on TLC about a paralyzed woman getting pregnant. I believe that woman still has some feeling, as she spoke about feeling the effects of a bladder ...
3
votes
1answer
280 views

What are samples of “Outlaw Genes”

I read this in a paper Keller and Ross describe their greenbeard gene as an ‘outlaw’. Admittedly, the comment is only made in passing, but are they correct? In this context an outlaw is ...
5
votes
1answer
130 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 ...
-3
votes
1answer
604 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 ...
1
vote
0answers
53 views

Are the intestinal flora substantially different within a diverticulum of the colon?

From the Wikipedia page for the vermiform appendix: This proposal is based on a new understanding of how the immune system supports the growth of beneficial intestinal bacteria, in combination ...
-2
votes
1answer
162 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 ...
4
votes
1answer
450 views

Auxotrophic complementation test with yeast

If auxotrophic strains grow on minimal media do they complement each other or not? Also, is complementation the same thing as complementing each other?
3
votes
2answers
122 views

How distantly related are eusocial insects? Aren't members of a species much more related than 1/4, 1/2, or 3/4? [duplicate]

Possible Duplicate: How many genes do we share with our mother? I went to a lecture that talked about the behavior of social insects in terms of their relatedness of genes. For instance, ...
2
votes
1answer
95 views

What are Haplogroups?

What exactly does the term Haplogroup or Haplotype means? How is it claimed that people belonging to the same haplogroups have common ancestors?
5
votes
1answer
580 views

How and why did mouth and nasal cavity evolve separate?

My initial objection is that nose filters air, mouth is for eating but is used for breathing also, plus they both are used to create sounds. What is the cause and reason in this case, why do we need ...
2
votes
0answers
142 views

Too few transcripts from transcriptome assembler Oases

I am trying to run Oases for transcriptome assembly. The result is far from expected, so I would like to ask whether I am running it in a right way? Thanks. Here is my running command: ...
2
votes
1answer
613 views

What is the reaction mechanism of dopamine hydroxylase converting dopamine to norepinephrine?

The reaction is basically shown below. Dopamine hydroxylase is an enzyme, so I'm not sure if we can have a theory based on organic chemistry. On the other hand, maybe there is a theory that involves ...
7
votes
2answers
102 views

Does the word “polymorphism” refer to the gene, the phenotype, or both?

In genetics, does the word "polymorphism" properly refer to genes, to phenotypes, or both? For example, if there are two alleles that lead to differences in the structure of the D2 neuroreceptor, ...
3
votes
2answers
238 views

Two subunits connected by only one disulfide bridge: quaternary structure?

I've always simply assumed quaternary structure to be characterized by non-covalent interactions such as hydrogen bonding, van der Waals interactions and whatnot. However, if two distinct polypeptides ...
29
votes
3answers
2k views

Why is polyploidy lethal for some organisms while for others is not?

Polyploidy is the multiplication of number of chromosomal sets from 2n to 3n (triploidy), 4n (tetraploidy) and so on. It is quite common in plants, for example many crops like wheat or Brassica forms. ...
12
votes
2answers
139 views

How to decide which is the correct scientific name for a particular species

To start with, I am not a person having sound knowledge in biology. When I started my search for phyto-chemicals in a particular family in the plant kingdom, I got confused. The scientific papers use ...

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