6
votes
1answer
897 views

Examples of intracellular parasites of medical or economic importance?

What are examples of intracellular parasites of medical or economic importance? I have read that Xanthomonas oryzae is an intracellular parasite in rice that produces proteins able to cause changes in ...
13
votes
3answers
3k views

When has an organism evolved enough to be called a new species?

Imagine that we take a population of horses, split them in half and place them in completely different environments. The two species will evolve separate from each other and because the environment is ...
0
votes
1answer
509 views

Are there examples of the green beard effect in humans?

Green-beard effects are genes that: Produce an effect that can be detected Produce preference to others with the same effect Are there any examples of this in humans?
9
votes
3answers
1k views

Why does the butterfly have a cocoon stage in its life cycle?

Why does the butterfly have a cocoon stage in its life cycle? It could have simply grown up within the egg/cocoon, and emerged as a butterfly. Instead it is first an egg, then a worm, then a ...
2
votes
2answers
163 views

Can the body of any organism on Earth live without impairment both in vacuum, and within Earth's atmosphere?

I know from reading that a human in vacuum needs a space-suit to survive. Is the body of any organism on Earth capable of living equally in vacuum, and on/below Earth's surface within the ...
3
votes
2answers
459 views

Why Didn't Evolution Cause the Human Body to become Streamlined?

If streamlining makes movement/locomotion quicker and easier, why didn't the apes evolve into life-forms that had streamlined bodies (much like fish)?
10
votes
3answers
11k views

Hoechst or DAPI for nuclear staining?

When is it best to use Hoechst vs. DAPI for nuclear staining? They seem to be very similar on paper. Are there situations where one is clearly preferable?
3
votes
1answer
4k 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
143 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
164 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
59 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
8k 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
908 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
125 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
95 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
513 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
68 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
121 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
134 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
309 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
258 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
446 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
89 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
605 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 ...
9
votes
3answers
254 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
291 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
11k 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
104 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
147 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
249 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
207 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?
7
votes
1answer
344 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
36 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
78 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
297 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
130 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
296 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
301 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
161 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
6k 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?
16
votes
5answers
782 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
2k views

What are the units of Q10 (temperature sensitivity)?

$Q_{10}$ is the increase in a rate (e.g. activity of an enzyme) observed with a 10° temperature increase. According to Wikipedia: ...
4
votes
2answers
84 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
361 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
695 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
1k 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. ...

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