15
votes
0answers
168 views

Phagemid display

If I'm using a bacteriophage for phage display and I'm trying to avoid avidity effects by using a helper phage what would be the best way to maintain a large library size while keeping everything ...
11
votes
0answers
80 views

Haidinger's brush: Is this a by-product of the eye's physics, or are there any evolutionary grounds for it?

The human eye is, very subtly, sensitive to the polarization of light. This is an effect known as Haidinger's brush (see Wikipedia article of this name). What, if anything, is known or at least ...
11
votes
0answers
189 views

Do the majority of fish lack scales on their heads?

Based on pictures, it seems to me that a vast majority of fish species that have scales do NOT have scales on their heads. Is that fact true? To make this properly answerable: lets' define a ...
8
votes
0answers
103 views

paralogue genes in genome-wide association studies?

Has anybody tested if paralogous genes are over-represented among the genes identified by genome-wide association studies (GWAS)? For example, if a GWAS study finds 200 genes associated to the ...
7
votes
0answers
30 views

Beginning of the urogenital system

Are any invertebrate nephridia (proto/meta) homologous with vertebrate kidneys in the sense that embryologically they also begin together with the genital system? When did the embryologic association ...
7
votes
0answers
233 views

Yellow/Orange Fungus on Oak Tree

What is the fungus pictured below? The photo was taken October 6, 2013 near San Antonio, TX. I have Googled it and my results suggest Laetiporus root rot (Laetiporus sulfureus). According to this ...
7
votes
0answers
103 views

How reversible is DAT upregulation from long-term ADHD medication use?

A mechanism for ADHD stimulant medication tolerance has now been found. See http://neurosciencenews.com/adhd-medication-patient-brains-adapt-dat/. Here's the thing though: what exactly is the ...
6
votes
0answers
137 views

Correlation between genome size and mutation rate?

Martin Nowak in his book "Evolutionary Dynamics" talks about a given correlation between genome size and mutation rate. What correlation does exactly exist between these two concepts? Is it a ...
6
votes
0answers
125 views

Do fake wasp nests actually fool wasps?

I have seen fake wasp nests sold as a deterrent against wasps and similar insects. Do they really work? Is there some scientific evidence for it? A related link: ...
6
votes
0answers
121 views

How is hibernation/aestivation different from anesthesia?

How do hibernation/aestivation happen? I read on wikipedia that a squirrel injected with the body fluids of a hibernating fellow is more prone to hibernation. If hibernation/aestivation are driven ...
6
votes
0answers
53 views

Using the IMGT/GENE-DB service to find RSS

I'm trying to get the data for the Human and Mouse 12 and 23 Recomination Signal Sequences (RSS), to run a classification algorithm on it. I'm not a biologist, so I apologise in advance for my ...
6
votes
0answers
102 views

What is the fastest way to build an alanine scanning library?

For interfacial studies, I would like to build an alanine scanning library for one of my proteins examining 20 sites. I will ultimately express the gene using E.coli cell-free protein synthesis. I ...
6
votes
0answers
65 views

Pancretic Acinar Cell - ATP, calcium concentration data

I need to find a decent source of data for concentration of ATP and calcium in the pancreatic acinar cell. So far all I can find is ATP or calcium 'levels' based on fluorescence , which are not ...
5
votes
0answers
29 views

E coli cotransformation efficiency

What is the E coli transformation efficiency for 2 plasmids? Are any studies that have looked at the correlation between number of plasmids transformed and transformation efficiency? Is there a ...
5
votes
0answers
25 views

Linkage disequilibrium with $n_l$ loci $n_a$ alleles

Linkage disequilibrium $\left(D\right)$ for two bi-allelic loci is defined as: $$D=X_{11}X_{22} - X_{12}X_{21}$$ , where $X_{11}$, $X_{12}$, $X_{21}$, X$_{22}$ are the frequencies of the haplotypes ...
5
votes
0answers
32 views

Absorption rate of Infrequently eating animals?

Clearly, creatures such as us humans, after vastly increasing the entropy of our food, expel most of the mass that we consume. Some creatures, however, do NOT get the opportunity to eat nearly as ...
5
votes
0answers
58 views

is it possible to completely reconstruct a family tree by DNA comparison alone?

Having DNA samples of all or almost all members of a population of, say, a few hundred or thousand individuals, is it possible to draw the entire family tree of those individuals? (Let's not assume ...
5
votes
0answers
143 views

How long can a bee surive in a jar?

So, some people and I encountered an adventure game where you have a bee in a jar and need to move it from place to place before it suffocates, and someone tried to find out how long a bee would ...
5
votes
0answers
62 views

Neuroendocrinal mechanism of parturition

My book reads, "The fetus signals that it is mature by secreting certain hormones that diffuse across the placenta into mother's blood and cause the secretion of oxytocin from her posterior ...
5
votes
0answers
37 views

Reformulation of Hamiton's rule

Who (and in which article) was the first to reformulate Hamilton's rule using the letters $B$ and $C$?. See below comments on this reformulation. Hamilton, in his 1964's article gave a mathematical ...
5
votes
0answers
43 views

How well supported is the hypothesis that aging is mainly caused by the number of mutations in tissues?

I heard the hypothesis, that the (main) reason of aging is the increasing number of mutations in body tissues. The higher the number of mutations is, the older tissue is. Is this true? And how well ...
5
votes
0answers
130 views

On average how many genes / alleles do people share?

I am curious about how much more a child can be alike to one parent than the other. If a child were to inherit all the alleles that are shared between both parents from one parent, but inherit all ...
5
votes
0answers
189 views

Reason for seeing grid-like patterns when strobing a solid black-white image?

I was trying to do some stimulation for SSVEPs by strobing a solid black square and a solid white square. Weird thing was, I ended up seeing weird grid like patterns that looked like this, always of ...
5
votes
0answers
80 views

Long term effects of “brain freeze” on the cerebral vasculature

According to one theory, ice cream headaches are caused by an increase in blood volume of the anterior cerebral artery: Another theory into the cause of ice-cream headaches is explained by ...
5
votes
0answers
98 views

Pharmacologically, can tricyclic antidepressants have a side-effect profile similar to neuroleptics?

Torticollis (wryneck, cervical dystonia) is a neurologic movement disorder causing involuntary muscle spasms in the neck. Often, neuroleptics can cause such a side effect. I'm wondering if this ...
5
votes
0answers
92 views

What temperature should mammalian B-Cells be stored at outside of the incubator?

I'm working with murine B-cells. The general protocol is to keep cells on ice to keep them from dying but I've noticed that it makes these cells aggregate and precipitate out. I've heard suggestions ...
5
votes
0answers
43 views

Providing small molecules to cells on a filter plate

Lets imagine that I have mammalian cells that I've immobilized on a filter. Now I want to keep providing small molecules to these immobilized cells without resolubilizing the cells. The caveat is ...
4
votes
0answers
22 views

Evolution of Chromosome Numbers

Some species have different numbers of chromosomes, as we all know. Throughout evolution, how was a species able to survive with an extra chromosome? How was this organism able to breed successfully ...
4
votes
0answers
41 views

Effective population size and overlapping generations

From this book; If generations overlap, then the effective population size $N_e$ does not equal the population size $N$. I know mathematical formulations in order to find the effective population ...
4
votes
0answers
44 views

Selection on linked loci in a diploid population

Let’s consider two linked loci $A$ and $B$ that are both bi-allelic. In consequence, we have four different possible haplotypes $A_1B_1$, $A_1B_2$, $A_2B_1$, $A_2B_2$, which frequencies are $X_1$, ...
4
votes
0answers
34 views

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

Because there's 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 ...
4
votes
0answers
108 views

How many loci explain 50%, 80%, 99%, … of the total genetic variance in fitness?

Standard models in population genetics look up at the evolution of few loci which impact fitness. The variance in fitness is determined by the genetic variance and the environmental variance (and the ...
4
votes
0answers
38 views

What are the lifetimes of cellular components on organelle or molecular level?

I was thinking that even though I know how generally the cell works, I don't really have a feeling of how volatile it is. I want to know what is the lifetime/turnover rate of different constituents of ...
4
votes
0answers
48 views

Why isn't RH disease present in other mammals?

Basically, I have read about RH disease, Its rare but it can happen when an RH + baby is conceived by an RH - mother. This raises many questions. I have heard this problem only happens with humans, ...
4
votes
0answers
42 views

Measuring fitness in drosophila

I am planning a fitness assay of Drosophila melanogaster. I'd like to get a good measure of lifetime reproductive success (lrs) but I don't want to count all the offspring produced over a lifetime by ...
4
votes
0answers
103 views

Genetic expression in interspecific hybrids

Referring to interspecific hybrids, I have the following two questions:- Quoting from wikipedia:- The offspring of an interspecific cross are very often sterile; thus, hybrid sterility ...
4
votes
0answers
37 views

Does DHA increase the effects of clarithromycin?

I've read on this publication that every drug that induces CYP3A can reduce the effectiveness of clarithromycin. Clarithromycin inhibits CYP3A. But it does not say anything about the opposite ...
4
votes
0answers
28 views

Calling for Free Online Data for Paediatric ECG?

I need free online data about heart murmurs to study these: heart murmur frequency , S2 heart sound frequency and its split, murmur timing, and duration, murmur intensity, S3 sound presence and ...
4
votes
0answers
96 views

Cytoplasmic determinants - protostomes and deuterostomes

Cytoplasmic determinants are spread unevenly in the egg, and so when embryo starts forming (cells start dividing), the determinants are also unequally divided between cell. This unequal distribution ...
4
votes
0answers
35 views

Is telomere shortening consistant over consecutive cell divisions from zygote to a differentiated cell?

Considering the complexity of embryogenesis, a temporal referance would be helpful to coordinate the developmental sequences during embryogenesis and fetal development which is to be completed within ...
4
votes
0answers
79 views

Identification of this Salamander

This salamander was found in a small forest pond somewhat near the Oregon coast. In the area are many rough skinned newts and a small number of another type of salamander that I still can't find the ...
4
votes
0answers
25 views

Are there any online resources one can use to access raw clinical trial data without having to contact those involved in the study?

I want to do some statistical analysis and I have a preference for real data so I was wondering if there's somewhere I can get such data for free without a heap of bother in phoning other those ...
4
votes
0answers
45 views

Why might you NOT observe a tradeoff between two life-history traits?

I have traditionally thought of and heard about life-history traits (e.g., size at first reproduction, number of offspring, size of offspring, survival, etc., etc.) as drawing from a finite pool of ...
4
votes
0answers
39 views

How significant is RNA degradation with removal of cap/polyA's in eukaryotes, or UTR's in prokaryotes?

Question is rather self-explanatory, but segmented into two parts. I'm attempting to make use of a repression system that employs cleaving RNA at specific areas with ribozymes with the intent of ...
4
votes
0answers
70 views

Model for fluctuating selection

Is there any mathematical model to predict the behaviour and long-term consequence of counter-acting selection at different time scale? For example, let's consider the bi-allelic gene $A$, with ...
4
votes
0answers
22 views

How to search for organisms by criteria such as growth substrate and overflow metabolites?

I'm looking for a database or a systematic way to search for organisms which meet certain criteria. My criteria descending importance are: growth substrate chemolithoautotrophy (on which substrate) ...
4
votes
0answers
36 views

Honeybee decision process: new food, new home, new threat

I have heard that honeybees send out scouts, then based on the scout reports more bees go then come back and report and so they are supposed to be efficient decision makers. Can you give as complete ...
4
votes
0answers
34 views

Selective Androgen Receptor Agonist

I'm looking for an inducer that strongly activates the androgen receptor, but not the glucocorticoid receptor that is not DEA regulated. I know that SARMS (Selective Androgen Receptor Modulators) are ...
4
votes
0answers
72 views

Is it possible to condition the body to reduce bruising?

I do combat sports, and in these sports there are a lot of hits that can cause bruising. I've found that, over time, physical conditioning can reduce and/or eliminate the bruising to the point where ...
4
votes
0answers
58 views

How do animals perform detailed active camouflage?

We often see videos of octopuses and chameleons changing their color to suit their surroundings. If it was a simple color change from white to red, it'd be understandable, but some of these animals ...

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