1
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2answers
53 views

Book recommendation on population/evolutionary genetics?

I have recently been involved in collaborations that require me to model the population genetics of eukaryotic populations. I fear I may either be "re-inventing the wheel" or making conceptual ...
1
vote
1answer
39 views

What can cause the swelling in high protein diet of Whey proteins?

I am thinking what can cause the swelling of high protein diet of Whey proteins. Liver does breaks those proteins to branched chain amino acids (BCAA), which can cause this swelling. However, I am ...
1
vote
2answers
80 views

Which was the last significant event in human evolution? What's next?

At 10.000 BC(12 ka) we became the last of the Homo species on Earth, in evolutionary terms this is a very little time range to something happen but I'm wondering ...
1
vote
1answer
24 views

Coalescent Theory - Probability for $k$ alleles that of one coalescence event occured $t+1$ generations ago

From this textbook Under the wright-Fisher model of genetic drift and under the assumption that all alleles are neutral, the probability that $k$ alleles had $k$ distinct parent alleles the previous ...
2
votes
0answers
39 views

Average face shape

I am doing face detection application where every face detected is inside a rectangle. The rectangle always contains some background behind the face and now I need to extract as much of the face as ...
0
votes
1answer
24 views

Development of vitreous humor

I have tried reading about development of vitreous humor but it is all very confusing. When does it first developed ? Does it renew itself ? Please provide reliable sources..
4
votes
3answers
97 views

Does our eyeball increase in size as we grow?

Does the size of the eye increase as we develop from the stage the complete eye first forms to infancy and then to adulthood ?
3
votes
1answer
106 views

Will neurons live after the death of a human? If so, how long?

I don't know if this is correct or not, but I have heard this from a friend and I want to get a clear explanation about this.I hope there is some one who can help me.
0
votes
0answers
7 views

What is the entry location into the heart for different autonomic stimuli?

I first had an intuition that the entry location is near sinus node, but now I am thinking that the location is near AV node, at least for some myocardial infarction patients. Physically, it is a more ...
2
votes
3answers
54 views

How do a viruses or bacteria survive outside the body long enough to spread?

Say I cough on my table, then someone else touches it and picks up something I've got... how is it that these things can live outside the body, how long can they manage it, and how long is generally ...
3
votes
1answer
31 views

Why are many anti-malaria drugs gap junction antagonists?

Why are many anti-malaria drugs gap junction antagonists? My professor recently just mentioned that many of the anti-malaria drugs block gap junctions. i am wondering if this blocking is important ...
3
votes
1answer
38 views

Why mosquito bite is confined to a certain shape?

I think this problem should be asked in a physiology forum rather than biology@ stackex but I'll give it a try. So my question is simple - why a mosquito bite is usually confined to a certain shape ...
0
votes
0answers
17 views

Most human-like teratoma ever recorded?

I'm curious to learn about the most human teratoma ever recorded. By most human I mean the teratoma which most resembles the form of a human being. I suppose there are several criteria which would ...
2
votes
4answers
97 views

Why do the humans become sleepy after meals?

I don't know about all the mankind, but I know enough people, who becomes sleepy after their meals. Also, I'm not sure, what kind of food do they consume, but I personally get sleepy almost from any ...
1
vote
1answer
13 views

Is there a Lyme disease vaccine?

Each Spring, our local health unit begins its campaign of Lyme disease and tick-bite awareness. I was wondering if there has ever been a vaccine available, and if so, what antigen does it target?
1
vote
1answer
41 views

Does recombination increase the additive genetic variance for fitness?

On this article, first column, eighth line of the introduction: By bringing together favourable alleles from different chromosomes, sex and recombination increase the additive genetic variance for ...
2
votes
2answers
33 views

Role of Melatonin in Circadian Rhythm

Melatonin regulates the wake-sleep cycle by causing drowsiness and lowering body temperature, but which specific chemical pathways lead to this drowsiness?
1
vote
1answer
42 views

Missing 4$H_2O$s (per glucose) in Cellular Respiration… Where can they be?

I having trouble understanding the equation of the cellular respiration. The thing that bothers me is the number of $H_2O$ molecules. Generally, cellular respiration is written thus : $C_6H_{12}O_6 + ...
3
votes
1answer
63 views

How does GC-content evolve?

Background GC-content refers to the frequency of base pairs that are either C or G in the genome, or in other words the number of GC base pairs divided by the addition of the number of GC base pairs ...
0
votes
1answer
26 views

How do I determine the parental type here?

Please consider the following question: You cross Drosophilia and receive the following offspring: 965 wild-type, 944 black- vestigial, 206 gray- vestigial, and 185 black- normal. Explain your ...
0
votes
1answer
17 views

Do trees have no set lifespan and “quite”immortal?

Many trees survive centuries and die only in disasters like storms and lightnings or infections. So do they have no set life span? Are they exceptionally resistant to genetic mutations and have very ...
6
votes
1answer
184 views

If all B cells are present at birth, why should the primary response to an infection take longer than the secondary response?

When learning about the immune response, my teacher mentioned that all the bodies B cells are present at birth, and there is one to counter every disease. But if this is the case, why should the ...
1
vote
0answers
24 views

Number of autoregulation and FFL motifs in a network

Suppose we have a network with N* nodes (N* is the number of internal nodes). Every directed link in this network exists with probability p. What would be the number of: motifs that are ...
5
votes
3answers
93 views

What prevents predator overpopulation?

I've often heard that a population, human or otherwise, will continue to grow as long as there is food available (assuming nothing else is killing them off). It makes sense: if you have food you can ...
6
votes
3answers
882 views

Why do parasites sometimes kill their hosts?

It's bothered me for a while now. I understand why a parasitoid would do this, as it only temporarily requires the host, and that not all parasites kill their hosts. There seems to be no evolutionary ...
2
votes
1answer
17 views

For emphysema, which of the respiratory volumes is effected. I have a couple of educated answers

It could be the tidal volume because it effects how a person inhales and exhales normally. It could be the residual volume and functional residual volume, because it increases its amount. Because it ...
1
vote
1answer
26 views

Earwax versus Mucus

Something I have wondered for a while is why have two different primary defense mediums, ie earwax and mucus, that perform the same function? As far as I know, mucus and earwax are both part of the ...
5
votes
3answers
391 views

Evolution: How could all useful traits evolve simultaneously?

I have a basic question about evolution, for which I never found an answer. I understand how evolution works if we focus on one specific organ or trait. With each generation, some organism is more ...
3
votes
2answers
78 views

Heterozygosity under genetic drift

The wright-Fisher model of genetic drift is: $$p_{ij} = \binom{2N}{j}\left(\frac{i}{2N}\right)^j \left(1- \frac{i}{2N}\right)^{2N-j} $$ ,where $\binom{2N}{j}$ is a binomial coefficient. From this ...
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 ...
0
votes
0answers
11 views

Which is the best software for Molecular Biology Graphics? [closed]

Probably you have seen the beautiful graphics that appear on every article in Science or Nature. I want to get the closer to that result making Molecular Biology graphics with a simple and easy-to-use ...
2
votes
1answer
67 views

dopamine paradox in Schizophrenia

If there is more dopamine action in the mesocortical pathway in Schizophrenia, then the patients should always be in euphoric state. But instead patient lacks motivation and don't want pleasure. Why?
1
vote
1answer
24 views

Correlating B-lactamase expression to absorbance

When penicillin-resistant bacteria are grown in liquid culture media, B -lactamase is secreted into the medium. The supernatant of such a medium can be assayed for B- lactamase activity. Culture ...
4
votes
1answer
119 views

What exactly makes bananas go brown?

I know that often oxidation processes are mentioned when referring to the color change from yellow to brown in bananas (specifically: those that you get everywhere in supermarkets, with no seeds). ...
0
votes
0answers
12 views

Distribution of Physarum polycephalum tubes during starvation phase

So I have been trying to find an answer to this question in the literature but to no avail. I am looking at the Tero and other articles on the slime mold Physarum polycephalum. I understand the models ...
2
votes
1answer
118 views

What is the beneficial function of IgE antibody?

Dont tell me the "function" of IgE is to cause allergy ! In whatever texts I have seen it is written that IgE is important to cause allergies but what is the beneficial function of IgE ? Why was it ...
0
votes
0answers
6 views

What are the mechanisms of disabling extrinsic control of heart?

I started this thread by thinking this question but I developed it further below What is the mechanism maintaining refractory period of pacemakers? My conjuncture is that the mechanism is the ...
0
votes
0answers
22 views

Is there a biological reason for spreading food intake into breakfast-lunch-dinner?

I keep hearing over an over how humans can satisfy their entire daily caloric need in one sitting at a fast food restaurant. At the same time I'm looking at the kitchen plates, cups, etc, and they ...
1
vote
2answers
34 views

Maintaining purebred pedigrees and how to lessen chance of getting disease?

Many breeds of dogs are known for a high incidence of genetic disorders. German shepherd and Saint Bernard dogs are predisposed to developing a crippling condition called hip dysplasia. Q: What ...
1
vote
2answers
43 views

Can 'hardware' thermalization explain memory decay?

Often we are able to memorize very precise bits of information (exact addresses, birthdays of inlaws, number of dirty socks under the bed), but over time our recollection tends to become fuzzy. We no ...
0
votes
0answers
7 views

Which reflex arcs work in Heart with extrasystoles?

I am researching what is triggering the extrasystoles - initial idea from this thread about Which ionic channels of Pacemakers can work in very low frequencies in extrasystole? I am interested in the ...
0
votes
1answer
5 views

Which ionic channels of Pacemakers can work in very low frequencies in extrasystole?

At frequency 0-3 Hz. Like computer processors which can work at low frequencies and controlling under- and overvoltage. Normal most significant channels are Ca2+ and K+ that are changing. However, I ...
10
votes
2answers
245 views

How does the genetic code evolve?

After looking at this question, some other questions poped in my mind. The DNA code is redundant, there are 20 amino acids for 64 possible nucleotide combinations. Therefore some amino acid are coded ...
3
votes
1answer
49 views

relative-rate of evolution

I am supposed to calculate the relative rate of evolution of two sequences (human and sheep) with a chicken serving as the outgroup. The sequences are pretty long, so I will just create a short ...
0
votes
0answers
16 views

Book-recommendations on virus evolution [closed]

I am seeking for a good book on… Virus evolution Viral population genetics Theoretical virus evolution Mathematical modeling of virus evolution Evolution of virulence Intra and inter-specific ...
2
votes
1answer
227 views

Why do three nucleotides code for one amino acid? Why not 5 nucleotides? [duplicate]

We all know why there are 3-base codons, and why there aren't any 2-base codons. But why is there not a 4-base a 5-base codon?
0
votes
1answer
25 views

how many chemcial species on average in a typical plant and animal cell

I want to know what sort of range there is on the number of different chemical species in a typical plant and animal cell. Failing that, some specific examples (with sources please) Thanks
0
votes
0answers
14 views

Simultaneous depolarisation of Sinus Node and AV node as extrasystole in myocardial infarction patient

Assume you have a patient 68 years old with previous myocardial infarction (Actually patient 201 in MIT-BIT arrhythmia database). Assume that AV node depolarises strongly. However, at the same time, ...
1
vote
1answer
25 views

Troubleshooting for Agarose Gel Electrophoresis

SI ran my 2% agarose gel on constant voltage (100 V). For a few times it worked at CV but, after a week or so the machine would automatically switch to constant current by itself. And this only ...
1
vote
1answer
15 views

Usage of the taxonomic classification “Pinnipedia”

According to ITIS the classification Pinnipedia is invalid, and it is proposed to rather use Caniformia. The later group however includes a range of terrestrial animals as opposed to the pinnipeds ...

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