6
votes
2answers
176 views

Hamilton's inclusive fitness approach

The underlying intuition of Hamilton's model of inclusive fitness is that we should study social behaviors from the point of view of actors -- rather than the recipients. To build his model, Hamilton ...
10
votes
3answers
1k views

Why did humans become bipedal?

Somewhere in evolutionary history homo started walking upright and became bipedal. You hear these hypotheses that, by walking upright, they could see better across the grassy savannas to escape ...
1
vote
2answers
135 views

What is the effect of persistent hypothermia on cardiac performance?

I define persistent hypothermia in this thread about the mechanisms of persistent hypothermia. The Graph of Katzung et al. in Pharmacology about Heart Failure: I am thinking which parts here are ...
3
votes
2answers
175 views

Is it possible to move your arms above your head when handcuffed in the back?

This move was seen in Pitch Black and i wonder if it is possible at all. Say you are handcuffed to a pole, hands in the back, and the pôle is a little higher than your head. You just want to do a ...
1
vote
1answer
70 views

Protocol for checking pipette calibrations using absorbance readings of a dye in solution?

I've been looking around the net looking for a nice protocol to validate micropipette calibrations using absorbance readings of a dye in solution. Does anyone have one they can share? I'd highly ...
1
vote
2answers
238 views

What is the importance of urea in mass spectrometry?

What is the importance of urea in mass spectrometry? We use 8M urea to FASP our proteins prior to mass spectrometry. What is the significance of using 8M urea? and how does it affect the proteins?
5
votes
1answer
418 views

What physics knowledge can be applied to biology of organisms and ecosystems?

In the wiki page of Biophysics: Biophysics spans all scales of biological organization, from the molecular scale to whole organisms and ecosystems. But after searching on the internet; the ...
3
votes
2answers
162 views

How do humans perceive time?

We can see length, and other physical quantities. We can perceive through our other senses like (temperature through thermoreceptors, weight through pressure receptors etc.). But how do we "sense" ...
3
votes
1answer
2k views

Does sample buffer require EDTA for protein separation on SDS PAGE?

In sample buffer preparation we add EDTA, but if SDS-PAGE is for protein then is it necessary to add EDTA in sample buffer? What is role of EDTA in sample buffer for protein separation for SDS-PAGE.
1
vote
0answers
36 views

How much does sleeping correlate with daily activity?

I'm a very lazy person. I spend most of my time in a chair, at a computer; I eat more than three meals a day. I don't do any sport, at all. What I want to know is: why do I need to sleep 8-12 hours ...
10
votes
3answers
201 views

Formation of Life

Originally, life evolved from non-living matter. Why is life only generated from other life nowadays, and why doesn't it evolve from inanimate matter, like it did originally billions of years ago, ...
7
votes
1answer
811 views

Are pulp cells (in oranges) normal plant cells?

Does a pulp cell contain all the elements that a 'normal' plant cell contains? I've searched for an hour to find more information about this but couldn't find anything useful. Is the pulp cell the ...
1
vote
2answers
97 views

Kinetic binding / unbinding constants of protein + mRNA ⇌ mRNP

I wish to find an order of magnitude for the binding/unbinding constants of mRNA and RNA-binding proteins. Suppose molecules A and B reversibly associate to give the complex C. Assuming the diffusion ...
1
vote
1answer
88 views

Species Identification (Insect)

I found this insect today in front of my room. I'm just curious to know what kind of insect it is? And, Is it poisonous? Location: India Thanks.
13
votes
2answers
803 views

Do electromagnetic waves outside the visible spectrum have any role in photosynthesis?

Does photosynthesis occur only in the visible spectrum? If there is a way to completely remove all other electromagnetic bands from the sunlight, including infrared (IR), will photosynthesis continue ...
3
votes
1answer
90 views

How would real-time blood glucose monitoring work?

Is it possible to perform real-time blood glucose monitoring using a wearable non-invasive device (similar to a fitness band measuring heart rate)? I'm aware that there are some devices in the market ...
27
votes
1answer
4k views

How many mosquitoes would it take to “drain” enough blood to put a person into shock?

I'm just curious, how many mosquito "bites" (mosquitoes which have removed blood from a person) would it take to remove enough blood to put a person into shock? (Putting aside all reasons why it ...
2
votes
1answer
71 views

How does the genetic material differ between dizygotic twins and ordinary siblings?

I am going to give a rough presentation on twin studies. The terms heritability and concordance are included already, but I struggle with understanding the difference of the genetic material of ...
1
vote
1answer
37 views

What controls Fructose regulation in plants?

Sugars are found ubiquitously in plants and are regulated. For sucrose it's pretty straightforward - it's basically kept at a low ish level, and put into storage or other intermediate compounds. ...
7
votes
1answer
85 views

Hamilton's derivation of direct fitness from his 1970 paper

In his 1970 paper "Selfish and Spiteful Behaviour in an Evolutionary Model", Hamilton uses Price's equation to derive his well-known rule $rb -c >0$. My question is about one of the steps in his ...
0
votes
1answer
134 views

What is the second phase of photosynthesis?

I really want to know what the second phase of photosynthesis (in the dark) is. I have a fair understanding of the first cycle where molecular oxygen is generated under the influence of light, but I ...
2
votes
1answer
68 views

How does steroid dependence occur?

I have seen on the internet that prolonged steriod treatment can result in the development of steroid drug tolerance leading to decreased hormone secretion. In turn this may lead to drug dependence, ...
11
votes
3answers
1k views

How many cells does the smallest animal have?

Note: question rewritten to prevent misunderstanding and make it more answerable I know that some small animals like C. elegans display surprising sophistication with a very small number of cells. ...
1
vote
1answer
160 views

C1q attachment to antibodies

After reading about complement pathway and the complement components, I was wondering, does the C1q component attach to the Fab fragment or to the Fc fragment? The pictures in Janeway's Immunobiology ...
0
votes
1answer
196 views

Can cfDNA testing distinguish results in the case of twins?

A fetus can now be screened for some of the more common genetic diseases and its sex determined from just a whole blood sample from the pregnant mother. Fetal DNA is abundant enough in the systemic ...
1
vote
1answer
63 views

What term describes insects that must eat protein to reproduce?

I know there is a specific term for insects that need to consume protein to produce viable eggs, as well as a term for those insects that don't need to consume protein to produce viable eggs.
3
votes
1answer
2k views

Why can blood group O be given to all blood groups?

Blood group O has antibodies against antigens A and B. Blood group A has A antigen. If someone with blood group A receives donor blood with group O, then anti-A antibodies in the donor blood should ...
3
votes
1answer
171 views

How fallible are DNA paternity tests?

Is it possible to get either a false positive or a false negative from a DNA paternity test and what would be the likely mechanisms behind this? For example, is it possible that a father's DNA could ...
0
votes
1answer
372 views

When do the spindle fibers attach to the chromosome

At what phase does this occur in mitosis (or even meiosis); some text books say prophase while others say metaphase.
5
votes
1answer
89 views

Is probability for double crossing over included in distance cM? [task]

We got this task: There are 3 genes (acb) on one chromosome (linked inheritance). Distance a-c = 12cM, a-b=16cM. Probability for double crossing-over (CO) is 0,6%. Find ratio of genotypes of ...
1
vote
0answers
108 views

Dopamine and other neurotransmitter release during music listening

A rather non-technical question here. Im looking for any studies that show a positive curve in respects to music sessions in humans and neurotransmitter release (specifically dopamine, epinephrine, ...
4
votes
1answer
8k views

What species of eagle pushes their young to teach them flying?

There are many references to eagle pushing their young off the nest to make them know how to fly, for example this motivational video. It is also described in this website: Let me show you "the ...
1
vote
2answers
82 views

Are there more true codes found in biology besides the central dogma?

I know each element of the central dogma is a code in the mathematical sense of finite-state machines. That is, DNA is transcribed into RNA, and RNA into proteins. What other examples are there of ...
0
votes
1answer
58 views

Supercomputer and undergraduates [closed]

Is it common for an undergraduate to run their thesis (evolutionary genomics) in a supercomputer? In my country, few supercomputers exist, but I'm not sure how it is for bachelors in the US or Europe. ...
1
vote
2answers
609 views

Growing E. coli at room temperature?

If I were to do a blue/white selection of transformed E. coli on LB agar ampicillin plates at room temperature (23⁰C) for about 2 days and 18 hours, will I run into the issue of satellite colonies or ...
2
votes
1answer
56 views

What equipment is needed to perform simple plant electrophysiology?

What is the minimum needed equipment to perform simple plant electrophysiology? I am looking for some simple experiments that I could run at home for learning. Ideally, I would transfer the skills to ...
3
votes
1answer
181 views

Fecundity per woman in early humans

The average fecundity per woman varies a lot from country to country. I call average fecundity per woman the average number of born children per woman. In Homo sapiens, what was the average fecundity ...
4
votes
1answer
142 views

Miscarriage in early humans

Today, about 10 to 20 percent of known pregnancy end in miscarriage. Pregnancy is a biological process that has been very well studied by medicine. As a result, modern medicine helps a lot to prevent ...
5
votes
1answer
88 views

Survival curve in early humans

The survival curve/function describes the probability of a given individual to survive to age $x$. In humans, today's survival function is very much influenced by medicine. This leads me to wonder ...
2
votes
0answers
71 views

How does the population fitness changes after a change in mutation rate

The mean population fitness as given by mutation load theory depends only on the genome-wide mutation rate ($U$). My question is: how many generations is needed to reach a new mutation load ...
5
votes
3answers
214 views

Which fruit compounds affect the speed of fructose absorption?

Blood fructose levels are not regulated by insulin in the human body. This means that the body absorbs pure fructose very fast, and it raises the blood fructose levels rapidly. Do fruits/ vegetation ...
0
votes
2answers
197 views

What triggers programmed cell death in humans (from outside the cell)?

What triggers programmed cell death in humans? Is it decided by the brain (for the entire body)? Or is it a local decision of a cell by its environment? Something else? I realize that there might be ...
1
vote
1answer
43 views

Why does renal artery stenosis lead to activation of Renin-Angiotensin system?

To my current understanding, stenosis or narrowing of the arteries would mean higher blood pressure, similar to atherosclerosis. So the Renin system should be suppressed to counter the high blood ...
2
votes
1answer
145 views

Production of processed Insulin in bacteria

Genetically-engineered bacteria are used to produce insulin in industry, but as far as I know, the bacteria can produce only proinsulin. Why is that? What happens in the human body in order to make ...
0
votes
0answers
73 views

How to measure concentrations of different metals from the environment?

Suppose that different kind of metals and chemicals (e.g. magnesium, sodium, copper) got transmitted to environment e.g. as a cause of an accident. How would measure the levels of those metals and ...
1
vote
2answers
40 views

awakening effects of light

I tried reading by light from a neighbouring room and felt sleepier than if my own lights were on. Is there a formula for the intensity of light vs physiological preparation for sleep(calcium, ...
5
votes
1answer
196 views

What's the worst that can happen from too much sleep deprivation? Can you die?

It is well known that sleep deprivation causes considerable discomfort in humans (and has even used as a form of torture), but nevertheless there have been people who went through protracted sleep ...
4
votes
2answers
176 views

IgA complement activation

Recently, I have been reading Janeway's immunobiology and had a question on immunoglobin A. I read that IgA activates the complement pathway using the Fab fragment of the IgA. How does IgA do that? I ...
0
votes
1answer
54 views

Taste of salt water

I had a question relating to chemistry and biology, so please tell me if this is suited better for the Chemistry website. My question was, if water dissolves salt by separating the two ions, the Na+ ...
5
votes
1answer
93 views

Are there any known health benefits / risks from milliampere current (0.1-2 mA) on forehead?

This is about devices like that sold by foc.us that allows user to apply a small current on a specific part of the forehead. For the sake of this question I use the foc.us "gamer" model as example. ...

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