qid int64 2 112k | question stringlengths 61 6.7k | positives listlengths 1 1 | negatives listlengths 1 10 |
|---|---|---|---|
17,057 | <blockquote>
<p>Also, transplants from one identical twin to another are <strong>almost never</strong> rejected.<br />
<sub>[ Source: <a href="http://www.nlm.nih.gov/medlineplus/ency/article/000815.htm" rel="nofollow noreferrer">Medline Plus</a> ]</sub></p>
</blockquote>
<p>Why can a tissue from an <em>identical</em> t... | [
{
"answer_id": 17068,
"pm_score": 2,
"text": "<p>MattDMo, I think you're right on. Also remember the <a href=\"http://en.wikipedia.org/wiki/Thymus\" rel=\"nofollow\">thymus</a> is where T-cell recombination and maturation occurs during fetal development, and rates are highest during neonatal period thr... | [
{
"answer_id": 17059,
"pm_score": 2,
"text": "<p>This was too long for a comment, but I have absolutely no evidence for what I'm about to say :)</p>\n\n<p>It looks like that sentence was a little bit of hand-waving, as the author didn't want to categorically state that identical twin tissue would <stron... |
17,065 | <p>In math, there are special numbers, like Pi (3.14159...) and e (2.71828...). In chemistry, there's numbers like avogadro's number (6.0221413e+23). For example a circle can be defined in terms of 2 * Pi.</p>
<p><strong>Are there any significant constant numbers in biology that define the shape of an organism</strong... | [
{
"answer_id": 17067,
"pm_score": 4,
"text": "<p>I don't know if this is what you mean, but take a look at <a href=\"http://bionumbers.hms.harvard.edu/\" rel=\"nofollow\">BioNumbers</a>.</p>\n\n<p>Also, mathematical constants like pi are different from physical constants. Mathematical constants are true... | [
{
"answer_id": 17088,
"pm_score": 2,
"text": "<p>I think you have the direction of causality reversed. Due to either physical, chemical or dynamical properties of cells and organisms, it would certainly be possible to see patterns of constants emerge when making some measurements. I don't think you can ... |
17,081 | <p>In his song <a href="https://www.youtube.com/watch?v=ESFANzZTdYM" rel="nofollow">Lullaby</a>, Tim Minchin <a href="https://www.youtube.com/watch?v=ESFANzZTdYM?t=57s" rel="nofollow">sings</a>:</p>
<blockquote>
<p>Your nappy is dry and your tummy is full<br>
Of enough antihistamine to chill out a bull<br>
Yet s... | [
{
"answer_id": 17083,
"pm_score": 4,
"text": "<p>This song most likely refers to an <strong>off-label</strong> (<em>and usually <strong>inappropriate</em></strong>) use for certain antihistamines like <strong>Benadryl</strong>. They are sometimes used by parents to <strong>sedate their children</strong>... | [
{
"answer_id": 17082,
"pm_score": 2,
"text": "<p>This is not only happening in babies...\nIn short (I will look for some references later and edit the post) the antihistamines are effective in the whole body and block the histamines there. The antihistamines which cross the blood-brain barrier do the sa... |
17,104 | <p>I recently read about an experiment where they removed the dendrites and axons from rat neurons and placed them on a grid. After a while they started reconnecting and were able to learn things.</p>
<p>Since I'm trying to create a model simulating this, I'd like to know (as much as is needed to make it look at least... | [
{
"answer_id": 17291,
"pm_score": 4,
"text": "<p>I think I can partially answer you question. As far as I'm aware, there are many surface receptor molecules such as ephrins that are responsible for axonal guidance and dendritic repulsion in developing organisms such as flies (Drosophila). As you can tel... | [
{
"answer_id": 17302,
"pm_score": 3,
"text": "<p>In cases of severe head injury where a large portion of neurons and their connections get shredded. I don't think a neuron would be very choosy when presented with quite a few axons and lots of intracellular fluid </p>\n\n<p>There are coup and the contra... |
17,159 | <p>What is the difference between transformation and transfection? How do both of these methods work?</p>
| [
{
"answer_id": 17161,
"pm_score": 4,
"text": "<p>If you are interested in the history of molecular biology this is an interesting question. </p>\n\n<p>Basically transformation came to be used to describe experiments in which the phenotype of an organism was changed by the uptake of DNA, and because of t... | [
{
"answer_id": 17160,
"pm_score": 2,
"text": "<p>As far as I know (and I haven't found no evidence against it) this is mostly a semantic difference. Both processes describe the addition of genetic material into cells using various techniques. </p>\n\n<p>Transformation is here mostly used for bacterial w... |
17,170 | <p>I am trying to determine the "translated" meanings (not seeking the common names) of different insects, (presently some bees and wasps). Does anyone know of a printed or internet resource that defines the various names. I have one for plants, but not for animals. Knowing the (English) meaning of the Latin / Greek/... | [
{
"answer_id": 17161,
"pm_score": 4,
"text": "<p>If you are interested in the history of molecular biology this is an interesting question. </p>\n\n<p>Basically transformation came to be used to describe experiments in which the phenotype of an organism was changed by the uptake of DNA, and because of t... | [
{
"answer_id": 17160,
"pm_score": 2,
"text": "<p>As far as I know (and I haven't found no evidence against it) this is mostly a semantic difference. Both processes describe the addition of genetic material into cells using various techniques. </p>\n\n<p>Transformation is here mostly used for bacterial w... |
17,185 | <p>I need to draw simple, phylogenetic tree for kids lecture. </p>
<p>I am looking for an online tool where I can enter organisms (e.g., human, wasp, fungus) and get figure of a phylogenetic tree. Tree should be based on how close those organisms are (I don't need genome alignments).</p>
<p>Similar figure producing ... | [
{
"answer_id": 20273,
"pm_score": 4,
"text": "<p>As per your requirements I will suggest:</p>\n\n<p><a href=\"http://www.onezoom.org/\" rel=\"nofollow noreferrer\">http://www.onezoom.org/</a></p>\n\n<p><img src=\"https://i.stack.imgur.com/4IXP7.jpg\" alt=\"\"></p>\n"
}
] | [
{
"answer_id": 20271,
"pm_score": 2,
"text": "<p>I don't know what background you have given the kids or what level, but here's something we do in a non-majors freshman level biology course that could easily be adjusted. First, to get them thinking about trees and relationships, give them a simple famil... |
17,186 | <p>What are the functions of disulphide bonds between amino acids in proteins or peptides?</p>
| [
{
"answer_id": 20273,
"pm_score": 4,
"text": "<p>As per your requirements I will suggest:</p>\n\n<p><a href=\"http://www.onezoom.org/\" rel=\"nofollow noreferrer\">http://www.onezoom.org/</a></p>\n\n<p><img src=\"https://i.stack.imgur.com/4IXP7.jpg\" alt=\"\"></p>\n"
}
] | [
{
"answer_id": 20271,
"pm_score": 2,
"text": "<p>I don't know what background you have given the kids or what level, but here's something we do in a non-majors freshman level biology course that could easily be adjusted. First, to get them thinking about trees and relationships, give them a simple famil... |
17,207 | <p>I was at the park lying on the grass and its the third time I have seen them, I used to think they were parasites when I was like 7. It is the very small brown worm on the green leaf. It moves by squiggling. It comes in different colors but same size.</p>
<p><a href="http://postimg.org/image/ea3x2nw95/" rel="nofoll... | [
{
"answer_id": 35153,
"pm_score": 2,
"text": "<p>For me it looks like an <a href=\"http://en.wikipedia.org/wiki/Geometer_moth\" rel=\"nofollow noreferrer\">inchworms</a> which are the larvae of geometer moth or Geometridae.</p>\n\n<p>By your picture it is almost impossible to see of which type it is.</p... | [
{
"answer_id": 17379,
"pm_score": 2,
"text": "<p>Is this what you mean? </p>\n\n<p><img src=\"https://i.stack.imgur.com/popbq.png\" alt=\"wireworm\"></p>\n\n<p>It's pretty hard to tell from this photo, and I'm no entemologist, but to me, it looks like it may be a <strong>wireworm</strong>, a larvae of a... |
17,213 | <p>There's undoubtedly more than one way to do this, but if a DIY biologist were to attempt to detect food fraud (e.g. as done by students from <a href="http://conservationmagazine.org/2008/09/impostor-fish/" rel="nofollow">Stanford University</a> and <a href="http://www.nytimes.com/2008/08/22/science/22fish.html?_r=0"... | [
{
"answer_id": 17221,
"pm_score": 4,
"text": "<p>There are several ways you could go about identifying species through DNA. If you want to do everything yourself, the simplest option in terms of equipment needed consists of evaluating fragment lengths observed during gel electrophoresis after amplifying... | [
{
"answer_id": 17267,
"pm_score": 1,
"text": "<p>This can in principle be done at least partly with DIY methods, by using PCR followed by gel electrophoresis. The DremelFuge, OpenPCR, and Blue Transilluminator would be the primary tools, along with pipettes, test tubes, autoclave (or equivalent), etc.</... |
17,245 | <p>If a person's head was cleanly and rapidly decapitated by a sharp blade slicing through the neck, such as would happen on the guillotine, could that person remain conscious? If so for how long? Long enough to be aware of (the head) falling down and hitting the ground? </p>
<p>Obviously it would be brief due to lack... | [
{
"answer_id": 17247,
"pm_score": 4,
"text": "<p>According to <a href=\"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3029360/\">this</a>, in rats it takes about 17 seconds after decapitation for the EEG to become iso-electric. But there is no known correlation between EEG and consciousness. Also at 50-80... | [
{
"answer_id": 17263,
"pm_score": 0,
"text": "<p>I remember reading that during the French Revolution Antoine Lavoisier arranged with his assistant condemned to death to blink after the cut off if he still had conscience (Lavoisier was to call his name first to limit automatisms). He reported a possibil... |
17,246 | <p>It is obviously very onerous to generate heat at all, although it has advantages. We don't have to lie on the sun like a crocodile to get warmer. And we avoid the freezing of our body water by out own means. But wouldn't just a little of heat be enough? </p>
<p>Why do humans go as far as 37 C? Couldn't we just have... | [
{
"answer_id": 17247,
"pm_score": 4,
"text": "<p>According to <a href=\"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3029360/\">this</a>, in rats it takes about 17 seconds after decapitation for the EEG to become iso-electric. But there is no known correlation between EEG and consciousness. Also at 50-80... | [
{
"answer_id": 17263,
"pm_score": 0,
"text": "<p>I remember reading that during the French Revolution Antoine Lavoisier arranged with his assistant condemned to death to blink after the cut off if he still had conscience (Lavoisier was to call his name first to limit automatisms). He reported a possibil... |
17,264 | <p>I couldn't seem to find one elsewhere, at least not with a scientific source.</p>
<p>It would seem as it's quite a striking feature there would be an advantage it would infer.</p>
| [
{
"answer_id": 17287,
"pm_score": 4,
"text": "<p>As your commenters have suggested, no.</p>\n\n<p>In order for an explanation to be a <strong>good</strong> evolutionary explanation, it needs to have a testable hypothesis and a mechanism to test it. </p>\n\n<p>The most common mechanism for testing the cr... | [
{
"answer_id": 17417,
"pm_score": 0,
"text": "<p>I quite like the explanation I found on the website of \"Exploring the BioEdge\". Robin and Honeybadger explain the black and white colouration as follows: To minimize the risk of being attacked by the tiger, the colouration of the giant panda is aposemat... |
17,276 | <p>There are two different cell lines but we do not know that these cell lines have Gs or Gi proteins, associated with their G-protein coupled receptors. If we wants to know about this. Can we design a experiment through which we would be able to identify specific Gs or Gi proteins in cell lines?</p>
| [
{
"answer_id": 17414,
"pm_score": 3,
"text": "<p>Bez experiments are too difficult and costly you don't need to do that.</p>\n\n<p>Take, label samples then apply ligands and sustenance. The inhibitory will have have a slower rate of <strong><em>growth</em></strong> not death and use a control with repli... | [
{
"answer_id": 17337,
"pm_score": 2,
"text": "<p>EDITED ANSWER</p>\n\n<p>Based on comments and responses my original answer to this question received I have decided to edit the answer and respond to some questions.</p>\n\n<p>Since I work on proteins, I tend to favour protein based approaches specially w... |
17,320 | <p>I thought that the definition of a definitive host was that the parasite had to sexually reproduce in that particular host. </p>
<p>I've been told that mosquitoes are the definitive host for the plasmodium parasite, but I thought that the fertilization (and thus the sexual reproduction) takes place in the human?</p... | [
{
"answer_id": 17321,
"pm_score": 4,
"text": "<p><em>Plasmodium falciparum</em> (the main causative agent of malaria) and other <em>Plasmodium</em> species have a very complex life cycle, with stages in the female host <a href=\"http://en.wikipedia.org/wiki/Anopheles\" rel=\"nofollow noreferrer\"><em>An... | [
{
"answer_id": 56874,
"pm_score": 0,
"text": "<p>The answer contains a lot of information, some incorrect, and does not answer the question.</p>\n\n<p>The mosquito is the definite host of plasmodium, despite the humanocentric way this parasite is always looked at.</p>\n\n<p>What happens in the human is ... |
17,370 | <p>An <a href="https://pets.stackexchange.com/questions/3159/what-is-an-acceptable-flea-treatment-for-kittens/3176#3176">answer at Pets</a> suggested using dawn dish soap to kill fleas. I did a little looking around, and found several references supporting the idea. Most of what I found was in 'selfhelp' and 'save a d... | [
{
"answer_id": 17477,
"pm_score": 5,
"text": "<p>First part of the answer - Yes fleas (Siphonaptera) can be drowned. But not as easily as the internet would lead you to believe.</p>\n\n<p>There are many claims on the internet (and printed works) expounding on how simple it is to drown fleas. The best s... | [
{
"answer_id": 37134,
"pm_score": 2,
"text": "<p>You have to use Lemon Dawn specifically because they have <a href=\"https://en.m.wikipedia.org/wiki/Limonene\" rel=\"nofollow noreferrer\">Limonene</a> and <a href=\"https://en.m.wikipedia.org/wiki/Linalool\" rel=\"nofollow noreferrer\">Linalool</a> from ... |
17,441 | <p>It is said that genes define how we look physically and psychologically; so for example if a male human sperm carries a certain number of genes, say x, and a female carries y, then mathematically there would be m genes from the male and n from the female, and a finite total available. Could there be people identical... | [
{
"answer_id": 17478,
"pm_score": 3,
"text": "<p>For ease of explanation let me first tell you that the \"genetic makeup\" is called \"genotype\" and that \"how we look physically and psychologically\" is known as \"phenotype\". These are not complete definitions of the terms but this should help you un... | [
{
"answer_id": 17475,
"pm_score": 1,
"text": "<blockquote>\n <p>It is said that genes define how we look physically and psychologically</p>\n</blockquote>\n\n<p>I would be skeptical of anyone saying this. Nature vs. nurture is far from settled, especially in psychology. The trend seems to be that many ... |
17,498 | <p>I am wondering exactly what a-fib is (causes and symptoms).
<p>
I would really appreciate having a sample of an EKG with it (because in my limited research, I have found it nearly impossible to find just a sample piece of an EKG that has a-fib on it) with your answer, so I can actually get an idea of what it looks l... | [
{
"answer_id": 17555,
"pm_score": 4,
"text": "<p>A human heart can be viewed as 2 hearts, the left and the right heart, each consisting of an atrium and a ventricle. The atrium's function is to fill the ventricle with as much blood as it can and the ventricle then pump the blood away. Also there is a sy... | [
{
"answer_id": 27565,
"pm_score": 2,
"text": "<p>Remember that except for the concluding pathway through the A-V bundle, the atrial muscle mass is separated from the ventricular muscle mass by fibrous tissue. Therefore, ventricular fibrillation.</p>\n\n<p>The mechanism of atrial fibrillation, except tha... |
17,532 | <p>The Price equation describes mathematically the evolution of a population of units from one generation to the next. </p>
<blockquote>
<p>$\bar{w}\Delta \bar{z}$ = $Cov (w_i,z_i) $+$ E(w_i\Delta z_i)$</p>
</blockquote>
<p>I would like to know how to actually employ the equation to some data. Perhaps a simple onli... | [
{
"answer_id": 17560,
"pm_score": 3,
"text": "<p>Here is a simple example using your data in which both terms of the Price equation are needed, since the value of the character for $z_2 $ changes in the second generation. I used your suggested change $z_2'=(9\\cdot 2 + 1\\cdot 3)/10 = 2.1$. </p>\n\n<p>T... | [
{
"answer_id": 17533,
"pm_score": 2,
"text": "<p>This is a nice numerical walk-through and explanation, see this <a href=\"http://www.tedpavlic.com/post_price_equation.php\" rel=\"nofollow noreferrer\">webpage</a>.</p>\n<p>As requested I've sketched out a solution to the specific case above.</p>\n<p>A n... |
17,539 | <p>I fail to see how natural selection can build any kind of new functionality.</p>
<p>New functionality in a design requires sacrificing a complex series of meanwhile useless steps before the new functionality works and becomes advantageous.</p>
<p>For example, if I want to upgrade a stationary chair to a wheelchair... | [
{
"answer_id": 17560,
"pm_score": 3,
"text": "<p>Here is a simple example using your data in which both terms of the Price equation are needed, since the value of the character for $z_2 $ changes in the second generation. I used your suggested change $z_2'=(9\\cdot 2 + 1\\cdot 3)/10 = 2.1$. </p>\n\n<p>T... | [
{
"answer_id": 17533,
"pm_score": 2,
"text": "<p>This is a nice numerical walk-through and explanation, see this <a href=\"http://www.tedpavlic.com/post_price_equation.php\" rel=\"nofollow noreferrer\">webpage</a>.</p>\n<p>As requested I've sketched out a solution to the specific case above.</p>\n<p>A n... |
17,541 | <p>I'm planning to scale up a PCR reaction, and I'm wondering if filling the PCR tubes to the maximum volume of 200 ul would be a problem. It would mean a lot less pipetting as I would only need 1/4 of the tubes.</p>
<p>The typical protocols I've seen always use 50 ul for a PCR reaction, I'm wondering if there are any... | [
{
"answer_id": 17560,
"pm_score": 3,
"text": "<p>Here is a simple example using your data in which both terms of the Price equation are needed, since the value of the character for $z_2 $ changes in the second generation. I used your suggested change $z_2'=(9\\cdot 2 + 1\\cdot 3)/10 = 2.1$. </p>\n\n<p>T... | [
{
"answer_id": 17533,
"pm_score": 2,
"text": "<p>This is a nice numerical walk-through and explanation, see this <a href=\"http://www.tedpavlic.com/post_price_equation.php\" rel=\"nofollow noreferrer\">webpage</a>.</p>\n<p>As requested I've sketched out a solution to the specific case above.</p>\n<p>A n... |
17,565 | <p>I am a bit confused with the notion that "<strong>walking after meals helps you in digestion</strong> ", </p>
<p>Some say that it helps, whereas others oppose it. Can someone come up with a valid explanation for this?</p>
| [
{
"answer_id": 17566,
"pm_score": 4,
"text": "<p>apparently walking helps in the movement of food into the stomach and improves digestion. Also helps in decreasing blood sugar after meals, which decreases cardiovascular risk and potential signal diabetes by helping muscles absorb glucose in the blood. H... | [
{
"answer_id": 35432,
"pm_score": 2,
"text": "<p>Well it depends what you mean by helping digestion. </p>\n\n<p>This <a href=\"https://skeptics.stackexchange.com/posts/11169/edit\">answer</a> in skeptics may shade some light:</p>\n\n<blockquote>\n <p><b>a walk after my lunch [is] a healthy habit that h... |
17,568 | <p>To what extent do brains (e.g. of humans) contain <a href="http://en.wikipedia.org/wiki/Recurrent_neural_network">recurrent </a> connections? </p>
<p>I am studying artificial neuronal networks and frequently encountered the statement, that recurrent neural networks are closer to biological neuronal networks than fo... | [
{
"answer_id": 17569,
"pm_score": 4,
"text": "<p>The recurrent patterns of connections in a network are known as network motifs.</p>\n\n<p>You can check <a href=\"http://www.sciencemag.org/content/298/5594/824.full\">this</a> paper out. They have identified common network motifs in different types of re... | [
{
"answer_id": 20766,
"pm_score": 2,
"text": "<p>Ok, let's talk about mammalian neocortex rather than about the entire central nervous system.</p>\n\n<p>The vast majority of synapses within the cortex are formed between neurons within the same cortical area (<a href=\"http://dx.doi.org/10.1523/JNEUROSCI... |
17,591 | <p>If the squamous (top) layer of epidermis, or skin, is burned or damaged in another way, will it then be replaced by the next layer of below?</p>
<p>Also, from where does the basal membrane originate? Does it regenerate from a different layer of cells? </p>
| [
{
"answer_id": 17654,
"pm_score": 3,
"text": "<p>The epidermis is a four- or five-layered epithelium. The top layers are squamous whereas the bottom ones are more columnar (<a href=\"http://en.wikipedia.org/wiki/Epidermis_(skin)\" rel=\"nofollow noreferrer\">http://en.wikipedia.org/wiki/Epidermis_(skin)... | [
{
"answer_id": 17655,
"pm_score": 2,
"text": "<p>It would first be good to look at the <a href=\"http://www.webmd.com/skin-problems-and-treatments/picture-of-the-skin\" rel=\"nofollow noreferrer\">different layers within the skin </a> as you mentioned in your question. </p>\n\n<blockquote>\n <p>The sk... |
17,597 | <p>Quoting from : Scientific American July 1975 <em>The Manipulation of genes</em> by Stanley Cohen :</p>
<blockquote>
<p>Restriction endonucleases (and modification methylases) are widespread
in microorganisms; genes for <strong>making</strong> them were found on <strong>viral
chromosomes</strong> and extrachro... | [
{
"answer_id": 17654,
"pm_score": 3,
"text": "<p>The epidermis is a four- or five-layered epithelium. The top layers are squamous whereas the bottom ones are more columnar (<a href=\"http://en.wikipedia.org/wiki/Epidermis_(skin)\" rel=\"nofollow noreferrer\">http://en.wikipedia.org/wiki/Epidermis_(skin)... | [
{
"answer_id": 17655,
"pm_score": 2,
"text": "<p>It would first be good to look at the <a href=\"http://www.webmd.com/skin-problems-and-treatments/picture-of-the-skin\" rel=\"nofollow noreferrer\">different layers within the skin </a> as you mentioned in your question. </p>\n\n<blockquote>\n <p>The sk... |
17,599 | <p>I'd appreciate some help identifying these three corvids I photographed in Austria during the Summer:</p>
<p><a href="https://i.stack.imgur.com/AIyuO.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/AIyuO.jpg" alt="corvids"></a></p>
<p>I know identifying corvids can be difficult and I'm not an or... | [
{
"answer_id": 60503,
"pm_score": 4,
"text": "<h1>1. <strong>Carrion crow</strong> (<a href=\"https://en.wikipedia.org/wiki/Carrion_crow\" rel=\"noreferrer\"><em><strong>Corvus corone</strong></em></a>)</h1>\n<p><a href=\"https://i.stack.imgur.com/fl9tJm.jpg\" rel=\"noreferrer\"><img src=\"https://i.sta... | [
{
"answer_id": 21355,
"pm_score": 3,
"text": "<p>The first 2 are correct.\nThe third one is actually a hooded crow. The different color of the wing depends on the generation of feathers. Feathers of different generations (changed during different time) are abraded (used) in a different way. The wing fea... |
17,629 | <p>For maggot therapy, how are maggots disinfected? I'd imagine there's a limited scope of measurements that can be taken to sterilize the maggots - i.e. we don't want to sterilize them and kill them too. </p>
| [
{
"answer_id": 17793,
"pm_score": 5,
"text": "<p><strong>History</strong></p>\n<p><a href=\"http://en.wikipedia.org/wiki/Ambroise_Par%C3%A9\" rel=\"noreferrer\">Ambroise Paré</a> is credited with being the first to note his observations on <a href=\"http://en.wikipedia.org/wiki/Maggot_therapy\" rel=\"no... | [
{
"answer_id": 17792,
"pm_score": 3,
"text": "<p>There is an interesting and authoritative paper on rearing of larvae of blue bottle flies for debridement purposes, cited below. </p>\n\n<blockquote>\n <p>Essentially the eggs are disinfected (rinsed) using .25 % chloramine solution (NH2Cl), then the lar... |
17,631 | <p>I have been wondering why would insects in general, not be scared when important changes happen on your monitor where they have landed...</p>
<p>If you move even just a finger, they are <em>scared to death</em> and fly away, but anything on my monitor and they remain completely placid.</p>
| [
{
"answer_id": 28251,
"pm_score": 5,
"text": "<p>Flies see motion. When the monitor screen changes, the visible spectrum of the pixel is changing and nothing is moving.</p>\n\n<blockquote>\n <p>Flies have limited color vision. Each color has its own wave frequency, but flies have only two kinds of colo... | [
{
"answer_id": 50671,
"pm_score": 1,
"text": "<p>Flies monitor the space above them:</p>\n\n<p>Flies have a very strong innervation of the back of the head, which contacts the surface ( <a href=\"http://flybase.org/reports/FBim0000875.html\" rel=\"nofollow\">http://flybase.org/reports/FBim0000875.html</... |
17,741 | <p>Wikipedia says Caliciviridae Family.
My notes say that Norovirus includes the following</p>
<p>Noroviruses</p>
<ul>
<li>Norwalk-like viruses</li>
<li>Caliciviruses</li>
<li>Astroviruses and some small gastroenteroviruses</li>
</ul>
<p>which is a larger definition including at least two families than the Wikipedia... | [
{
"answer_id": 17744,
"pm_score": 4,
"text": "<p>You are mixing different things here: Virus are grouped based on their genetic material (dsDNA, ssDNA ssRNA and so on) into several groups (see <a href=\"http://en.wikipedia.org/wiki/Virus_classification\">here</a> for details), then grouped into families... | [
{
"answer_id": 17752,
"pm_score": 1,
"text": "<p>I take <a href=\"http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi\" rel=\"nofollow\">NCBI's taxonomy</a> any day over what wikipedia says. According to NCBI Caliciviridae includes Lagovirus, Nebovirus, Norovirus, Recovirus, Sapovirus, Vesivirus, Se... |
17,742 | <p>Digesting (trypsin or whatever other proteolytic enzyme) proteins generates multiple peptides so the degree of complexity of the sample, at the peptide level, increases a lot. In addition there is the problem of infering the original protein from its constituent peptides.
Why is this digestion step needed when you... | [
{
"answer_id": 19139,
"pm_score": 1,
"text": "<p>I found the answer to my own question\nIt was formulated in a Nature publication by Mathias Mann (Title: The ABC's (and XYZ's) of peptide sequencing), a pope in Proteomics:</p>\n<blockquote>\n<p>Why are peptides, and not proteins, sequenced?</p>\n<p>After... | [
{
"answer_id": 17743,
"pm_score": 2,
"text": "<p>This is going to be a very long answer but to give a short response.</p>\n\n<p>You have to consider that MS for peptide detection works on the bases/principle of mass to charge (m/z) to detect an AA molecule, which is then normalised and analysed etc etc ... |
17,799 | <p><strong>Background</strong></p>
<p>The standard definition of species refers to the concept of <a href="http://simple.wikipedia.org/wiki/Reproductive_isolation" rel="nofollow noreferrer">reproductive isolation</a>. If two lineages are found to be reproductively isolated, then we consider these two lineages to belon... | [
{
"answer_id": 17801,
"pm_score": 5,
"text": "<p>Rice and Salt$^1$ bred fruit flies for 35 generations and from one line of flies created two groups that were isolated from each other reproductively. They could not interbreed because they no longer bred in the same environment. Depending on one's defini... | [
{
"answer_id": 17819,
"pm_score": 3,
"text": "<p>Diane Dodd's experiments on Drosophila pseudoobscura would be another example of lab-based speciation. </p>\n\n<p><a href=\"http://www.jstor.org/stable/2409365?__redirected\" rel=\"noreferrer\">http://www.jstor.org/stable/2409365?__redirected</a></p>\n\n<... |
17,823 | <p>I read about this <a href="http://www.instructables.com/id/Mosquito-trap-mosquito-abortion-clinic-or-source-t/">idea for a mosquito trap</a> (with a rather tactless name) where the idea seems to be that because the water available for the mosquito eggs is so shallow, they will die somehow or not be viable. Mosquitos... | [
{
"answer_id": 17824,
"pm_score": 4,
"text": "<p>Many mosquitoes, such as Culex quinquefasciatus, lay their eggs on the surface of fresh or stagnant water. The water may be in tin cans, barrels, horse troughs, ornamental ponds, swimming pools, puddles, creeks, ditches, catch basins or marshy areas. Mosq... | [
{
"answer_id": 77062,
"pm_score": 0,
"text": "<p>I have them in my property breeding in my containers all the time. From a few inches gets the best results (more mosquitoes) but I’ve gotten colonies in water up to 2-3’ deep. </p>\n"
}
] |
17,840 | <p>In the resting membrane potential of neurons the inside of membrane is kept negative and outside of membrane is kept positive by the utilization of energy through Na-K Atpase pump, While during action membrane potential through the opening of specific gated ion channels inside of membrane is made positive while outs... | [
{
"answer_id": 17824,
"pm_score": 4,
"text": "<p>Many mosquitoes, such as Culex quinquefasciatus, lay their eggs on the surface of fresh or stagnant water. The water may be in tin cans, barrels, horse troughs, ornamental ponds, swimming pools, puddles, creeks, ditches, catch basins or marshy areas. Mosq... | [
{
"answer_id": 77062,
"pm_score": 0,
"text": "<p>I have them in my property breeding in my containers all the time. From a few inches gets the best results (more mosquitoes) but I’ve gotten colonies in water up to 2-3’ deep. </p>\n"
}
] |
17,845 | <p>There are many combination vaccines available but I've noticed that there don't seem to be any with both live and non-live components, e.g. DTaP/IPV/MMR. Such combinations could be useful in some cases, since most developed countries give a second dose of MMR (or MMRV) at the same time as DTaP/IPV. Is there a biolog... | [
{
"answer_id": 20110,
"pm_score": 4,
"text": "<p>First let me point out that for the US, I'm not knowledgeable enough to speak for the rest of the world, you are correct.</p>\n\n<hr>\n\n<p><strong>There are no approved live attenuated vaccines mixed with componet/subunit/inactivated vaccines.</strong></... | [
{
"answer_id": 20059,
"pm_score": 3,
"text": "<p>The major reason for this are differences in the preparation methods. <a href=\"http://en.wikipedia.org/wiki/Attenuated_vaccine\">Live (attenuated) vaccines</a> need permanent cooling, which makes their use in third world countries difficult. </p>\n\n<p><... |
17,899 | <p>Some <em>Aspergillus</em> species appear to like walnuts. My question concerns the association of <em>Penicillium</em> and <em>Aspergillus</em>. No sooner does <em>Aspergillus</em> colonize a walnut (or some other challenging carbon source) than <em>Penicillium</em> seems to move in, eventually killing the <em>Asper... | [
{
"answer_id": 17901,
"pm_score": 4,
"text": "<p>It is hard to find any articles on the <em>association</em> between <em>Penicillium</em> and <em>Aspergillus</em> species, although they are both considered <a href=\"http://www.jiaci.org/issues/vol18issue3/2.pdf\" rel=\"noreferrer\">two of the most commo... | [
{
"answer_id": 40652,
"pm_score": 2,
"text": "<p>A year after the fact I found a short passage in Thom and Raper's 1945 text, <em>Manual of the Aspergilli.</em> At page 59 the authors relate that <em>Aspergillus niger</em> colonies are commonly overrun with <em>Penicillium rugulosum</em> which \"winds i... |
17,902 | <p>Some peppers, such as the <a href="https://en.wikipedia.org/wiki/Habanero_chili">habanero</a> or <a href="https://en.wikipedia.org/wiki/Carolina_Reaper">Carolina reaper</a> are extremely spicy, and when eaten in larger amounts than one is accustomed to, can cause some discomfort.</p>
<p>I've also heard anecdotes cl... | [
{
"answer_id": 17903,
"pm_score": 5,
"text": "<p>The more "dangerous" properties of spicy peppers are chiefly due to capsaicin.</p>\n<p>Sigma-Aldrich sells <a href=\"http://www.sigmaaldrich.com/catalog/product/sigma/m2028?lang=en&region=US\" rel=\"noreferrer\">purified capsaicin</a>, for w... | [
{
"answer_id": 17910,
"pm_score": -1,
"text": "<p>If you have cardiovascular problems, then it should be quite possible for the pain cause by spicy peppers to trigger a heart attack via a spike in blood pressure. A similar scenario might occur with respiratory diseases. And of course an anaphylactic sho... |
17,924 | <p>I have a question about cancer cure statistics. Many of the cancer literature or databases I have come across speak about 5 year or 10 year survival rates. In this case survival means that the patient with cancer is still alive 5 or 10 years after diagnosis. I am in need of references about the statistics which expl... | [
{
"answer_id": 17903,
"pm_score": 5,
"text": "<p>The more "dangerous" properties of spicy peppers are chiefly due to capsaicin.</p>\n<p>Sigma-Aldrich sells <a href=\"http://www.sigmaaldrich.com/catalog/product/sigma/m2028?lang=en&region=US\" rel=\"noreferrer\">purified capsaicin</a>, for w... | [
{
"answer_id": 17910,
"pm_score": -1,
"text": "<p>If you have cardiovascular problems, then it should be quite possible for the pain cause by spicy peppers to trigger a heart attack via a spike in blood pressure. A similar scenario might occur with respiratory diseases. And of course an anaphylactic sho... |
17,926 | <p>I received a gift that is a jug of Pure Mexican Vanilla. Having never dealt with large quantities of vanilla, it made me curious as to what would happen if a person had too much vanilla.</p>
<p>I understand that the alcohol has a higher toxicity rate and is probably more fatal than the actual vanilla itself, but I'... | [
{
"answer_id": 17928,
"pm_score": 5,
"text": "<p>Vanillin is the chemical that gives vanilla its flavour and smell <sup>[1]</sup>.</p>\n\n<blockquote>\n <p>Vanillin is pharmacologically active, causing depressed blood pressure, increased respiratory rate & death due to cardiovascular collapse <sup>... | [
{
"answer_id": 17927,
"pm_score": 2,
"text": "<p>Out of interest, I've had a look around a bit and it seems like the most dangerous part of that bottle might be the alcohol.</p>\n\n<p>According to the <a href=\"http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=169.3\" rel=\"nofoll... |
17,980 | <p>In a documentary on fitness I saw it was stated that women can't get big like men because of their low concentration of testosterone. If it is true that women have testosterone, where is it made? Why do some women, especially later in life, develop facial hair (though obviously not as much as men)? Do men also have ... | [
{
"answer_id": 17981,
"pm_score": 5,
"text": "<p>Yes, they do. The ovaries produce both testosterone and estrogen. Relatively small quantities of testosterone are released into your bloodstream by the ovaries and adrenal glands. Sex hormones are involved in the growth, maintenance, and repair of reprodu... | [
{
"answer_id": 19328,
"pm_score": 1,
"text": "<p>Healthy young males have estradiol levels in the area of 20-30 pg/ml.\nAlso, estrogen is a group of hormones, including estradiol and estrone for example. You shouldn't think of any hormones as women hormones or men hormones really, as both genders have t... |
18,987 | <p>Guanidium salts like (G-isothiocyanate) disrupt the hydrophobic interactions inside a protein or nucleic acid and denature it. What happens when hydrophobic interactions in DNA are broken? (I don't think it should get ssDNA because guanidium doesn't break hydrogen bonds within molecules)</p>
| [
{
"answer_id": 18989,
"pm_score": 3,
"text": "<p>Guanidium is a chaotrope i.e it increases the entropy in the solution. It doesn't <em>disrupt</em> hydrophobic interactions. Guanidium and urea act by forming hydrogen bonds. They can bond with both the dissolved macromolecule and water. The water molecul... | [
{
"answer_id": 18990,
"pm_score": 2,
"text": "<p>It is important to realize that the hydrophobic effect is largely due to the exclusion of water from non-polar surfaces, which increases entropy. This effect is a major contributor to the helical structure of DNA, which effectively brings the bases closer... |
19,002 | <p>Is there any academic reference that shows α-tubulin is around 50-55 kDa? The only thing I found is some data sheets from companies. I need the real reference.</p>
| [
{
"answer_id": 19003,
"pm_score": 3,
"text": "<p>The paper titled <a href=\"http://jcs.biologists.org/content/119/5/858.full\" rel=\"nofollow\">Identification of α-tubulin as a granzyme B substrate during CTL-mediated apoptosis</a> mentions it as 51KDa and the paper titled <a href=\"http://www.nature.co... | [
{
"answer_id": 19004,
"pm_score": 2,
"text": "<p>This is not so easy to answer, since alpha-tubulin has at 10 known genes in this family (data from <a href=\"http://www.ensembl.org/Homo_sapiens/Gene/Family/Genes?cdb=compara;db=core;family=ENSFM00250000000217;g=ENSG00000167552;r=12:49578579-49583107\" re... |
19,013 | <p>Why are some neurons tetraploid, and how does this result from it's ancestor cell ?</p>
| [
{
"answer_id": 19015,
"pm_score": 3,
"text": "<p>Neurons are tetraploid in pathological situations like Alzheimer disease:</p>\n<blockquote>\n<p>Neurons that duplicate their DNA are rarely observed to undergo mitosis, and they remain for long time as tetraploid cells, in accordance with the chronic cour... | [
{
"answer_id": 73131,
"pm_score": 0,
"text": "<p>It's not all pathological. From the same second article cited:</p>\n\n<blockquote>\n <p>Modern techniques such as flow cytometry, fluorescent in situ\n hybridization (FISH), slide-based cytometry (SBC) and quantitative PCR\n analysis of DNA from isolat... |
19,020 | <p>I have been reading about Maltose Binding Proteins. Mutant forms of the molecule seem to be named MalE_ where the _ represents a number, for example MalE36 or MalE50.</p>
<p>Please can someone explain the naming convention for this? i.e. what does the 'E' stand for? Does the number refer to the amino acid that has ... | [
{
"answer_id": 19015,
"pm_score": 3,
"text": "<p>Neurons are tetraploid in pathological situations like Alzheimer disease:</p>\n<blockquote>\n<p>Neurons that duplicate their DNA are rarely observed to undergo mitosis, and they remain for long time as tetraploid cells, in accordance with the chronic cour... | [
{
"answer_id": 73131,
"pm_score": 0,
"text": "<p>It's not all pathological. From the same second article cited:</p>\n\n<blockquote>\n <p>Modern techniques such as flow cytometry, fluorescent in situ\n hybridization (FISH), slide-based cytometry (SBC) and quantitative PCR\n analysis of DNA from isolat... |
19,051 | <p><a href="https://en.wikipedia.org/wiki/Botulinum_toxin" rel="nofollow noreferrer">Botulinum toxin</a> is the neurotoxin protein created when botulism spores grow. The requirements for growth and/or for keeping the toxin from denaturing would seem to be very difficult to create in bale of hay.</p>
<p>There are well ... | [
{
"answer_id": 19130,
"pm_score": 4,
"text": "<p>As an addendum to Spinorial's answer, and after some research, the Center for Food Security and Public Health <em>specifically</em> lists hay / grass / <strong>decaying vegetable matter</strong> as a potential source for <em>C. botulinum</em> growth in th... | [
{
"answer_id": 19129,
"pm_score": 3,
"text": "<p>Clostridium botulinum toxin is present ubiquitously in soil. As such it is more than plausible that hay bails, which come into contact with soil can and I should expect almost probably will be infected with these bacteria. However it is not the mere prese... |
19,081 | <p>It is a cliche of freshman biology labs to point out that "every cycle of PCR doubles the DNA, so the yield will be $2^{cycles}$ times the template amount". However, if this were true, 1 ng of template would generate about 35 billion ng after 35 cycles, or 35 <em>grams</em> of DNA. This is clearly absurd and not the... | [
{
"answer_id": 42267,
"pm_score": 4,
"text": "<p><strong>An expected efficiency for a typical PCR is 80%, meaning each cycle multiplies the copy number of the targeted DNA sequence 1.58 times.</strong></p>\n\n<p>Firstly, it makes more sense to refer to the amount of DNA in a polymerase chain reaction in... | [
{
"answer_id": 19094,
"pm_score": 1,
"text": "<p>The equation is correct, but there's an additional asymptotic limit to a maximum concentration of product depending on the starting concentration of NTPs, template and primer pairs in solution too. </p>\n"
}
] |
19,095 | <p>For example, what's a $dt^{sz}$ hamster? (<a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1144494/" rel="nofollow">http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1144494/</a>). </p>
<p>What's a Rgs9-Cre/+;gtROSA/+ mouse? (<a href="http://www.sciencedirect.com/science/article/pii/S2212877813000719" rel="nofollow">... | [
{
"answer_id": 19097,
"pm_score": 4,
"text": "<p>Those describe the genotype of an animal (or plant, virus etc.).</p>\n\n<p>The nomenclature can be very varied and domain-specific, but for those two examples:</p>\n\n<p>$dt^{sz}$ is a Syrian golden hamster model with a spontaneous mutation (i.e. occurred... | [
{
"answer_id": 19096,
"pm_score": 3,
"text": "<p>These strings are specific genotypes of these animals. They often denominate mutations or transgenes. \nFor the hamster $dt^{sz}$ stands for dystopic, the sz comes from the first denomination of this symptoms as seizure. See <a href=\"http://books.google.... |
19,115 | <p>Why isn't DNA like RNA; why isn't RNA like DNA, that is, helical? Why are RNA chains straight?</p>
| [
{
"answer_id": 19118,
"pm_score": 4,
"text": "<p>The helix shape of DNA molecule is a consequence of its secondary structure. This refers to the bases contained in the molecule which pair, thus determining tertiary structure [1].</p>\n<p>Basepairing also occurs in RNA, so it can form a double helix. In ... | [
{
"answer_id": 19119,
"pm_score": 3,
"text": "<p>RNA (single or double stranded) actually can and does form a helix in the absence of certain complex 3D structures. The RNA helix is typically A-form, as opposed to B-form for typical DNA. The A-form helix is right-handed like the B-form but is more compa... |
19,162 | <p>Once, as a child, I found a spider in my parents' garden. I remember catching it in a jar because I thought it looked unusual, but I never figured out what kind of spider it was and unfortunately didn't get any pictures. I've been looking for it in books and on the Internet since, based on memory, with no luck.</p>
... | [
{
"answer_id": 19698,
"pm_score": 3,
"text": "<p>This may be what you are searching for:</p>\n\n<p><img src=\"https://i.stack.imgur.com/dDlkk.jpg\" alt=\"enter image description here\"></p>\n\n<p>It's actually a <strong>male purseweb spider</strong> (Atypus affinis), the color fades to black, eventually... | [
{
"answer_id": 97043,
"pm_score": 0,
"text": "<p>Was it this? This is another purseweb spider species.</p>\n<p><a href=\"https://i.stack.imgur.com/r9Gtv.jpg\" rel=\"nofollow noreferrer\"><img src=\"https://i.stack.imgur.com/r9Gtv.jpg\" alt=\"enter image description here\" /></a></p>\n"
}
] |
19,204 | <p>Say you have a needle, and you poke a very specific area on your left thumb.
A signal gets sent from that nerve up your spine and into your brain.</p>
<p>How does the brain know exactly where this signal has come from to such accuracy?</p>
<ul>
<li>Does each nerve in every conceivable part of the body have a uniqu... | [
{
"answer_id": 19209,
"pm_score": 3,
"text": "<p>In addition to what Spinoral has said, and in response to your comment above, I will add a bit more about the mechanisms.</p>\n\n<p>Essentially, in some form or another it's receptive fields all the way up.</p>\n\n<p>A brief outline of the anatomy:\nThe c... | [
{
"answer_id": 19206,
"pm_score": 3,
"text": "<p>The accuracy of sensation is actually quite variable depending on the region of our body. Highly innervated areas such as our fingers have a higher degree of accuracy than sparsely innervated areas such as our legs.</p>\n\n<p>There is a simple experiment ... |
19,210 | <p><strong>Background:</strong> I'm currently performing research in mathematical biology,
specifically on the treatment dynamics of HIV and TB co-infection.</p>
<p><strong>Question:</strong> Can a person infected with TB disease, who are undergoing treatment for it, infect a person with no history of TB bacteria in ... | [
{
"answer_id": 19211,
"pm_score": 4,
"text": "<p>First there is one major difference between HIV and TB: As long as the TB bacteria are still susceptible to treatment (which is developing into a major problem in some regions of the world) there is a effective treatment which can eradicate the infection.... | [
{
"answer_id": 19217,
"pm_score": 2,
"text": "<p>I think its a bit difficult to compare HIV and TB this way because TB is transmitted mainly through respiratory droplets whilst HIV is mainly through contamination of blood products/sex, etc but not via the respiratory route. As far as I know, there's sti... |
19,303 | <p>I bought a blood pressure monitor (A&D UA-851) which has the option to measure irregular heartbeat. I do understand what 'irregular' means, but why do irregular heartbeats happen and what are it's implications short and long term? </p>
| [
{
"answer_id": 19306,
"pm_score": 5,
"text": "<p>The normal cardiac cycle is comprised of two distinct phases: <strong>the systolic phase</strong> in which the heart contracts, ejecting the blood, followed by the <strong>the diastolic phase</strong> when the cardiac muscle relaxes, refilling the heart w... | [
{
"answer_id": 27472,
"pm_score": 3,
"text": "<p>Very simply putting, irregular heat beat means that the pulse is not regular. It can be diagnosed by checking your pulse clinically. </p>\n\n<p>Irregularities are further classified as: </p>\n\n<ol>\n<li><p>Regularly Irregular: this occurs in heart blocks... |
19,310 | <p>Not all carcinogens are mutagens. Alcohol and estrogen, for example, does not damage DNA.</p>
<p>It's one of the assumptions of the Ames test that mutagenicity implies carcinogenicity, but is this <em>always</em> the case? I assumed that it was, but then I <a href="https://biology.stackexchange.com/questions/14399/... | [
{
"answer_id": 19331,
"pm_score": 5,
"text": "<h3>Short answer</h3>\n<p>All mutagens are potential carcinogens unless the mutagen is highly specific to a site. As noted in the question, carcinogens need not be mutagenic.</p>\n<hr />\n<p>HPV causes oncogenic transformation of a cell because of certain pr... | [
{
"answer_id": 19311,
"pm_score": 1,
"text": "<p>I'm no expert on the matter, but just quoting from <a href=\"http://en.wikipedia.org/wiki/Mutagen\" rel=\"nofollow noreferrer\">Wikipedia</a>:</p>\n<blockquote>\n<p>Mutagens are not necessarily carcinogens, and vice versa. Sodium Azide for example may be ... |
19,312 | <p>I am not comparing a cat with leopard.</p>
<p>I am just saying that we humans are all one type of creature and we are diverse (I am not saying we are class of mammals and phylum of etc and kingdom etc, because my religion doesn't believe in it).</p>
<p>So consider the class of cats they are one type of species so ... | [
{
"answer_id": 19313,
"pm_score": 5,
"text": "<p>In your question, your assumption that animal species are less diverse phenotypically than humans is wrong. I am sure you will appreciate @terdon's answer to <a href=\"https://biology.stackexchange.com/questions/14414/do-humans-have-enough-biological-diff... | [
{
"answer_id": 19315,
"pm_score": 3,
"text": "<p>I'd like to add that the variations in individuals within a species are a fundamental observation upon which modern biology is standing. Darwin wrote at least <a href=\"http://www.markhannam.com/essays/essay5a.htm\" rel=\"nofollow noreferrer\">2 chapters... |
19,381 | <p>I visited a bird enclosure close to where I live in Australia. The enclosure had several different species. The birds that stood out most were these doves sitting right along the fence railing, making a deep "Wo-wo-wo-woo" sound. That and also I thought they looked and sounded similar to Spotted Doves.</p>
<p><img ... | [
{
"answer_id": 19382,
"pm_score": 3,
"text": "<p>I think this is a Barbary dove (or Ringneck dove). See this image (from the <a href=\"http://nzbirdsonline.org.nz/species/barbary-dove\" rel=\"nofollow noreferrer\">here</a>):</p>\n\n<p><img src=\"https://i.stack.imgur.com/dFbDY.jpg\" alt=\"enter image de... | [
{
"answer_id": 19383,
"pm_score": 1,
"text": "<p>it is symi bird and more over it is commonly called as collared dove its a resident of symi and would have brought to australia by other means\n<img src=\"https://i.stack.imgur.com/dX223.jpg\" alt=\"enter image description here\">\nyou can find a list off... |
19,411 | <p>I got this doubt when I was studying about <a href="http://en.wikipedia.org/wiki/Hematocrit" rel="nofollow">haematocrit</a> value. According to my NCERT textbook males have greater number of RBCs than females. But who will have more RBCs when comparing a normal male and a female who lives at a higher altitude?</p>
... | [
{
"answer_id": 19413,
"pm_score": 3,
"text": "<p>Currently impossible to give a definite answer... It depends what altitude you look at. </p>\n\n<p>Going from @Alan_boyd's answer the normal range is 40-50% for males and 36-44% for females. If the altitude at which a person is acclimatized to correlates ... | [
{
"answer_id": 19412,
"pm_score": 2,
"text": "<p>According to the <a href=\"http://www.nlm.nih.gov/medlineplus/ency/article/003646.htm\" rel=\"nofollow\">MedlinePlus site</a> these are the normal ranges for haematocrit:</p>\n\n<p>Male: 40.7 - 50.3%</p>\n\n<p>Female: 36.1 - 44.3%</p>\n\n<p>Unfortunately ... |
19,416 | <p>FRET only works for interactions between 1nm to 20nm.</p>
<p>How can you be sure that the interaction that you want to study isn't less than 1 nm/greater than 20nm apart?</p>
| [
{
"answer_id": 19413,
"pm_score": 3,
"text": "<p>Currently impossible to give a definite answer... It depends what altitude you look at. </p>\n\n<p>Going from @Alan_boyd's answer the normal range is 40-50% for males and 36-44% for females. If the altitude at which a person is acclimatized to correlates ... | [
{
"answer_id": 19412,
"pm_score": 2,
"text": "<p>According to the <a href=\"http://www.nlm.nih.gov/medlineplus/ency/article/003646.htm\" rel=\"nofollow\">MedlinePlus site</a> these are the normal ranges for haematocrit:</p>\n\n<p>Male: 40.7 - 50.3%</p>\n\n<p>Female: 36.1 - 44.3%</p>\n\n<p>Unfortunately ... |
19,442 | <p>I am impressed by the illustrations for the Protein Data Bank ‘Molecule of the month’, e.g. the gorgeous image of <a href="http://www.rcsb.org/pdb/101/motm.do?momID=168" rel="nofollow noreferrer">DNA Helicase</a> below. Does anyone know how they were made or how one might create something similar?</p>
<p><a href="ht... | [
{
"answer_id": 19447,
"pm_score": 4,
"text": "<p>Those (really cool) pictures are created by David Goodsell using custom-written software.</p>\n<p>From an <a href=\"http://www.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/about.html\" rel=\"noreferrer\">interview to the artist</a>:... | [
{
"answer_id": 81545,
"pm_score": 2,
"text": "<p>I don’t actually consider these pictures either “gorgeous” or “cool” — they are not to my taste — and I’m not really sure that the question is about biology, but as it has resurfaced after almost 5 years I thought I’d give an answer which explained how on... |
19,455 | <p>I have a list of gene name in a file </p>
<pre><code>CHRNB2
EGR2
GCK
KRT14
LMNA
FGF3
TK2
ABCC8
</code></pre>
<p>How can I map them to uniprot ID ? <br>
<strong>P.S</strong> I tried Uniprot "ID mapping" (from-"GENEID" to-"UNIPROTKB AC"), but it couldn't map.<br>
Please suggest me what to do.</p>
| [
{
"answer_id": 19471,
"pm_score": 1,
"text": "<p>for biomart goto below link<br>\n<a href=\"http://central.biomart.org/converter/#!/ID_converter/gene_ensembl_config_2\" rel=\"nofollow\">http://central.biomart.org/converter/#!/ID_converter/gene_ensembl_config_2</a></p>\n\n<p>Also there is one more conver... | [
{
"answer_id": 48427,
"pm_score": 2,
"text": "<h1>ID mapping</h1>\n<p>This is called ID mapping. It used to be a headache as programmatic access was the only real way, but it is pretty trivial these days.</p>\n<p>As mentioned in the comments, by far the most popular and easy method is to use <strong>Uni... |
19,472 | <p>Last night I laid on my bed and tried to go to sleep with the light off.
I closed my eyes (but hadn't gone to sleep). My younger brother touched the wireless mouse (which had laser) for the laptop. He wiggled the mouse and it's laser contacted my closed eye . I knew some light was thrown on my face, and it's color ... | [
{
"answer_id": 19474,
"pm_score": 5,
"text": "<p>There are two reasons for light to appear red through the eyelids.</p>\n\n<ol>\n<li><p>Eyelids get a rich supply of blood which contains iron (in hemoglobin). The iron in blood absorbs all colors of light but reflects red light. (<a href=\"http://www.chem... | [
{
"answer_id": 19473,
"pm_score": 5,
"text": "<p>Short answer, your eyelids does not block all light. Since they are only a thin layer of skin, the light is able to pass through although not completely obviously. Since the eyes are still completely functional when you close them, only covered by the eye... |
19,495 | <p>How does a woodpecker go about smacking it's head into a tree without killing itself?</p>
| [
{
"answer_id": 19496,
"pm_score": 5,
"text": "<p>Various features of brain,skull and beak anatomy help to achieve protection.</p>\n<p>A paper was published in PLoSOne in 2011 on this very topic:</p>\n<p><a href=\"http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0026490\" rel=\"noreferr... | [
{
"answer_id": 19497,
"pm_score": 3,
"text": "<p>Gibson (2006) identified three characteristics that help woodpeckers avoid brain injury:</p>\n<blockquote>\n<p>their small size, which reduces the stress on the brain for a given acceleration</p>\n<p>the short duration of the impact, which increases the t... |
19,508 | <p>I have observed that frequently when people are hungry; they tend to get angry more easily on pointless issues. Does this mean that our fight or flight response is more active when a person is hungry? What is a possible reason for this? Is this phenomenon linked with our cell signaling pathways? If it is, then what ... | [
{
"answer_id": 19511,
"pm_score": 4,
"text": "<p>Brain's main energy source is glucose. It uses about 20% of total glucose [1]. Brain hypoglycemia causes depressive-like behaviors in mice through adrenergic pathways [2].</p>\n<p>When it comes to humans, here is a study that claims low glucose leads to i... | [
{
"answer_id": 19615,
"pm_score": 2,
"text": "<p><em>This is a short review about the issue and not complete.\nThis and the earlier answer are not proofs of the link between the two proceses.</em></p>\n\n<p>To investigate this better, I think it would be much easier first to narrow the case to </p>\n\n<... |
19,514 | <p>It is said that the stonefish (Synanceia) is able to stay out of the water for up to 24 hours. I wonder how they get oxygen from the air. Could someone explain this?</p>
| [
{
"answer_id": 19511,
"pm_score": 4,
"text": "<p>Brain's main energy source is glucose. It uses about 20% of total glucose [1]. Brain hypoglycemia causes depressive-like behaviors in mice through adrenergic pathways [2].</p>\n<p>When it comes to humans, here is a study that claims low glucose leads to i... | [
{
"answer_id": 19615,
"pm_score": 2,
"text": "<p><em>This is a short review about the issue and not complete.\nThis and the earlier answer are not proofs of the link between the two proceses.</em></p>\n\n<p>To investigate this better, I think it would be much easier first to narrow the case to </p>\n\n<... |
19,515 | <p>A steroid, testosterone was injected in female body which led to development of secondary sexual characters but these characters were not developed over night (Response was very slow). What could be possible explanation of this phenomenon</p>
<ol>
<li>a Steroid hormones produce a slow response because they do not h... | [
{
"answer_id": 19511,
"pm_score": 4,
"text": "<p>Brain's main energy source is glucose. It uses about 20% of total glucose [1]. Brain hypoglycemia causes depressive-like behaviors in mice through adrenergic pathways [2].</p>\n<p>When it comes to humans, here is a study that claims low glucose leads to i... | [
{
"answer_id": 19615,
"pm_score": 2,
"text": "<p><em>This is a short review about the issue and not complete.\nThis and the earlier answer are not proofs of the link between the two proceses.</em></p>\n\n<p>To investigate this better, I think it would be much easier first to narrow the case to </p>\n\n<... |
19,540 | <p>does the order of genes within a chromosome matter? or is the main thing that the genes are there.</p>
<p>so for example, our DNA is very similar to that of apes not only by the genes themselves but also by the arrangement of those genes in the chromosomes.</p>
<p>is the order of this arrangement significant? Or i... | [
{
"answer_id": 19555,
"pm_score": 4,
"text": "<blockquote>\n <p>is the difference between humans and mice due primarily to the\n different order of the genes or to the slight differences in the genes\n themselves?</p>\n</blockquote>\n\n<p>The latter.</p>\n\n<blockquote>\n <p>This question was raised... | [
{
"answer_id": 19541,
"pm_score": 2,
"text": "<p>Ye, the order matters. This can be seen in chromosomal translocations which can cause cancer.\nA example for that would be the translocation of IRF4 which happens in a subtype of multiple myeloma. The translocation is permanently activating the transcript... |
19,545 | <p>What features make one plant able to withstand dry spells better than another with relatively similar structure? For instance, one of my <a href="http://en.wikipedia.org/wiki/Rudbeckia" rel="nofollow">Rudbeckias</a> is wilting from drought at the moment, and an <a href="http://en.wikipedia.org/wiki/Oenothera" rel="n... | [
{
"answer_id": 20092,
"pm_score": 3,
"text": "<p>The difference may be related to how the plants fix carbon. While all plants convert CO₂ and H₂O to glucose and oxygen, there are at least three pathways that are used to do it. The C3 pathway is older and less efficient than the CAM and C4 pathways. Many... | [
{
"answer_id": 19589,
"pm_score": -1,
"text": "<p>Plants in drier conditions usually have reduced surface area, thick waxy cuticle covering the epidermis, reduced number of stomata, and water storage tissues that presides in its roots and leaves.</p>\n\n<p>This means that even if the plants are similar,... |
19,548 | <p>It seems like being nearsighted for much of your life due to elongated eyes would make it easier in general to focus on near objects rather than far since the lens would not have to change much. Since in old age we lose the ability to focus close images due to a hardening of the lens over time, wouldn't having eyes ... | [
{
"answer_id": 19551,
"pm_score": 3,
"text": "<p>It is generally understood that we tend to become hyperopic as we age (<a href=\"http://www.journalofvision.org/content/8/4/29.short\" rel=\"nofollow\">reference</a>). As to whether this aids in decreasing myopia is stated as marginal in papers. One paper... | [
{
"answer_id": 24026,
"pm_score": 1,
"text": "<p>Let me see whether I can explain this quickly. The eye size is tightly regulated genetically. Babies don't have big eyes, they have exactly the same sized eyes like adults, only their head is smaller. Myopic eyes are larger than normal and hyperopic eyes ... |
19,575 | <p>I'm studying a TCGA dataset trying to find correlations between gene expression and clinical data which might shed light on some pathways. One column of the clinical data provides a list of chemotherapy drugs the patient received and I'm pretty sure there's a wealth of possibility in this column but I don't know any... | [
{
"answer_id": 19579,
"pm_score": 3,
"text": "<p>There's <a href=\"http://www.pharmgkb.org/\" rel=\"nofollow\">this database</a> of genetic/drug interactions, which I think is pretty much exactly what you're looking for. </p>\n\n<p>Probably your best approach is to classify your drugs into a couple diff... | [
{
"answer_id": 34644,
"pm_score": 1,
"text": "<p>Resonating provided a good general classification scheme that could be implemented for categorizing chemotherapeutic agents. Another resource that could be used is the following: <a href=\"http://www.genome.jp/kegg/drug/\" rel=\"nofollow\">http://www.geno... |
19,590 | <p>In <a href="http://www.simonsfoundation.org/quanta/20140710-hints-of-lifes-start-found-in-a-giant-virus/#comment-142465" rel="nofollow">this piece</a> about giant viruses and the origin of life, in the context of the move from RNA world to DNA world, virologist Valerian Dolja states:</p>
<blockquote>
<p>In order ... | [
{
"answer_id": 19579,
"pm_score": 3,
"text": "<p>There's <a href=\"http://www.pharmgkb.org/\" rel=\"nofollow\">this database</a> of genetic/drug interactions, which I think is pretty much exactly what you're looking for. </p>\n\n<p>Probably your best approach is to classify your drugs into a couple diff... | [
{
"answer_id": 34644,
"pm_score": 1,
"text": "<p>Resonating provided a good general classification scheme that could be implemented for categorizing chemotherapeutic agents. Another resource that could be used is the following: <a href=\"http://www.genome.jp/kegg/drug/\" rel=\"nofollow\">http://www.geno... |
19,593 | <p>why plants can only synthesize D-glucose why not L-glucose along with D glucose. I know it very well that plants have only enzymes which can synthesize D-glucose but Why not they have enzymes which can also manufacture L-glucose. So that we could have mixture of L and D glucose molecules? What is the significance of... | [
{
"answer_id": 19579,
"pm_score": 3,
"text": "<p>There's <a href=\"http://www.pharmgkb.org/\" rel=\"nofollow\">this database</a> of genetic/drug interactions, which I think is pretty much exactly what you're looking for. </p>\n\n<p>Probably your best approach is to classify your drugs into a couple diff... | [
{
"answer_id": 34644,
"pm_score": 1,
"text": "<p>Resonating provided a good general classification scheme that could be implemented for categorizing chemotherapeutic agents. Another resource that could be used is the following: <a href=\"http://www.genome.jp/kegg/drug/\" rel=\"nofollow\">http://www.geno... |
19,612 | <p>This plant was found growing in Germany. I have never seen it before, reverse Google image search did not help either. Can you help me identify what type of plant this is?</p>
<p><img src="https://i.stack.imgur.com/2YcJL.png" alt="Full view">
<img src="https://i.stack.imgur.com/MrjTJ.jpg" alt="Flower">
<img src="ht... | [
{
"answer_id": 19618,
"pm_score": 4,
"text": "<p>This looks like some species of <em>Phytolacca</em> to me.</p>\n\n<p>It's possibly <em>Phytolacca americana</em>, which is native to the US (in fact it's an enthusiastic 'volunteer' in my garden) but <a href=\"http://books.google.com/books?id=5vd_ZE7UDV8C... | [
{
"answer_id": 55311,
"pm_score": 1,
"text": "<p>It is <a href=\"https://fr.wikipedia.org/wiki/Phytolacca_acinosa\" rel=\"nofollow noreferrer\">Phytolacca acinosa</a> because the flowers grow upwards and the fruits are ribbed. <a href=\"https://en.wikipedia.org/wiki/Phytolacca_americana\" rel=\"nofollow... |
19,648 | <p>Is it possible for a device to measure how much air we breathe in and out over the entire day and at what rate? I think if we have access to this data we can compare it across people.</p>
| [
{
"answer_id": 19682,
"pm_score": 3,
"text": "<p>What you are looking for is a spirometer. There are different types of spirometers serving different purposes like the Incentive spirometer and the peak flow meter. I would suggest that you go through the <a href=\"http://en.wikipedia.org/wiki/Spirometer\... | [
{
"answer_id": 19684,
"pm_score": 1,
"text": "<p>Another possibility is <a href=\"http://www.serinth.gr/en/products/ergospirometers/portable-ergospirometers/cosmed-k4b2.html\" rel=\"nofollow\">K4 device</a> and <a href=\"http://www.cosmed.com/en/products/cardio-pulmonary-exercise-testing/k4-b2-mobile-cp... |
19,653 | <p>I recently watched the video <a href="https://www.youtube.com/watch?v=R3unPcJDbCc">This Is Not Yellow</a> explaining how red, green, and blue pixels can be used to create images of all other colors. Since yellow is created with red and green pixels, how is a person with red-green colorblindness (me, for instance) ab... | [
{
"answer_id": 96315,
"pm_score": 1,
"text": "<p>Below is a summary of the information found <a href=\"https://commandcenter.blogspot.com/2020/09/color-blindness-is-inaccurate-term.html\" rel=\"nofollow noreferrer\">here</a> and from how <a href=\"https://enchroma.com/pages/how-enchroma-glasses-work\" r... | [
{
"answer_id": 19661,
"pm_score": 2,
"text": "<p>Normal people see color due to the bellow mentioned combination of red, green and blue:</p>\n\n<p><img src=\"https://i.stack.imgur.com/l99xj.jpg\" alt=\"enter image description here\"></p>\n\n<p>But due to genetic factors, The graph Distorts:</p>\n\n<p><i... |
19,656 | <p>I'm aware that our earliest records of many major animal and plant phyla come from the Cambrian or Precambrian periods, and I'm also vaguely aware of some of the objections raised with general concept of phyla. With this in mind, I'm curious which of widely accepted biological phyla appeared most recently, and what ... | [
{
"answer_id": 19659,
"pm_score": 4,
"text": "<p>In my view, we simply don't have good enough data to answer this question. The fossil evidence is too sparse prior to the Cambrian and the evidence that we do have suggests that the phyla were already too separated. Meanwhile, the depth of time and the di... | [
{
"answer_id": 19657,
"pm_score": 2,
"text": "<p>As far as I know there is no phylum which appeared after the Cambrian. Every discussion beyond that is close to speculation, as the divergence estimates of different studies vary significantly. \nYou might want to look into one of the resources mentioned ... |
19,658 | <p>I'm a computer scientist who is starting to dabble with biology. My eventual goal is to model different kinds of cells with a computer program. As of right now, I'm just trying to take some smaller steps.</p>
<p>First, I downloaded a complete human genome from <a href="http://hgdownload.cse.ucsc.edu/downloads.html#... | [
{
"answer_id": 19662,
"pm_score": 5,
"text": "<p>No, your approach will not work, you are taking a very simplistic view of an extremely complex system. Some of the problems you are ignoring are:</p>\n<ul>\n<li><p>Genes (eukaryotic genes anyway) are <a href=\"https://en.wikipedia.org/wiki/RNA_splicing\" ... | [
{
"answer_id": 19664,
"pm_score": 2,
"text": "<p>Why bother predicting proteins badly from DNA sequence when you could have just as well downloaded the manually curated human proteome?</p>\n\n<p>As to your questions:</p>\n\n<ol>\n<li><p>Are you asking about human genomes or genomes in general? The vast ... |
19,668 | <p>Take for example the human and the chimpanzee, they are "closely related" species since they are "close" to each other in a phylogenetic tree. However, this terminology seems pretty informal, what would be the formal way to specify that two or more species are "closely related"?</p>
| [
{
"answer_id": 19673,
"pm_score": 3,
"text": "<p>Are you looking for something like \"<a href=\"http://en.wikipedia.org/wiki/Sister_group\" rel=\"nofollow\">sister lineage</a>\" (or \"sister taxon\" or \"sister group\")</p>\n\n<p>This term may be more specific than what you're looking for, and to use it... | [
{
"answer_id": 19672,
"pm_score": 2,
"text": "<p>As <a href=\"http://en.wikipedia.org/wiki/Genus\" rel=\"nofollow\">genus</a> comes above species I'd consider using this term for the species which are close genetically (\"these two species are from the same genus\"). Above genus comes family etc...</p>\... |
19,708 | <p>As steroid hormones can pass through the plasma membrane by simple diffusion because they are lipid derived hormones, it means that they are capable of passing through every cell of our body, BUT why are only specific cells responsive against steroid hormones?</p>
<p>For example, all of our body cells almost contai... | [
{
"answer_id": 20402,
"pm_score": 3,
"text": "<p>Unlike other types of hormones, steroid hormones do not have to bind to plasma membrane receptors. Instead, they can interact with intracellular receptors that are themselves transcription activators. Steroid hormones too hydrophobic to dissolve readily i... | [
{
"answer_id": 19709,
"pm_score": 3,
"text": "<p>The quick answer is that only certain cell types express the required <a href=\"http://en.wikipedia.org/wiki/Steroid_hormone_receptor\">steroid hormone receptors</a> that are necessary to induce signaling and gene regulation when bound to their target ste... |
19,725 | <p>In an animal cell, especially neuron and in particular its axon, while there is electrical resistance and capacitance mechanism in the cell, which play essential roles in the cable theory model of neuronal action potential transmission, is there a prominent self <a href="http://en.wikipedia.org/wiki/Self_inductance"... | [
{
"answer_id": 20252,
"pm_score": 4,
"text": "<p>What one thinks, no matter how intuitive it may appear is not particularly relevant in science. The inductance associated with a neural axon has been well documented since Cole (1966). Its role in the propagation of neural signals is developed extensive... | [
{
"answer_id": 78594,
"pm_score": 1,
"text": "<p>There surely is inductance in neurons. This inductance is introduced by two different mechanisms. \n1. The coil structure of myelin sheaths can introduce a real electrical inductance. The solid evidence for this is the opposite spiraling directions betwee... |
19,744 | <p><a href="https://cooking.stackexchange.com/a/45589/11251">An answer on another SE site</a> mentions that sugar "at a certain level acts as a preservative". I've always been taught that microorganisms eat sugar and expel acids, that is why sugary food are damaging to teeth. <strong>How is it that sugar acts as a pres... | [
{
"answer_id": 19748,
"pm_score": 4,
"text": "<p>Sugar in high concentrations acts osmotic. This means that the water available in the cells is drawn towards the high concentration of a solutant (sugar), like in the image below (this is demonstrated with a plant cell, but the principle is the same for b... | [
{
"answer_id": 43042,
"pm_score": 2,
"text": "<p>Sugar participate in food preservation only at high concentrations. When microbes are introduced to high sugar concentrated environment, water inside the microbial cell diffuses out to the high sugar concentrated solute due to the phenomenon called <stron... |
19,749 | <p>I have some protein-ligand complexed that I have been docking with some other software and just want to use Autodock to evaluate those complexes. So, basically I just want to use it as a scoring function to take a look at the energy components - I don't want to re-dock the ligands into the protein binding sites.
Fr... | [
{
"answer_id": 20001,
"pm_score": 3,
"text": "<p>Okay, I finally figured it out. Basically there are those following 6 steps:</p>\n\n<ol>\n<li>Preparing a protein</li>\n<li>Preparing a ligand</li>\n<li>Generating a grid parameter file</li>\n<li>Generating maps and grid data files</li>\n<li>Generating a ... | [
{
"answer_id": 19751,
"pm_score": 2,
"text": "<p>You can use Autodock Vina. It provides an option to calculate local score only.</p>\n\n<blockquote>\n <p>displaying the individual contributions to the intermolecular score, before weighting (these are shown with \"--score_only\")</p>\n</blockquote>\n\n<... |
19,809 | <p>Cooperativity in gene expression is an important feature of many regulatory networks. Described using the <a href="http://en.wikipedia.org/wiki/Hill_equation_(biochemistry)" rel="nofollow">Hill function</a>, the most common example is a transcription factor (TF) that when bound to its target regulatory site, increas... | [
{
"answer_id": 19825,
"pm_score": 3,
"text": "<p>Positive co-operativity without feedback from the downstream genes:</p>\n\n<p>I guess Polycomb/Trithorax complexes will fit this criterion nicely.</p>\n\n<p>Polycomb group (PcG) represses Hox and other differentiation related genes (such as neurogenin) wh... | [
{
"answer_id": 19815,
"pm_score": 2,
"text": "<p>Interesting question. I think I have two examples for you which might be interesting.\nThe first is the co-regulation of the microphthalmia-associated transcription factor (MITF) in pigmentation by SOX10 and PGC1a/b. See this paper:</p>\n\n<ul>\n<li><a hr... |
19,811 | <p>I have an ant queen in a jar. This is what she looks like:</p>
<p><img src="https://i.stack.imgur.com/jTC29.jpg" alt="black ant queen captured in jar"></p>
<p>Because I'm planning to start an artificial ant nest, I'd like to learn something about that specific species of ant. This particular queen is very common i... | [
{
"answer_id": 71876,
"pm_score": 2,
"text": "<p>This cannot be a Lasius queen, it is a Formica queen. Although one of the main characteristic is the shape of the first segment of the funicula which cannot be seen on this picture, the general aspect of this queen (elongated, with red legs, does not have... | [
{
"answer_id": 19826,
"pm_score": 2,
"text": "<p>As @skymnige said it is definitely <strong>Black garden ant (<em>Lasius niger</em>)</strong></p>\n\n<p><img src=\"https://upload.wikimedia.org/wikipedia/commons/4/4c/Lasius_Niger_wingless_queen.jpg\" alt=\"\"></p>\n"
}
] |
19,827 | <p>Can epistaxis or nosebleeds be a cause of death?</p>
<p><img src="https://i.stack.imgur.com/o3wRX.png" alt=""></p>
| [
{
"answer_id": 19831,
"pm_score": 5,
"text": "<p>Yes, it can, but it is extremely rare.</p>\n\n<blockquote>\n <p>... nosebleeds are rarely fatal, accounting for only 4 of the 2.4 million deaths in the U.S. in 1999 [1].</p>\n</blockquote>\n\n<p>The main issue is that epistaxis can be a sign of potential... | [
{
"answer_id": 19830,
"pm_score": 3,
"text": "<p>Any injury, that results in external bleeding can lead to death, since it is a breach in the body's defenses and an entry point for pathogens.</p>\n\n<p>Explanation:</p>\n\n<p>When you have nose bleeding the blood must be coming from somewhere. Usually fr... |
19,836 | <p>I am trying to convert a MOL2 file (includes partial charges and hydrogen atoms) into a PDBQT file for re-scoring in AutoDock Vina. However, both approaches that I tried don't keep the hydrogen atoms from the MOL2 file (the PDBQT file doesn't contain hydrogen atoms).</p>
<p>The command I used for OpenBabel is </p>
... | [
{
"answer_id": 19837,
"pm_score": 3,
"text": "<p>You saw my last <a href=\"https://biology.stackexchange.com/questions/19749/how-to-use-autodock-just-for-rescoring\">answer of your question</a>? you can do that easily, just use </p>\n\n<pre><code>prepare_ligand4.py -l my.mol2 -A \"hydrogens\"\n</code><... | [
{
"answer_id": 34897,
"pm_score": 0,
"text": "<p>In babel: </p>\n\n<pre><code>babel my.mol2 my.pdbqt -xh\n</code></pre>\n\n<p>-x states options for writing .pdbqt files\n-h says keep hydrogens</p>\n"
}
] |
19,891 | <p>There are approximately 20k protein-coding genes found in the human genome. This number is presumably very small when considering all the genomes found in the diverse microbes associated with the human body. </p>
<p>Is there an estimate for the total number of protein-coding genes found in human microbiome? </p>
| [
{
"answer_id": 19897,
"pm_score": 4,
"text": "<p>The Human Microbiome Project collected samples as shown in the image below from healthy volunteers:</p>\n\n<p><img src=\"https://i.stack.imgur.com/FMnKs.jpg\" alt=\"enter image description here\"></p>\n\n<p>They give an estimate of about 8 Million genes i... | [
{
"answer_id": 19894,
"pm_score": 2,
"text": "<h2>Human Microbiome Project</h2>\n\n<p>According to Published data on HMP website:</p>\n\n<ul>\n<li>The human microbiome consists of all the microorganisms that reside in or on the human body. </li>\n<li>They may cause illness but some are necessary for goo... |
19,942 | <p>The metabolic rate measures how much energy an organism <strong>expends</strong> over a unit of time. Its breakdown for the human body in terms of its functions is well documented : so much for the heart, for the brain, etc.</p>
<p>In West et al, 2002 I have found an estimate for the metabolic rate of a single cell... | [
{
"answer_id": 20031,
"pm_score": 4,
"text": "<p>I was musing on this and did some strange googling, and have some ballpark figures for a bunch of different organisms. It's far from a complete answer but it's at least a start, and all this won't fit in a comment.</p>\n\n<p>DNA replication, I assumed, w... | [
{
"answer_id": 20149,
"pm_score": 1,
"text": "<p>A significant amount of heat generated by the cell does not come from the hydrolysis of an NTP. ATP is generated by a H+ gradient in the mitochondria, and this gradient is created by mechanisms which rely only in part by ATP. Most of the energy stores in... |
19,967 | <p>Besides religious prohibition, there are several non-religious arguments against eating pork. A few of which are: </p>
<ol>
<li>Pigs and swine are so poisonous that you can hardly kill them with strychnine or other poisons. </li>
<li>Swine and pigs have over a dozen parasites within them, eg tapeworms, flukes, wo... | [
{
"answer_id": 19968,
"pm_score": 6,
"text": "<blockquote>\n<p>Pigs and swine are so poisonous that you can hardly kill them with strychnine or other poisons.</p>\n</blockquote>\n<p>This is a <em>non-sequitur</em>. An animal being poisonous does not imply that it resists to poison, nor the reverse is tr... | [
{
"answer_id": 19969,
"pm_score": 3,
"text": "<p>First: There is no biological reason to not eat pork. These bans (Jewish and Islamic) are based on religious rules, so this is more a cultural, not so much a biological answer.</p>\n\n<p>The reasoning that pork meat would deteriorate pretty fast in warm c... |
19,972 | <p>As a child I watched tiny fiddler crabs living in conical shells, and many years later I find that people study fossil turritellids. So now I wonder: how old are shells, typically, that you see on beaches? Do they wear out after a year of sand abrasion? 100 years, a million? Is it known? </p>
| [
{
"answer_id": 39960,
"pm_score": 4,
"text": "<p>Mollusk shells found on typical east coast (US) beaches can range from days old (the animal that made the shell died recently) to thousands of years old. Some shells in our state, North Carolina, have been dated as 40,000 years old. A high number of \"s... | [
{
"answer_id": 19981,
"pm_score": 2,
"text": "<p>Ages of shell as a piece can be checked or counted. </p>\n\n<p><img src=\"https://njsurfriderdrafts.files.wordpress.com/2012/03/seashells1.jpg\" alt=\"\"></p>\n\n<p>Procedure:</p>\n\n<p>1) Examine the shell's ridges with a magnifying glass.</p>\n\n<p>2) T... |
19,998 | <p>Which part of the brain is the first place (from top to bottom) where all 31 pairs of spinal nerves (on each side) meet? Or if they all start at one place - where is that?</p>
<p>Nominally, the beginning of the spinal cord is the medulla oblongata, but perhaps the spinal nerves or some sort of "root" of every nerve... | [
{
"answer_id": 21289,
"pm_score": 4,
"text": "<p>They don’t meet. </p>\n\n<p><strong>Some framework:</strong> </p>\n\n<ul>\n<li>Spinal nerves contain motor, sensory, and autonomic fibers. Each of these have different pathways. </li>\n<li>Spinal nerves don’t go to the brain. Rather, they synapse in the ... | [
{
"answer_id": 20296,
"pm_score": 0,
"text": "<p>I am not sure whether I grasped the gist of your question appropriately, but let me provide some clarifications. </p>\n\n<p>$\\text{Nerve}$ is simply a collection of axons. Therefore, all the spinal nerves are just bundles of assorted nerve axons. </p>\... |
20,002 | <p>Let's say I drink some Kefir Milk, what happens to the lactic acid in the Kefir Milk that has entered my digestive system?</p>
| [
{
"answer_id": 20012,
"pm_score": 4,
"text": "<p>First, there are two different isomers of the lactic acid, the L(+)- and the D(-)-form. Both differ in the position of the OH-group in the molecule:</p>\n\n<p><img src=\"https://i.stack.imgur.com/FdfH2.png\" alt=\"enter image description here\"></p>\n\n<p... | [
{
"answer_id": 20003,
"pm_score": 3,
"text": "<p>Lactic acid has been found to act as a fuel for the muscles. Refer to: <a href=\"http://www.nytimes.com/2006/05/16/health/nutrition/16run.html?_r=0\">http://www.nytimes.com/2006/05/16/health/nutrition/16run.html?_r=0</a></p>\n\n<blockquote>\n <p>Most at... |
20,006 | <p>I sometimes use <a href="http://www.ruralking.com/agristar-2-4-d-amine-1-gallon.html?utm_medium=cse&utm_source=google&CAWELAID=1624250989&CAGPSPN=pla&catargetid=520009190000031013&cadevice=c&gclid=CjwKEAjwxtKeBRDMzoeQmYn5uHcSJACGCF3Dhs22FITlehPhZgOacOeZU5_PbIz8W8iI4BOsuTyoPBoCeW7w_wcB" rel="n... | [
{
"answer_id": 20138,
"pm_score": 4,
"text": "<p>According to <a href=\"http://www.purdue.edu/newsroom/research/2011/111122MurphyTransporter.html\" rel=\"noreferrer\">this link</a> from Purdue, the seed of the answer is this:</p>\n\n<blockquote>\n <p>The herbicide is used to kill broadleaf weeds, which... | [
{
"answer_id": 88996,
"pm_score": -1,
"text": "<p>The specificity of 2,4 D may be due to either limited translocation or rapid degradation ,altered vascular anatomy or altered perception of auxin in monocot</p>\n"
}
] |
20,019 | <p><a href="https://i.stack.imgur.com/lZrzJ.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/lZrzJ.jpg" alt="enter image description here"></a></p>
<p>In the picture above (Source: <a href="http://ecx.images-amazon.com/images/I/71zKixilmEL._SL1500_.jpg" rel="nofollow noreferrer">Amazon.com</a>, Unite... | [
{
"answer_id": 20022,
"pm_score": 3,
"text": "<p>The imnstrument is shown here upside down. If it is turned around, it looks like this:</p>\n\n<p><img src=\"https://i.stack.imgur.com/cwWXG.jpg\" alt=\"enter image description here\"></p>\n\n<p>The glass disc are placed around the middle tube. The operati... | [
{
"answer_id": 58826,
"pm_score": 1,
"text": "<blockquote>\n <p>Also, are these still used in everyday biological research? Teached\n for students?</p>\n</blockquote>\n\n<p>It's a hand microtome allright. As Chris explained, these are used to section thin slices of plant tissue, to be examined using a... |
20,034 | <p><strong>Dry Humping</strong>, is:</p>
<blockquote>
<p>dry humping is the process of two people repeatedly moving up and down and back and forth on top of each other fully clothed( or missing various pieces, but the penis must not come in contact with the vagina with out some sort of fabric separating them ex: box... | [
{
"answer_id": 20036,
"pm_score": 5,
"text": "<p>If there has been an ejaculation by the male, and semen is present, there is a chance of getting pregnant. Period. Teens really need to know that.</p>\n<p>I think you may have your terms confused - semen is the overall fluid released during an ejaculation... | [
{
"answer_id": 43572,
"pm_score": -1,
"text": "<p>It is effectively impossible to get pregnant by <a href=\"http://beforeplay.org/2014/01/can-sperm-go-through-clothes-and-get-a-woman-pregnant/\" rel=\"nofollow\">dry-humping</a> because the conditions that would have to be met for sperm to pass through m... |
20,086 | <p>Can you please give me some advice for a book in (evolutionary) <a href="http://en.wikipedia.org/wiki/Conservation_genetics" rel="nofollow">conservation genetics</a> that offers an in-depth review of the mathematical formulations used in this field.</p>
<p>I read the book <a href="http://www.amazon.fr/Evolutionary-... | [
{
"answer_id": 20101,
"pm_score": 3,
"text": "<p>This book \"<a href=\"http://www.cambridge.org/se/academic/subjects/life-sciences/ecology-and-conservation/primer-conservation-genetics\" rel=\"nofollow\">A primer of conservation genetics</a>\" would suit quite well I think. In particular chapter five de... | [
{
"answer_id": 20115,
"pm_score": 2,
"text": "<p>If you're interested in learning about the mathematics of population genetics, <a href=\"http://onlinelibrary.wiley.com/book/10.1002/0470047356\" rel=\"nofollow\">Population Genetics and Microevolutionary Theory</a> by Alan Templeton is an absolutely amaz... |
20,129 | <p><strong>Very simple:</strong> Why (and how) is regenerated skin different from original ?</p>
<p>As we know we lose skin cells that becomes the dust in out homes and it always grows back to full thickness right ? So when I have a cut, I imagined it to heal provisionally with whatever possible and then after some ti... | [
{
"answer_id": 20210,
"pm_score": 4,
"text": "<p>Human skin is made up of three layers [1]:</p>\n\n<ol>\n<li>Epidermis; it contains no blood vessels; it has 5 cellular layers (starting from surface):\n\n<ul>\n<li><strong>stratum corneum</strong></li>\n<li>stratum lucidum</li>\n<li>stratum granulosum</li... | [
{
"answer_id": 20147,
"pm_score": 2,
"text": "<p>You're confusing an emergent system with a determined system. Your cells have programming which emerges as the form you see. You are using determinism to decide what your form should be. Determinism gives one reaction for every action. Biology is emergent... |
20,176 | <p>There are many plants and animals named for the naturalist Charles Darwin, such as Darwin's Frog <em>(Rhinoderma darwinii)</em>, but which were named by him? I'm finding it difficult to find such a list.</p>
| [
{
"answer_id": 20200,
"pm_score": 4,
"text": "<p>I've discovered that searching for <a href=\"http://eol.org/search?q=darwin&type%5B%5D=taxon_concept\" rel=\"nofollow\">Darwin on the Encyclopedia of Life</a> (EOL) appears to prioritise in its search results those species named by Darwin rather than ... | [
{
"answer_id": 20186,
"pm_score": 3,
"text": "<p>I don't know if these are his earliest descriptions but Darwin did describe several species of Planaria, such as <em>Planaria vaginuloides</em>, <em>P. oceania</em>, plus a new genus, <em>Diplanaria</em> in 1844.</p>\n\n<p><a href=\"http://darwin-online.o... |
20,215 | <p>I've been looking at some sequenced exomes and found an interesting point mutation that causes a Proline-to-Leucine amino acid change in the protein. This seems like it could have a big impact on the protein's functionality but before I go any further I want to explore whether or not the variant is a sequencing arti... | [
{
"answer_id": 20216,
"pm_score": 4,
"text": "<p>I don't know, whether the organism you are working with is diploid, but suspect it's an animal (or even a mammal), so the most parsimonious explanation would be that you have <a href=\"https://en.wikipedia.org/wiki/Zygosity#Homozygous\">homozygotes</a> an... | [
{
"answer_id": 20236,
"pm_score": 0,
"text": "<p>Also I don't know what kind of genetic input your given but if there is variation in origin ie some saliva some cheek skin then there could be a tissue based difference in the genome. </p>\n"
}
] |
20,217 | <p>I saw this pic while crawling online and it was a bit different for me to predict which worm is this. </p>
<p><img src="https://i.stack.imgur.com/grEvP.jpg" alt="enter image description here"></p>
<p><strong>Source:</strong> <a href="http://www.seafishingtackle4u.com/softbaits/ragworms-latex-lures/" rel="nofollow ... | [
{
"answer_id": 20219,
"pm_score": 2,
"text": "<p>As Cornelius correctly pointed out, it's not a living worm :)</p>\n\n<p>As to the question, what kind of worm they tried to imitate, I'd say, they had a <a href=\"https://www.google.com/search?channel=fs&q=nereidae&tbm=isch\" rel=\"nofollow\">nere... | [
{
"answer_id": 20218,
"pm_score": 2,
"text": "<p>If you would have read the text from the source of that image (which by the way you didn't mention, I did a Google Image search and edited your question to include it), you would have known that what is seen in the picture is not a living thing, it is a l... |
20,225 | <p>Haven't looked into this to very long, but an initial search didn't return anything. </p>
<p>HIV uses certain co-receptors to enter our cells. Could we flood the blood stream with specially designed proteins that mimic cell receptors, either locking the virus out of vulnerable cells, or even causing the virus to re... | [
{
"answer_id": 20231,
"pm_score": 4,
"text": "<p>Yes, that should be possible. And it is one of the ways antibodies work. It is already used as a treatment against <a href=\"http://en.wikipedia.org/wiki/Rabies#Treatment\">rabies</a>. There you get a dose of immunoglobulins directed against the rabies vi... | [
{
"answer_id": 64317,
"pm_score": 1,
"text": "<p>This approach actually works on almost anything, given enough proteins and nanoscale \"griefing\".</p>\n\n<p>There was an experiment a few years back where scientists wrapped normal cell membranes around polyurethane beads. The surface looks like a normal... |
20,264 | <p>According to my textbook, Davson-Danielli's model of a phospholipid bilayer sandwiched between two layers of globular protein was incorrect. The nonpolar protein portions would separate the polar portions of the phospholipids from water, causing the bilayer to dissolve. Meaning, the Davson-Danielli model is not only... | [
{
"answer_id": 20265,
"pm_score": 4,
"text": "<p>The original figure that Danielli and Davson proposed looks like this (from the <a href=\"http://onlinelibrary.wiley.com/doi/10.1002/jcp.1030050409/abstract\" rel=\"nofollow noreferrer\">original publication</a>):</p>\n\n<p><img src=\"https://i.stack.imgu... | [
{
"answer_id": 24051,
"pm_score": 0,
"text": "<p><strong>Problems with the davson danielli model :</strong></p>\n\n<ol>\n<li><em>freeze-etched micrographs</em>:</li>\n</ol>\n\n<p>This is a technique of rapidly freezing the cell and then fracturing them. The fracture occurs along lines of weakness and in... |
20,266 | <p>I understand that in PCR we're able to amplify only selected portions of the DNA... however despite reading it from multiple sources, I cannot figure out how this selection actually takes place.</p>
<p>I know that by using proper primers, one each for coding and template strands, we can direct the DNA polymerases t... | [
{
"answer_id": 20267,
"pm_score": 4,
"text": "<p>Note: In your PCR program you always set extension time.</p>\n\n<p>Case:</p>\n\n<ul>\n<li>Product length = 500bp</li>\n<li>PCR extension time = 50sec</li>\n<li>Assuming that polymerase adds 1000 nt/min</li>\n</ul>\n\n<p>Cycle 1:</p>\n\n<ul>\n<li>Strand th... | [
{
"answer_id": 20268,
"pm_score": 2,
"text": "<p>I'm not completely clear when you say \"what makes the replication terminate when the polymerase reaches the primer at the other end\" since when you perform a PCR you go through three phases. The denaturation, whereby the two DNA strands become single st... |
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