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Do bees know that they die if they sting? | Putting aside any speculation about the capacity of a bee to have knowledge, bee stings are not designed to be fatal to the bee. The bee only dies when it stings a creature whose skin is thick enough to "catch" the stinger, like a mammal. So, even if a bee had the sort of cognitive capacity to have expectations, then it would not generally expect to be killed upon stinging another creature. |
If I add sugar to lemon juice, what actually happens? Is the acid in the lemon juice neutralized or just masked? | There is a chemical reaction, the citric acid in lemon juice hydrolyzes the sucrose molecules and water into glucose and fructose: C*_12_* H*_22_* O*_11_* (sucrose)+H*_2_* O ⟶C*_6_* H*_12_* O*_6_* (glucose)+C*_6_* H*_12_* O*_6_* (fructose). This occurs at a faster rate if you heat the sugar-juice mixture, it also occurs (very slowly!) without any acid, but the acid serves as a catalyst. These sugars do taste different to sucrose, fructose is much sweeter, so this does at least change the taste of the sugar. As to what happens to the citric acid in the mixture, I don't think very much so I guess this flavour is masked by the sweet(er) sugar. |
Because it takes time for light to travel to our planet, does the universe seem to be expanding because farther light is reaching us? | Nope. Worry not; a mistake that simple wouldn't have propagated over hundreds of years! :) The expanding Universe has to do with redshift, very similar to the Doppler shift that makes the sirens of an approaching ambulance sound high, and then low after it's passed you. Light has a similar effect; when an object is moving away from you, the light that it emits in your direction gets stretched out. We can go out and look at lots of different galaxies, and find that their distance is actually proportional to their redshift; the further away a galaxy is, the greater its motion away from us. This is a clear sign that the Universe is expanding. |
Is AI even possible with conventional programming languages? | Conventional languages are Turing complete, which means that anything that can be computed, can be computed in such a language*. Assuming physicalism and hence the brain is nothing more than a physical system, then the answer is yes. If you're religious or whatever I can't help you. \* assuming the strong church-turing thesis. |
If a gravitational pull keeps the moon revolving around the Earth, and the same gravity keeps the Earth revolving around the Sun, then what force/object keeps the Sun (solar system) revolving around the center of the galaxy? | The moon doesn't orbit the Earth, it orbits the common centre of mass between the Earth and the moon, which is near the Earth's core due to our higher mass. Ditto the Earth around the sun, and ditto for the Milky Way. All the stars in the galaxy orbit around their combined centre of mass, which is around the centre of the galaxy. The arms are more complicated, and I'll defer that question to a proper astrophysicist. |
How are qubits stored and manipulated in quantum computers? | It really depends on the physical implementation of the qubits, as there are many kinds. An incomplete list of things that people use as qubits are: 1. The electronic structure of ions or atoms, which will be confined to some region of space by some sort of electromagnetic "trap". 2. A single electron's spin, where the electron has been trapped in a solid state system; a so called "quantum dot". 3. Superconducting circuits which have Josephson junctions can also be used as qubits. 4. Optical qubits use polarization or optical modes in light as qubits. Each kind of qubit is stored (I'm assuming by stored you mean kept free from noise) and manipulated differently. Is there a particular kind you're interested in? |
if i had two hard drives (same size, manufacturer, model) and one was full of information and the other was empty would the full one weigh more (even ever-so-slightly)? | If you have two sets of eight coins, and one of the sets was all heads-up, and one of them held the information for the number 137 (THHHTHHT), would the second set of coins weigh more? |
Why dose meat from different species of animals taste noticeably different? Isn't it the same stuff (biologically)? | It has to do with different proportions of proteins. White meat chicken breasts have mostly fast-twitch type muscle fibers (high in glycogen), fast but low endurance, which give the characteristic white meat flavor. But the legs are used far more often in a chicken, so they have more slow-twitch type darker fibers, which have higher endurance at the loss of power. This is why duck breast is darker and more gamey, ducks need the endurance fibers in the flight muscles for cruising. Once you move into "red meat" animals it is mostly slow-twitch fibers (rich in myoglobin), giving that red meat flavor. Additionally, different animals have different circulatory systems, making some meat harder to drain of blood, giving the metallic taste and darkness of a lot of game animals. At the darkest end of the spectrum is seal/whale meat. Their systems hold lots of blood in the muscles to aid in diving, and can't be bled-out as effectively. TL:DR Different proportions of proteins. |
Why do humans mature so much slower than other animals? | One of humanities adaptations is learning and tool making. That requires communication and cooperation. To achieve all of these goals we need long developmental periods in safe environments where we can accrue those knowledge and skills. The most simple solution to this is a long pre-adolescent period in a tight nit family group. |
Can a microwave oven interfere with wireless internet? | Both operate at ~2.4 GHz assuming you are not using the newer %GHz band routers. In theory the microwaves are contained by a faraday cage so not much should be leaking out. But if you take that your router is usually emitting in the mW range it takes < 1% of the radiation put out by a 1kW microwave to swamp the router signal. I don't know how much typically leaks but I would assume something on the low Watt scale would be accurate. |
Why does closing one eye help the pain when it's really bright out? | You "feel" bright light when the iris contracts and makes your pupils small. This is why photophobia is a common symptom of corneal abrasion and viral keratitis, and why browache results from pilocarpine drops that force the pupil to shrink. When you cover one eye, you reduce the stimulus to pupil constriction. The pupils still constrict (even in the closed eye) but the stimulus isn't as intense, so the response is not as "painful". |
Why do clothes shrink in the laundry? | What you see as the clothes shrinking, is actually the fibers in the clothes returning to their natural length. When fibers like wool and cotton are turned into yarn, they are stretched. This happens again when they're turned into pieces of clothing.This places a large amount of stress on the hydrogen bonds holding the fibers together. When you go on to wash these pieces of clothing, the heat and agitation they experience essentially release the tension that has been put into the fibers, and they return to their natural length. |
Why do human teeth grow in so crooked as apposed to say dogs? | In part, it's because we eat softer food. It turns out that eating hard foods is important in maintaining proper jaw development, tooth eruption, and tooth position. You see the same thing with various other animals raised on soft diets, including rats, rabbits, and alligators. Additionally, humans have significantly shorter jaws than our ancestors, but the same number of teeth, which means our teeth are pretty packed in there, causing them to be a bit jumbled. We actually see similar features in the jaws of dogs with shortened snouts, too, such as bulldogs and pugs. |
Why do a lot of little kids have freckles, but not that many adults? | Two theories about the prominence of freckles in children are as follows: 1. Freckles, being triggered by exposure to sunlight, are more common due to more frequent exposure to the sun and outdoors play, coupled with less care for sunscreen. 2. Freckles, being clusters of melanin, are more easily visible through the thinner skin of a child. On adults their presence becomes more subdued. As for redheads, there is likely a genetic correlation to freckling; the amount of freckles is genetic and is related to the presence of the melanocortin-1 receptor MC1R gene variant. |
What color is the sun? | The light from the sun has roughly a black-body distribution (see [here](_URL_0_)). This means it outputs light of all wavelengths, so in that sense it's white. However, the *peak* intensity occurs in roughly in the green range, so that's probably why your friend thinks it's green. |
Can we effectively mine landfills? | I saw a segment in a Louis Theroux documentary about a guy who makes a living 'mining' gold on/in the sidewalks of NYC. He'd dig in the cracks of the sidewalk and find little bits of gold, diamonds and other precious metals/stones that had been dropped over the years and ground into the dirt. Apparently he made a living selling it. It was pretty crazy. |
Why is gold and copper not silver/grey coloured? | The inner electrons for gold are orbiting so quickly that their mass increases due to relativistic effects. This causes their 'orbit' size to increase. The elctrons in the outermost orbits are affected by this shift so that instead of absorbing ultraviolet light they now absorb more blue light. If you are a substance that absorbs more blue light you start looking redder. TLDR; relativistic effects. |
Jolt when falling asleep | It is called a [Myoclonic](_URL_0_) Jerk. It happens because your brain misinterprets your muscles going limp as you falling. |
What causes that Jolt just when you're Falling Asleep? | _URL_0_ > A hypnic jerk, hypnagogic jerk, sleep start, or night start, is a myoclonic twitch which occurs during hypnagogia, just as a person is beginning to fall asleep, often causing them to awaken suddenly for a moment. Physically, hypnic jerks resemble the "jump" experienced by a person when startled,[1] often accompanied by a falling sensation.[2] |
How is a Honey Bee's sting evolutionarily advantageous if it dies after using it? | It's less about the survival of the individual honeybee and more about the survival of the colony. If a small number of bees attack an intruder and fend that intruder off, then the colony survives even though a small number of individuals died defending it. There's really no selective pressure to produce more robust and stronger individuals because that would make each single bee more energy dependant and that would be less economical to have a colony of strong bees that have an exponentially higher calorie demand opposed to a bunch of weaker,more energy efficient bees that suffer a few casualties while defending the hive |
One of the more dangerous parts of bee venom is Phospholipase, which breaks down cell membranes. Why doesn't it break down cell membranes inside the bee? | After a bit of research, I think I found your answer. Apitoxin (bee venom) has an active component called [melittin](_URL_0_), which is a peptide. Melittin stimulates the enzyme [Phospholipase A2](_URL_1_), or PLA2, which as you stated recognizes phospholipid structures and hydrolyzes them. However, in melittin, the PLA2 is secreted extracellularly, and is only activated by Ca2+. Melittin acts as a regulator for the calcium concentration, as it increases the permeability of Na+ through the membrane, thus indirectly increasing the intake of Ca2+ through the exchange. So, in short, the phospholipase does not break down cell membranes inside the bee because it is not active until is secreted by the sting. Hopefully I answered your question :) |
Why isn't water flammable? | When you burn hydrogen in the presence of oxygen, water is the *end product*. It can't be 'burnt' because it's already been 'burnt.' |
Can plants become obese? | That's not the way plants work. They make their own energy rather than taking it in from the environment in their "diet". Plants store their energy in the form of starch rather than fat. They use this starch to either grow or reproduce. Some plants store lots of starch in their roots (eg potatoes), but the concept of obesity just does not apply to plants in the same way as it does for animals |
What distance would a star, similar to our sun, need to be in order to be visible during the day? | In order to be **just** visible to a trained observer (~ -4 mag) the star would have to be roughly more than half a lightyear away. To be clearly visible for the average person (~ -6 mag), it would have to be about 0,22 lightyears away. |
Why do shower curtains attack? | I'm going to take a stab and say that the egress of one person starts a circulation airflow and the warm shower air is flowing upward and drawing cool air from the rest of the bathroom in under the shower curtain. |
Are all galaxies moving in the same direction? If not why? | > From what I understand the universe is constantly expanding from a central point from the big bang or huge cosmic explosion or what have you There is no central point. The Big Bang wasn't an explosion. See the [FAQ](_URL_0_). It was an event in which the whole universe began uniformly expanding. All points started receding from all other points, because additional space was being created in between them. This wasn't matter traveling through space, this was space itself spreading out. The universe is thought to be infinite, or at least so obscenely large that it can be easily mistaken for infinite. Galaxies tend to have some random intrinsic motion relative to nearby galaxies, this is known as "peculiar velocity". Within galaxy groups and clusters (like the Local Group, where we and the Andromeda galaxy reside), galaxy motions are dominated by their gravitational attraction toward each other, and that is what is pulling us and M31 (Andromeda) toward each other. |
Many galaxies are moving away or towards us. Are there any galaxies that aren't moving considerably, or have more sideways movement than in and out? | Measuring the sideways motion of galaxies isn't something we can really do. However there are nearby galaxies with have negligible velocity (relative to us) in the radial direction; in these cases, you can safely assume that their sideways motion (relative to us) is the larger component. |
How did certain herbivorous dinosaurs grow so large on a diet of plants and leaves? | First, oxygen is _not_ the reason dinosaurs were so large. Oxygen levels in the Mesozoic were not much higher (and were sometimes lower) than they are now. Second, organism size has less to do with diet and more to do with the adaptations of the organism. There's a good description of why sauropods got so large [here](_URL_0_). Things on the "primitive" side were traits sauropods already had (and shared with many other dinosaurs). Traits on the "derived" side are sauropod special adaptations. Basically, dinosaurs were just really different than today's elephants. They ate differently, breathed differently, reproduced differently, had different bones and different body shapes. This all helped them become really huge. |
In a photo of Andromeda galaxy (example in text), are any of the discrete-looking stars in Andromeda, or are they in the milky way? | Those are in the milky way. When a supernova goes off in a distant galaxy, it looks like a new star has lit up: _URL_0_ |
What happened to peoples' teeth before brushing teeth was a "thing"? Why are animals' teeth so clean without brushing? | Animals do clean teeth, but with different methods. If you have a cat or a dog, you probably noticed they sometimes chew on grass or something similar. |
What actually is balding? | Humans go bald when their hair follicles revert back to vellus hair, which is the hair that first grows on newborns and is also known as peach fuzz. Hair has three different stages, anagen (growth), catagen (when the follicle stops growing and begins to get pushed up) and telogen (resting phase). Balding occurs when certain transcription factors fail to activate and hairs in anagen stage prematurely enter the telogen phase, resulting in baldness. I learned all this in my Cell and Developmental course in college, so only know how it happens. Hope this is helpful! |
Why does a gas powered car need a transmission but an electric vehicle doesn’t? | Combustion engines have a relatively narrow range of rotation rates where they can operate. When turning slowly, they are inefficient and [produce little torque, or cannot run at all](_URL_1_). That's because the force provided from a combustion event has to synchronize with the expansion of the cylinder volume, or the energy it represents ends up being wasted. If the cylinder is opening up too slowly, the fuel cannot fully combust. And each combustion event has to rotate the crank at least enough to enable the next one in the cycle. This is also why gas cars need a "starter;" the engine must already be turning in order for it to work. An electric motor, on the other hand, can produce torque at zero RPM, and while there is a "torque curve" it's [shallower and wider](_URL_0_) than that of a combustion engine. Most electric vehicles are actually geared down because the most efficient range for the motor is very much faster than typical wheel RPM but it's a single, fixed gearbox. |
Why do old people smell like that? | [2-nonenal](_URL_0_) > In the April 2001 issue of the Journal of Investigative Dermatology, Shinichiro Haze, et al. published an article entitled: "2-Nonenal, Newly Found in Human Body Odor Tends to Increase with Aging". > In this article they reported on their work which involved the analysis of body odor components collected via headspace gas chromatography/mass spectrometry, from shirts worn for three days by subjects between the ages of 26 and 75. They found that the concentration of many components of body odor were unaffected by age. They found that the concentration of 2-nonenal tended to increase with the age of the subjects, and determined that that 2-nonenal is generated by the oxidative degradation of omega-7 unsaturated fatty acids, such as palmitoleic acid and vaccenic acid, found on the skin surface. As a chromatographer this doesn't sound very fun. |
Why does one nostril allow more airflow than the other? | Its called the nasal cycle. People actually breathe only from a single nostril which cycles throughout the day. I'd link you to the Wikipedia article, but... |
What exactly is a decibel | Well I did some googling and a decibel is actually a ratio of power the number of units being equal to a constant times the logarithm to the base 10 of the intensities of two sources. Now this at first seemed strange to me because I thought, what two sources? I've always heard it in reference to how loud one sound is. As it turns out they (somewhat) arbitrarily pick a reference point of 20 micropascals (20 μPa) which is really really low but I read that this is the limit of sensitivity of the human ear. I also discovered that the decibel doesn't necessarily denote loudness perse because the human ear is more sensitive to certain frequencies. I guess I should have tried googling it first but I always prefer having someone explain things. [Source](_URL_0_) |
What is happening inside of the tip of our fingers and toes that causes nails to come out and grow? | Basically, the base of the growth is situated at the part of the nail that is closest to your wrist (when your fingers are extended). Your skin folds over itself at the base, forming a sinus - a cavity in the external body in this case. All the walls of this sinus are external surfaces of your skin. In the base of this sinus, an area of skin express a large amount of keratin. Because of the shape of the sinus, growth of keratin-rich young cells pushes older cells out across your finger. This pushing compress the growing cells into a dense matrix of dead cells and keratin. So, your fingernails are just dense, flattened, protein-rich skin-cells. Because they were pressed together like that they form a strong matrix of multiple layers. If you're asking why only cells on that part of your body grow this way, I'm not prepared to answer that. |
Is there any real world applications where concept of infinity is used? | Infinity in what sense? Limits at infinity are super important for some of the most fundamental aspects of calculus, which is certainly useful in real world applications. |
Why do stars explode in an "hourglass" shape? | Supernova remnants are usually quite irregular, as example [the crab nebula](_URL_4_) but when a non-super massive star (like our Sun) dies it just loses its outer hot gas layers into space, this is called later a Planetary Nebula, these hot gases expand following different kind of symmetries really basen on the initial conditions of the dying star like rotation speed, nearby stars, etc... The resulting nebula not exclusively takes your "hourglass" shape, but also are common [spherical symmetries](_URL_4_), [irregular shapes](_URL_4_), and [totally awesome structures](_URL_4_). BTW those examples are IC3568, NGC6326 and NGC6543. |
Would a box of photons have mass and therefor be "heavy"? | Yes, that quote is correct and so are your conclusions. If you have a box of photons all moving in random directions, the photon gas inside the box will have mass, and the box will be harder to accelerate (for a given force) than an empty box (nevermind how you'd get a box to actually be empty of photons; assume the walls are at absolute zero if you wish). |
Are microwave ovens bad for you? | No. Microwaves are a form of radio waves. Radio waves are a natural part of the universe and are constantly surrounding you. Right now, microwaves are constantly bombarding you from every point in the sky due to waves left over from the big band (the CMB). You are also constantly being hit by radio waves created by lightning bolts on distance continents (Schumann resonances). Radio waves are harmless (unless they get strong enough to burn you). Humans were being bathed in radio waves long before technology came along. |
What causes an "aftertaste"? | [Here](_URL_1_) is a good article on the subject. The basics of it are that how we perceive flavor is based on texture, temperature, smell, and taste. Flavor here is separate from taste, as flavor is the entire ensemble of senses coming together to allow you to experience food. While there is no definitive consensus, as how we perceive flavor is not yet entirely understood, the leading theory on aftertaste is that it is our bodies experiencing flavor after the elements of temperature, texture, and smell are gone. This leaves us to process flavor with only the 'taste' of what we had eaten left. Disclaimer: I have no prior knowledge on this subject beyond what I just researched on the internet. The website is a wordpress site, but it cites published research to back up its claims. If someone in this field disputes what I've said, they know much more than me and are actually qualified to give answers. Citations given on the website: _URL_3_ _URL_2_ _URL_4_ _URL_0_ _URL_5_ |
Will it ever be possible to record dreams, and be able to watch them when awake? | Neuroscientists do things with brain imaging and EEG to capture the signals that the brain emits when it thinks, but they aren't anywhere close to making a log of the brains activity. In two decades, *maybe* someone will float a feasible "this might work" idea about doing stuff like this, but no one is doing it now. Have you seen the movie "8 1/2"? It's basically a movie about how hard it is to put your inner life into a form other people can understand (let alone empathize with). |
Have trees ever evolved over time? Or are they relatively the same as they were hundreds of millions of years ago? | Trees have evolved so much that the trees which dominate the world now aren't even all that closely related to all the different groups we loosely call "trees". The first "trees" where tree-ferns, whch were more closely related to modern ferns than any other living plants (and as such, had a radically different life cycle than the gymnosperms and angiosperms we are used to today.) In fact, the angiosperm (flowering plant) trees that dominate today didn't even evolve until the end of the Cretaceous, making them younger than mammals and dinosaurs. |
What do nebulae and other stellar phenomenon actually look like? | This might not fully answer your question, but it would probably be worth your time to check out [this thread](_URL_0_) from a few days ago in r/astronomy. Read both dVnt's post (which is what the link is to) and doctorBenton's response. |
What do we have earlobes? As in, what purpose do they serve. | As with the outer ear its design is to help funnel in sound. Obviously some people have attached vs free earlobes and have no hearing difference. Just a leftover part of evolution, as we dont know why some parts of the body are X way vs others. And keep in mind something like an earlobe is not an evolutionary hindrance thus it remains. |
Why does male pattern baldness follow the pattern it does? i.e. from the top of the head down, often in a perfectly straight circle around the head. | So it's well knows that male pattern hair loss is due to dht which is the highly potent version of testosterone which is a steroid promoting tissue growth. Ok anyway dht is known to cause thinning of the follicle. There is a theory on the specific pattern and it's called the gravity theory... Goes like this... As men age there is decreased fat in the face and scalp hence less support and the areas that tend to bald are the areas that have the most gravitational pull leading to damage. The damage then requires testosterone for repair leading to a buildup of DHT in the area... Bada Bing bada boom. Of course this is thought to prove but it is absolutely a fact that there is a buildup of DHT in the balding areas compared to the spared areas. |
Are there neurological differences between speakers of different languages and people who speak multiple languages? | _URL_0_ > The Japanese language has thus a unique grammatical structure and native lexical corpus whose idiosyncratic syntax and connotations condition the Japanese to think in peculiar patterns unparalleled in other human languages. The Japanese language is also uniquely vague. Foreigners who speak it fluently therefore, may be correct in their usage, but the thinking behind it remains inalienably soaked in the alien framework of their original language's thought patterns. This is the Japanese version of the Sapir–Whorf hypothesis, according to which grammar determines world-view. not so much an answer, but a lead. hope it takes you somewhere. |
Why hasn't the asteroid belt amalgamated to form a planet or planetoid? | There really isn't enough material in the asteroid belt to coalesce - it's very sparse, totaling a small fraction of the Moon's mass. Jupiter's gravity will prevent (and did prevent in the early solar system) large masses within the belt growing through accretion anyway - the high speed of the collisions do not encourage planetary formation, but rather the asteroids simply shatter. Those that can avoid shattering can easily find themselves straying into a zone where Jupiter or Mars' perturbing effects will drag them out of the belt. |
Why hasn't The Asteroid Belt formed a planet? | The total mass in the asteroid belt is quite small - much smaller than any planet, even much smaller than Pluto. That means a lower gravitational attraction between the objects, and a much longer timescale for the collisions of them (longer than the age of the solar system). In addition, Jupiter perturbs the orbits. |
Why does smoking tobacco cause so many illnesses? | Smoke: physically damaging to the lungs due to heat and irritation by carbon/chemical deposition. This causes most of the lung disease- COPD, asthma, etc. Lung cancer is in part from this, also because some of the chemicals are carcinogenic on their own. Cardiovascular: a big part of this is nicotine, which raises your blood pressure. BP is an important determinant in heart disease and atherosclerosis. There may be more direct effects as well. carcinogens: as mentioned above, carcinogens cause cancer. Lung (obviously), mouth/throat, bladder (where many are disposed of after your kidneys remove them from the blood) are especially prominent. |
Why is there so much Carbon-14 in these fossils? | There's a lot of crap on that page. First, carbon dating doesn't work for things like dinosaur fossils. They're too old. The number 22,380 has no reference next to it so I'm not sure which reference at the bottom they're referring to. The premise of the article is that in 2005 a fossil was dated to 20-30k years. None of their references seems to point to this event, nor does Google come up with anything that's not a blog or some anti-evolution web site. Hugh Miller comes up a few times, he's apparently a creationist. There's nothing on that page that can be responded to without vomiting. |
If I have the flu, and I am next to my dog coughing and what not, why doesn't he get the flu? | The epithelial cells in his respiratory tract and his erythrocytes don't have receptors for the virus. The influenza glycoprotein hemagglutinin needs to bind to a cell surface molecule known as sialic acid inside its human host. |
Can dogs transfer viruses like the flu to a healthy person through interaction with someone who has been infected ? | Yes. Dog licks face of a person with flu virus, gets some runny-nose mucus on their tongue, and then licks your face and mixes that mucus with your own saliva or eyes or mucus lining of your nose. A couple days later and you feel like something that came out of the other end of the dog. A dog won't *catch* the flu and then transmit it to you, but it can certainly mechanically carry it to you. |
Can the Universe be bigger than we think it is? | we know that it's bigger than the observable universe for sure. Most likely, it's infinite in size. |
Can people with Dyslexia read their own writing? | We can read all writing. There are just a few hurdles we need to jump that the average readers don't. It is esay for poelpe to raed sracblemd wrods if the frsit and lsat ltetres ramein the smae. First, scrambled letters are more of a misconception of dyslexia. I personally don't see scrambled letters. It almost as if I don't see the letters at all, when I read. I actually do, but I'm saying that to give you an idea of what it's like. Re-read the scrambled letter sentence above and kind of blur each word to the point where you know what the word is and move on. That might give you an idea of what it's like for me to read. |
Our solar systems mass minus the sun, does that equal enough mass for another star? | Not even close. Jupiter is the dominant source of mass besides the sun, and it is about 1/80th the mass necessary for a star. |
Do animals share a similar left handed or right handed distinction as people do? | Dogs have apparently been found to have different temperaments which can be determined by being left or right "pawed". I found a link to an article but can't guarantee accuracy: _URL_0_ |
Are programming languages handled differently by the brain than oral and written languages? | I'm no neurologist but i would expect some more is going on than just phrasing syntax. In programming languages your not just phrasing something to describe an event or piece of information. Your predicting the behaviour of the system that is defined and how it interacts with a larger system. It could be compared to how a paragraph interacts with an overall essay, but this i think is not a good comparison. Try to think about how recursive algorithym calculate various types of data, then compare that to how objects in a simulation are written to interact. The brain needs to predict how those systems will interact once compiled. Whereas in a written piece of text there is no real interaction between once sentence to the next. I could be writing about this topic, and then the frog lord took his rightful place, in the larger picture it doesnt make a real difference. Even if it feels a bit disjointed, it doesnt stop everything else from breaking down horribly or spiraling out of control. |
It seems all craters from collisions with meteorites are round. Can a meteorite hit a substantially bigger celestial body at an acute angle? If so, what kind of trace will it leave on its surface? (I'm not a native speaker, sorry for potentially obscure wording) | Impact craters are almost always round because the crater isn't formed from the imprint of the actual object that hit the surface. The force of the impact on the surface is so large that it essentially creates an explosion/blast wave that causes the crater (and can often completely destroy the impacting object itself). Those waves move out symmetrically and cause a circular crater much larger than the size of the actual object that came in. |
Why doesn't beer aged in barrels lose alcohol due to evaporation? | Law of partial pressures... Since the barrel is sealed, the alcohols will evaporate up to a pressure in the 'atmosphere' of the barrel, that will be equivalent to the liquid pressure of the alcohols in the solution. I.E. - Any alcohol molecules will as some point achieve a density/pressure, equal to that of the density/pressure of the same molecules in the liquid _URL_0_ Specifically reference Henry's Law within the Partial pressure derived equations _URL_1_ |
Why is it that some beers, when bottled in colored glass and stored out of direct light, will continue to "age," while others just get "skunky"? | Unless they are pasteurized, most beers, even after filtering, will contain a complex community of living bacteria and yeasts. While hanging out in a bottle, these microbes can do various things: * Produce chemicals (e.g. thiols) that give the beer a skunky taste * Produce more alcohol * Produce nice tasting chemicals that 'age' the beer Higher alcohol, unfiltered (i.e. lots of microbes) beers seem to age better, likely in part because the alcohol selectively inhibits the growth of the skunky-making microbes. Refrigerating the beer will slow microbial growth, and thus their production of nice/gross chemicals. Any microbes that are unable to tolerate the colder temperature will die, although many can withstand refrigeration and so could continue doing their thing once returned to room temperature. Incidentally, [here's a cool paper](_URL_0_) that discusses how the community of bacteria and yeasts in spontaneously fermented beers changes throughout the fermentation process. |
Why do clouds turn a dark grey when they are filled with rain? | The darkness of clouds has to do with particulate density. Clouds are basically water vapor that appears when the humidity reaches or gets close to the dew point. The cloud obscures light. The thicker or more dense the cloud the more sunlight it blocks making it appear darker from underneath. So, "filled with rain" might not be as accurate to say as saying "dense with condensed water vapor" or to say "the cloud is thick". Either case would have the same effect of darkening the could. |
Is there at least 1 molecule of Dealer Gas in my car after 10 years? | The solution is relatively easy, as what you're doing here is no different from a serial dilution (assuming homogenous mixing after each fill up): You have 1 tank, and you're doing 1:10 dilution 520 times. This gives a dilution factor of 10^520. Your original tank of 50 L of gasoline (we'll further assume it's pure octane, since gasoline is a mixture of a large number of organic compounds) will have 35150 g of octane (density of 0.703 g / mL), which is 307.7 mols of octane. Apply the dilution factor, and you get 3.077 x 10^-518 mols octane (from your original tank) in your final tank. This translates to 1.8 x 10^-494 _molecules_ of octane. Since molecules are indivisible, you can say there is a 1.8 x 10^-492 % chance 1 original molecule remains. This also happens to be the exact same calculation for why homeopathy is BS. |
Why are we born with black/brown/blonde/red hair and not other colours such as pink/blue/purple? | Because hair, like skin colour is determined by melenin and the most common type in humans that makes up hair colour is Eumelanin which is Brown/Black _URL_0_ |
Are there people who exist on the opposite end of the spectrum from sociopathy- i.e. an "anti-sociopath" or a hyper-empathic individual? | The closest condition that I can think of like this is called Williams syndrome (_URL_0_). People who have it tend to be overly trusting, cheerful and friendly. They also have a distinctive appearance and some negative physiological symptoms. However, I believe that being tooooo trusting can lead to a few problems. |
How do we get vitamin(s) from the Sun? | The energy from the sun is used as part of the process that your body uses to create vitamin D2 and D3 precursors. The sunlight itself is not converted into matter, it's used an an energy source for the reaction. |
If we shed dead skin cells, how does the sun permanently affect our skins appearance? | [Photoaging affects the connective tissue of the dermis](_URL_0_), which underlies the epidermis. The layer of skin that is constantly being replaced is from the basal layer of the epidermis, which grows 'outward' and differentiates into the anucleated keratinized cells of the stratum corneum. Thus, dermal components do not get 'shed' as epidermal components do. UV radiation also induces fibroblastic changes that again affect the CT (collagen and elastin, primarily) of the dermis. |
How is the formation of memories blocked in Alzheimer's disease? | You are not alone in not understanding this process! In AD, there is early loss of synapses and then overt neuronal death. These events start in the hippocampal formation, an area of the brain involved in processing memory traces and routing them for permanent storage. Exactly how or why this is occurring is unclear, but you're right that buildup of extracellular plaques and intracellular tangles are hallmarks of the disease process. Depending on which expert in AD you talked to, they could make a strong case tying each, both, or neither of these histopathologies to blocking memory formation. |
Do computer processors slow down as they age? | I found an interesting article on this topic here: _URL_5_ What I get from it is that transistors do wear but the effect is compensated during the design phase so you shouldn't notice any performance hit. Eventually your cpu will die however. |
Why do computers get slower as they age? | The hardware in a computer does not gradually deteriorate, producing slower performance. It's also very sensitive hardware. If it physically deteriorates to the point where something no longer functions (a particular pathway doesn't conduct electricity, or something gets too hot), then the affected part will die quickly and suddenly. This is why you have people who just experience that their "computer died". Some part died and there was no warning. The exception to this are mechanical hard drives, which are very different from other computer parts - they have very fine moving mechanisms, and they read and write data very slowly, so a dying hard drive may first have a significant slowdown before dying. Computer slowdown over time is pretty much entirely due to software. You get more and more software onto the computer, the operating system and other old software get updates that do more stuff and therefore are more power hungry, and so on, and so on. |
If the human body is only around .3% iron, why do I taste iron if I taste blood? | Because red blood cells in plasma contain high levels of haemogoblin which is mixed with oxygen to form oxyhaemogoblin haemogoblin has high levels of iron(as well as other elemntshttp://_URL_0_) so thats why if u taste blood, the flavour will be iron like. ps: sorry for my english, im natively spanish and i study english as a third lenguage. |
Would anything on Earth be a different color if the sun were a different kind of star? | If we orbited a cooler star which output more light in the near-infrared than the visible, it is possible our plants would have devised a method of photosynthesis which uses lower energy photons making our green leaves appear black. Here is a whole article devoted to this subject _URL_0_ |
Why do galaxies collide with each other, even though the universe is expanding? | Gravity. If the galaxies are close enough, gravity overcomes expansion. |
Is there a ratio for helium/oxygen to make a balloon consistently 'hover' at a given height? | There are a lot of variables in there; oxygen is only slightly denser than air (~80% nitrogen, atomic mass of 28, and ~20% oxygen, atomic mass of 32 g/mole, for an average of 28.8 g per mole of air molecules- ignoring all other gases, which are a relatively small proportion). One would need to account for the mass of the balloon, for example, as well as the (slight) compression afforded by the latex, increasing the pressure and, therefore, increasing the density. Helium is 4.00 g/mole; a helium-air mix (assuming complete mixing) would hit the density of air (28.8 g/mole, as discussed above) at a proportion of something like 9% helium and 91% oxygen. |
What is happening chemically when cooking oil is heated past its smoking point and it begins to smoke? | It's pretty straightforward reaction. [Here's a triglyceride with fatty acids and glycerol labeled.](_URL_0_) Upon heating, oxidation occurs at the ester bonds, releasing glycerol and free fatty acids. It's also possible that high heat can increase the presence of free radicals, which are highly reactive. Additionally, high heat can introduce double or triple bonds in the fatty acid chains, increasing the amount of trans fat. The health effects of any of the above are unsettled scientifically. |
Does an oil's smoke point affect baking as well as frying? | This page gives a good run down of the typical surface and interior temperatures for baking bread. Cakes will be not too far off although maybe a little cooler due to the additional liquid content. Smaller drier items like cookies will be hotter. Roughly surface temperature will be about 10 to 20% cooler than the oven temp and interrior temperature will max out about half the overn temperature. _URL_0_ Interior temperatures shouldn't get to flaxseed's smoke point. The surface temperatures will do. There won't be much of the oil contained at the surface so it probably isn't a huge issue. Certainly not something I'd personally worry about as someone who likes bbq meat. |
Are there enough asteroids to make mars significantly bigger? | No, the mass of the entire asteroid belt is about half a percent that of Mars. |
Why is sugar "sticky" but sugar substitute (which shares a similar structure) not "sticky"? | Hey there, carbohydrate chemist here (I am doing my master's in this field). I work with two main types of sugars at the moment, galactose and N-glucosamine. There are some physical properties I noticed when doing any sort of chemistry on these molecules. I am taking an educated guess here and will say it has to do primarily with the hydrogen bonding of the -OH groups on the sugar and how it forms a lattice with other sugars/solvents. The different configurations of each hydroxyl group determines the type of sugar (ie glucose and galactose has 1 -OH group that differs in configuration, a C4 epimer). So it is to my understanding, especially doing chemistry on these types of sugars, that the configuration of the substituents on each sugar plays a role in the lattice network formed which may explain why some sugars are more "stickier" than others. I hope that is a somewhat decent explanation... |
How much more rain does California need before it's out of drought trouble? | The drought in California has 1 measure and it is snowpack. For California to get out of drought the state needs a snowpack over 40 inches(across the whole mountain range) and maintain it from the months of November to March. 2013 snowpack averaged 25 inches, 2014 snowpack average is 8 inches thru February 1st. Snowpacks will fill the reservoirs. |
How much rain is needed to get California out of their drought? | [11 trillion gallons](_URL_0_), according to NASA. Several years worth. But underlying the drought are arcane water rights and poor agricultural choices. There was water available and western states badly mismanaged it. Now they can't have nice things. |
If the universe is expanding and everything is moving away from each other, why do galaxies collide? | There are two issues here: > If everything came from a singular point ... The universe is expanding, but it did not come from a point. In fact, it may have always been infinite. See [this FAQ](_URL_0_). > and is expanding outward, how do galaxies get on collision courses with each other? The cosmological expansion only dominates on vary large distance scales (larger than about 10-20 megaparsecs). At smaller distance scales, one has gravitationally bound objects: stars, galaxies, clusters of galaxies, *etc*. Within these bound objects, the motion of the constituents is dominated by their interactions and collisions can happen. |
Why are nearly all impact craters circular? | The short answer is that the energy involved in an impact is so huge that when the impactor hits the ground, it explodes like a bomb, rather than just denting the surface like a rock thrown into mud. Explosions are generally symmetric, so the resulting crater from most impacts is circular. Only very very shallow impacts form elliptical craters, but they do exist! A more extensive answer to this question can be found at Scientific American. |
Why does the air pressure in the car fluctuate and hurt your ears when you are driving fast with only one window open? | The open window in your car makes your car act as a [Helmholtz resonator](_URL_0_). This is characterised by fluctuating air pressure in the cavity (which you're sitting in). As to why your ears hurt, that's a medical question that I cannot comment on. |
How and why does lactose intolerance suddenly happen in adults? | So in most people, lactase, the enzyme that breaks down lactose, stops being expressed (made by your body) after childhood (when you would no longer be drinking your mothers milk back when we lived out in the wild) Making the enzyme costs your body energy it could be using elsewhere and so we have evolved to stop making the protein after childhood. However, in some Northern European and African populations, people have had mutations to the pieces of dna that dictate when lactase is made which in turn results in what is called “lactase persistence” or lactase being made your whole life. |
How is Schizotypal Personality Disorder different from Schizophrenia? | "Schizotypal personality disorder can easily be confused with schizophrenia, a severe mental illness in which people lose contact with reality (psychosis). While people with schizotypal personality disorder may experience brief psychotic episodes with delusions or hallucinations, the episodes are not as frequent, prolonged or intense as in schizophrenia. Another key distinction is that people with schizotypal personality disorder usually can be made aware of the difference between their distorted ideas and reality. Those with schizophrenia generally can't be swayed away from their delusions." quote from: [_URL_0_](_URL_0_) & #x200B; |
If helium rises, and we've "used" nearly all of it that we have, and it's a noble element, shouldn't their be a bunch of helium being held against the inside of our atmosphere? | Helium actually escapes the atmosphere. Keep in mind there is no magical barrier that defines the boundary of the atmosphere - it's all held together by gravity. Helium is light enough that it floats to the top, and gravity is too weak to retain it. Also, from the thread you linked to - helium used for balloons is a very, very small percentage of total usage, so reducing that usage has next to no effect. |
What is the difference between induced pluripotent stem cells and embryonic stem cells? | Embryonic stem cells are pluripotent stem cells derived from the inner cell mass of a blastocyst. Induced pluripotent stem cells are cells that have been reprogrammed from a differentiated to a pluripotent state by the introduction of ectopic transcription factors. Part of the definition of pluripotency is the ability of a cell to contribute to an entire embryo when implanted into a blastocyst. Induced pluripotent stem cells are indeed able to do this. The ability of iPS cells to contribute to chimeric mice was demonstrated independently by several labs, including those of Shinya Yamanaka and James Thomson, in 2007. The most stringent test of pluripotency is what is called a "tetraploid complementation assay". In short, the iPSCs injected into the blastocyst must alone produce an entire viable mouse, without help of ESCs from the blastocyst. iPSCs passed this test in 2009 and this is described in the paper linked [here.](_URL_0_) |
Are there any powers of pi that are rational? | Nope, π is what is called [transcendental](_URL_0_), which means that there is no way to make π into the root of a polynomial with rational coefficients. If π^n =p/q then π would be a zero of the polynomial x^n -p/q , which can't happen for a transcendental number. |
According to a documentary I was watching, the universe initially expanded faster than the speed of light during the big bang. How? | You're asking about [cosmological inflation](_URL_0_). Though you can't transmit matter or energy faster than light, you can stretch the space between them faster than light. |
Why does a mirror appear to be silver? When it in fact reflects all light? | Any perfect mirror will appear silver. Silver in that sense is not a colour but the appearance of a metallic object. So you associate high reflectivity with "silver" even when the mirror is not actually grey. White objects are objects which scatter light of all wavelengths, not objects which reflect light of all wavelengths. |
Instead of all matter distributed in near-circular clouds ; Why do galaxies have a considerably flattened shape? | It's a specialty of 3 Dimensional space. A system of randomly moving particles has one net angular momentum. Consequently, there is a plane on which the whole system rotates.Over time, all momentum in the dimension orthogonal to this plane will cancel out through collisions. What remains is a flat disc. [This](_URL_0_) video does a really great job explaining this phenomenon. |
Would the sun be brighter if we could see UV rays? | Not really. UV radiation makes up [less than 10% of the sun's light](_URL_0_) at ground level: the majority of UV light is absorbed by the atmosphere. To give you an idea of how minor the effect would be, that's comparable to the change in brightness [between July and January](_URL_1_) due to Earth's elliptical orbit. |
Why do some trees have purple leaves? | The colour in leaves is a function of the coloured photopigments in the tissue. While chlorophyll absorbs red and blue light effectively, it reflects most green light instead of absorbing it. Other pigments absorb other colours, with anthocyanins absorbing green better but not as much with red or blue and thus a red(dish) colour is observed. When chlorophyll breaks down in the fall, the other photopigments like anthocyanin take longer to break down, and as such leaves can change colour to yellow/brown/red as fall progresses. With purple leaves, these trees have more anthocyanin, leading to the purple colour. This can help a plant with predation of leaves, since plants/trees with this colouration tend to have phenols appearing with them that deter herbivores. Alternatively it can help with excess sunlight, which can be problematic for photosystems, in the form of a lot of reactive oxygen species being generated which can inhibit the efficiency. |
What evolutionary reason is there for ticklish behavior? | I don't know, but with regards to the question I'd like to point out that there doesn't necessarily have to be a evolutionary reason as such. It could be just a result of random genetic drift that never got selected against. After all, a non-ticklish mutant probably doesn't have any particular survival/procreation advantage. Or it could be a side-effect of something else or a vestigial trait or an emergent property. |
Was there ever really a hole in the ozone layer? | [Yup.](_URL_2_) They still is one, but it's predicted to become smaller--which is thankfully due to the drop in [atmospheric CFCs](_URL_3_) since they have been banned/phased/phasing out. However, it's best not to think of it as a literal hole, it's the reduced concentration in Ozone in one strata of the atmosphere. It's more like a "thinning." Not only that, the size of the thinning is seasonal and happens mainly at the poles--though NASA released a report predicting a future global Ozone depletion had CFC emission not slowed down. Here's a couple more images: * [Arctic Ozone depletion](_URL_1_) * [Seasonal Ozone minimums over the years](_URL_0_) |
Has the ozone layer recovered from where it once was? | It’s starting to recover, but the recovery has been a bit delayed by some volcanic eruptions. It’s not expected to fully heal until 2050-2080. _URL_0_ |
Why can I taste salt but not smell it? | Chemicals you can smell are volatile (small molecules that evaporate readily). It's the vapor that triggers a reaction in your smell receptors. Table salt forms a stable crystalline lattice which doesn't allow it to evaporate under normal conditions, which is why you can't smell it. There's literally nothing coming out of it to carry the smell. Furthermore, table salt (NaCl) is an ionic compound - if it would evaporate, it would be chlorine gas (lethal) and solid sodium (a metal that ignites when exposed to normal air). That would ruin your whole day. |
Why does salt seemingly have no smell compared to its intense flavour? | Salt is an ionic lattice of sodium and chloride ions. They are strongly bound to each other and stay as a solid. The chemical term for substances that can easily become a vapour is volatility and because of the lattice energy that hold the sodium and chloride ions together salt has a very very low volatility. This means that no salt becomes airborne and hits your nose, hence no smell. As others have mentioned taste and smell make up flavour salt tastes very strong but has little smell. |
When I am about to cry or feel like crying, what is that "lump" feeling in my throat? | Not an expert, but [here is a decent explanation](_URL_0_) Basically, we go though a small fight or flight response because our ancestors only really went through these emotions in stressful situations or life-threatening circumstances. Part of this is to open up the airway. > An important part of opening the throat to allow the lungs to get more air involves expanding the glottis - the muscle which controls the opening from the back of the throat (pharynx) into the voice box (larynx) - so that more air can pass through it. So part of the autonomic response of crying is to use throat muscles to open the glottis as wide as possible. This doesn't pose a problem until you want to swallow; swallowing involves closing the glottis, so that food doesn't get into your larynx. So if you try to swallow while you are crying, the muscles for swallowing are fighting against the muscles for crying, and this tug-of-war over the glottis is perceived as a lump behind your larynx which makes it difficult to swallow. |
Hey AskScience, how does the sun make colours on fabrics and other materials fade over time? | Photodegradation breaks chemical bonds of dyes. Found here: _URL_0_ |