Question stringlengths 15 75 | Domain stringclasses 3
values | Topic stringclasses 17
values | Explanation stringlengths 89 1.84k | Intended Educational Background stringclasses 3
values | Source stringlengths 20 252 ⌀ |
|---|---|---|---|---|---|
Why is the sky blue? | STEM | Physics | If you stick your hand out of the car window when it's moving, you can feel the air pushing against your hand. But what if you're just standing in your room? Does that mean the air isn't there? No...it just means that you can't FEEL the air unless it bounces off something. Light works kinda the same. Most of the time w... | Elementary | null |
Why is the sky blue? | STEM | Physics | When sunlight reaches Earth's atmosphere, it is scattered in all directions by all the gases and particles in the air. Blue is scattered by air molecules more than other colors because it travels as shorter, smaller waves. This is why we see a blue sky most of the time. | High School | https://spaceplace.nasa.gov/blue-sky/en/ |
Why is the sky blue? | STEM | Physics | The blue colour of the sky is nowadays usually explained by Rayleigh scattering, an explanation that is, however, not entirely correct. In his 1953 publication entitled "Explanation of the Brightness and Color of the Sky, Particularly the Twilight Sky", Edward Olson Hulburt (1890–1982) demonstrated that for specific il... | PhD | https://acp.copernicus.org/articles/23/14829/2023/ |
Why do music trends change over time? | Non-STEM | Music History | Innovation. If you sound nothing like anyone else, you're one of a kind, which in art equals popularity. Soon after, everyone tries to copy you, and that's how genres are created. | Elementary | null |
Why do music trends change over time? | Non-STEM | Music History | Technological developments played a vital role in bringing popular music to people's homes. The invention of the phonograph and gramophone in the late 19th century enabled the reproduction and mass distribution of sound recordings for the first time. The invention of the reel-to-reel tape recorder and the development o... | High School | null |
Why do music trends change over time? | Non-STEM | Music History | It was found that fame of the artist, ties with other media and compilation albums featuring several artists prolonged the hit's chart period. A survival analysis was also used in a study, which measured the statistical correlations of the period that an album stayed in the weekly hit charts in the US music market. The... | PhD | null |
Why do organisms require oxygen for survival? | STEM | Biology | Most living things need oxygen to survive. Oxygen helps organisms grow, reproduce, and turn food into energy. Humans get the oxygen they need by breathing through their nose and mouth into their lungs. Oxygen gives our cells the ability to break down food in order to get the energy we need to survive. Although other an... | Elementary | null |
Why do organisms require oxygen for survival? | STEM | Biology | Aerobic respiration, which takes place in the presence of oxygen, evolved after oxygen was added to Earth’s atmosphere. A major advantage of aerobic respiration is the amount of energy it releases. Without oxygen, organisms can split glucose into just two molecules of pyruvate. This releases only enough energy to make ... | High School | null |
Why do organisms require oxygen for survival? | STEM | Biology | Gaseous oxygen is essential for all aerobic animals, without which mitochondrial respiration and oxidative phosphorylation cannot take place. | PhD | null |
Why do we dream? | Non-STEM | Psychology | When we go to sleep at night, it can look like our bodies and our brains are turning off. But while the rest of your body is resting and recharging, your brain is actually working pretty hard -- and showing you dreams, like a movie going on inside your head! When you're dreaming, some parts of your brain are switched o... | Elementary | null |
Why do we dream? | Non-STEM | Psychology | Dreams provide a "psychic safety valve"—expressing otherwise unacceptable feelings; contain manifest (remembered) content and a deeper layer of latent content—a hidden meaning. stories our brain tells us while we are sleeping. A collection of clips, image, feelings, & memories that occur during our REM sleep. | High School | null |
Why do we dream? | Non-STEM | Psychology | J. Allan Hobson’s definition that dreaming is mental activity during sleep with most of the following features present – hallucinations, delusions, narrative structure, hyperemotionality, and bizarreness – emphasizes the qualitative features of dream content. Antti Revonsuo recently suggested that instead of strict def... | PhD | null |
Why do we use binary code in computer systems? | STEM | Computer Science | Binary has two states: off and on. If computers were to use the decimal system, there would be 10 states instead and they would have to work a lot harder to process them all. Binary is easier for computers to process, and it also takes up less space. | Elementary | https://edu.gcfglobal.org/en/computer-science/binary/1/ |
Why do we use binary code in computer systems? | STEM | Computer Science | The binary number system is the base of all computing systems and operations. It enables devices to store, access and manipulate all types of information directed to and from the CPU or memory. The binary schema of digital 1s and 0s offers a simple and elegant way for computers to work. It also offers an efficient way ... | High School | https://www.techtarget.com/whatis/definition/binary |
Why do we use binary code in computer systems? | STEM | Computer Science | Binary encoding in digital systems is fundamentally aligned with the bistable nature of CMOS transistors, which serve as the primary switching elements in integrated circuits. The inherent two-state operation—where each transistor represents a logical high or low voltage corresponding to binary 1 or 0—facilitates highl... | PhD | https://ieeexplore.ieee.org/document/52187 |
Why is iodine added to salt? | STEM | Health | Iodine is used by the thyroid gland in your throat to make thyroid hormones. These hormones control your metabolic rate (the rate at which your body uses energy when it is resting). They also help your brain and body grow and develop.
If there isn’t enough thyroid hormone circulating in your blood, your brain sends a ... | Elementary | https://www.betterhealth.vic.gov.au/health/healthyliving/iodine |
Why is iodine added to salt? | STEM | Health | Iodine is an element found mainly in seawater and in soil close to the sea. The human body needs iodine to make thyroid hormone. During fetal development, infancy, and childhood, thyroid hormone is essential for the brain and nervous system to develop normally. Too little iodine, and thus too little thyroid hormone, ca... | High School | https://www.health.harvard.edu/heart-health/cut-salt-it-wont-affect-your-iodine-intake |
Why is iodine added to salt? | STEM | Health | Adequate levels of iodine, a trace element variably distributed on the earth and found mostly in the soil and water of coastal areas, are required for the synthesis of the thyroid hormones, thyroxine (T4) and triiodothyronine (T3), which play key roles in the metabolic processes of vertebrate life. The major concerns r... | PhD | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3509517/ |
Why is the Amazon rainforest important? | STEM | Environmental Science | The Amazon is of vital importance because people around the world, as well as locally, depend on the rainforest. Not just for food, water, wood and medicines, but to help stabilise the climate—150-200 billion tons of carbon is stored in the Amazon rainforest. | Elementary | https://www.wwf.org.uk/where-we-work/amazon#:~:text=The%20Amazon%20is%20of%20vital,stored%20in%20the%20Amazon%20rainforest. |
Why is the Amazon rainforest important? | STEM | Environmental Science | The Amazon rainforest region functions as a carbon sink through the process of photosynthesis. During photosynthesis, trees and other vegetation absorb CO2 from the atmosphere and use it to produce energy, storing the carbon in their roots, branches, leaves, and trunks. This process not only removes CO2 from the atmosp... | High School | https://greenly.earth/en-us/blog/ecology-news/the-complex-role-of-the-amazon-rainforest |
Why is the Amazon rainforest important? | STEM | Environmental Science | A large fraction of precipitation in the Amazon basin is recycled, and, therefore, simulations of Amazon deforestation typically generate ≈20–30% reductions in precipitation (78), lengthening of the dry season, and increases in summer temperatures (79) that would make it difficult for the forest to reestablish, and sug... | PhD | https://www.pnas.org/doi/full/10.1073/pnas.0705414105 |
Why isn't Pluto considered a planet anymore? | STEM | Astronomy | So, in the 19th century, we discovered a new planet between Mars and Jupiter called Ceres. However, over time, we started discovering a ton of other, similar objects, around the same orbit. We discovered so many that we realized it didn't make any sense to call them all planets so we classified them differently. Pluto ... | Elementary | https://www.reddit.com/r/explainlikeimfive/comments/10rwbal/eli5_why_is_pluto_not_a_planet/ |
Why isn't Pluto considered a planet anymore? | STEM | Astronomy | Pluto is now classified as a dwarf planet because, while it is large enough to have become spherical, it is not big enough to exert its orbital dominance and clear the neighborhood surrounding its orbit. | High School | https://www.britannica.com/story/why-is-pluto-no-longer-a-planet#:~:text=Pluto%20is%20now%20classified%20as,the%20neighborhood%20surrounding%20its%20orbit. |
Why isn't Pluto considered a planet anymore? | STEM | Astronomy | For a long time, no one searched for other TNOs as it was generally believed that Pluto, which up to August 2006 was classified as a planet, was the only major object beyond Neptune. Only after the 1992 discovery of a second TNO, 15760 Albion, did systematic searches for further such objects begin. A broad strip of the... | PhD | https://en.wikipedia.org/wiki/Trans-Neptunian_object#Subsequent_discoveries |
Why can't we divide by zero in mathematics? | STEM | Mathematics | Okay so say you have 10 apples. You can put those apples into 10, 5, 2, or 1 group/s quite easily. You could even put them into 4 groups by splitting 2 of the apples in half. How many apples would be in those 0 groups? How do you put 10 apples into 0 groups? The answer is that you cannot physically put those 10 apples ... | Elementary | https://www.reddit.com/r/explainlikeimfive/comments/62dytm/eli5_why_cant_you_divide_by_zero/ |
Why can't we divide by zero in mathematics? | STEM | Mathematics | It’s not that it’s “impossible” to divide by 0, it’s simply not defined. Intuitively, this means that if we were to take a number n and say that n÷0=q, then the quotient q, whatever it was, would not make sense based on the meaning and properties of division. | High School | https://qr.ae/p25eNI |
Why can't we divide by zero in mathematics? | STEM | Mathematics | Localization of every commutative ring at zero is the trivial ring, where 0=1. so nontrivial commutative rings do not have inverses at zero, and thus division by zero is undefined for nontrivial commutative rings. | PhD | https://en.wikipedia.org/wiki/Division_by_zero#Distribution_theory |
Why do geese fly in a 'V' formation? | STEM | Biology | The bird breaking the air creates a mini updraft, which the bird behind it can ride. The bird in front does most of the heavy lifting, and the birds at the end of the V get the least amount of help, so the flock regularly rotates positions to ensure that each bird has equal time 'resting' and equal time 'working'. | Elementary | https://www.reddit.com/r/explainlikeimfive/comments/3yc4w8/eli5_why_do_geese_fly_in_the_v_formation/ |
Why do geese fly in a 'V' formation? | STEM | Biology | Geese fly in a V formation for several reasons. Firstly, this arrangement allows for improved energy conservation. As each goose flaps its wings, it creates an uplift for the one following it, thereby reducing the overall energy expenditure of the flock. Secondly, the V-shaped formation enhances communication and coord... | High School | https://www.tigerhills.ca/a/why-do-geese-fly-in-a-v-understanding-the-flight-patterns-and-behaviors.html |
Why do geese fly in a 'V' formation? | STEM | Biology | An aerodynamic advantage resulting from formation flying has been discussed by several authors. Lissaman and Schollenbergcr (1970) proposed that in one type of line formation,the V, an aero-dynamic advantage is gained by an individual bird by maintaining a particular wing tip-to-wingtip distance, and by angular positio... | PhD | https://sora.unm.edu/sites/default/files/journals/jfo/v045n02/p0160-p0169.pdf |
Why are trans fats bad for health? | STEM | Health | Trans fat is considered the worst type of fat to eat. Unlike other dietary fats, trans fats — also called trans-fatty acids — raise "bad" cholesterol and also lowers "good" cholesterol. A diet laden with trans fats increases the risk of heart disease, the leading killer of adults. | Elementary | https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/in-depth/trans-fat/art-20046114 |
Why are trans fats bad for health? | STEM | Health | Trans fats raise your bad (LDL) cholesterol levels and lower your good (HDL) cholesterol levels. Eating trans fats increases your risk of developing heart disease and stroke. It’s also associated with a higher risk of developing type 2 diabetes. | High School | https://www.heart.org/en/healthy-living/healthy-eating/eat-smart/fats/trans-fat |
Why are trans fats bad for health? | STEM | Health | Trans fatty acids raise plasma low-density lipoprotein (LDL) cholesterol levels in volunteers when exchanged for cis unsaturated fatty acids in the diet. In addition, trans fatty acids may lower high-density lipoprotein (HDL) cholesterol levels and raise triglyceride and lipoprotein(a) levels in plasma. Trans and cis u... | PhD | https://pubmed.ncbi.nlm.nih.gov/8527230/ |
Why do we adjust for degrees of freedom in variance and standard deviation? | STEM | Mathematics | Degrees of freedom are the number of independent variables that can be estimated in a statistical analysis and tell you how many items can be randomly selected before constraints must be put in place.
Within a data set, some initial numbers can be chosen at random. However, if the data set must add up to a specific su... | Elementary | https://www.investopedia.com/terms/d/degrees-of-freedom.asp |
Why do we adjust for degrees of freedom in variance and standard deviation? | STEM | Mathematics | Degrees of freedom are the number of independent values that a statistical analysis can estimate. You can also think of it as the number of values that are free to vary as you estimate parameters.
Degrees of freedom encompasses the notion that the amount of independent information you have limits the number of paramet... | High School | https://qr.ae/p25eSh |
Why do we adjust for degrees of freedom in variance and standard deviation? | STEM | Mathematics | Degrees of freedom is a parameter that is dependent upon sample size, which is used to calculate the probability distributions for certain statistical models. Degrees of freedom may be considered a measure of parsimony, as it is a measure of the number of observations available to vary, to estimate additional paramete... | PhD | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2405942/ |
Why do we enjoy horror movies or stories? | non-STEM | Psychology | All the same reasons people like sad songs, Halloween, war documentaries, apocalyptic fiction, etc. etc. It’s like any other film genre. Horror movies can be artistic; the performances can be entertaining; the movies can be well-constructed or conceived; they can be relatable or provide personal insight. Etc. | Elementary | https://www.reddit.com/r/explainlikeimfive/comments/jtrt5v/eli5_why_do_people_enjoy_horror_movies/ |
Why do we enjoy horror movies or stories? | non-STEM | Psychology | According to these researchers, stimulation is one of the driving forces behind the consumption of horror. Exposure to terrifying acts like stories of demonic possession or alien infestation can be stimulating both mentally and physically. These experiences can give rise to both negative feelings, such as fear or anxie... | High School | https://carey.jhu.edu/articles/research/why-we-enjoy-horror-science-explains |
Why do we enjoy horror movies or stories? | non-STEM | Psychology | “The horror film occupies in popular culture roughly comparable to that of horror literature. That is to say, it is generally ignored, sometimes acknowledged with bemused tolerance, and viewed with alarm when it irritates authority - rather like a child too spirited to follow the rules that rendition has deemed accepta... | PhD | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6813198/ |
Why do cultures evolve over time? | non-STEM | Sociology | This may happen when the environment changes. It also happens when different groups come into contact with one another. Each group brings new ideas that can cause changes in the other group’s culture. Sometimes conflict happens when different cultures come into contact. Other times the contact is peaceful, and the gro... | Elementary | https://kids.britannica.com/kids/article/culture/399913 |
Why do cultures evolve over time? | non-STEM | Sociology | And just like in genetic evolution, not all cultural change is due to selection. Culture can change due to random chance or population structures such as bottlenecks. This is called cultural drift, analogous to genetic drift. Or migration and mutation can bring new cultural traits into a population, just as it brings i... | High School | https://culturalevolutionsociety.org/about-cultural-evolution/what-is-cultural-evolution/ |
Why do cultures evolve over time? | non-STEM | Sociology | What makes this program evolutionary resists any brief answer, but some relevant factors include the following: researchers in this tradition often examine how cultural inheritance interacts with the forms of inheritance (especially genetic inheritance) studied by mainstream evolutionary theorists; they seek to underst... | PhD | https://plato.stanford.edu/entries/evolution-cultural/ |
Why is voting an important responsibility in democratic nations? | non-STEM | Political Science | If you decide to opt out of the political system by not voting, others will. That means that their preferences and not yours will determine which politicians pass the laws that have power over you. Those laws determine who will gain and lose money and property (taxation, fines, eminent domain, grants, government contra... | Elementary | https://www.reddit.com/r/explainlikeimfive/comments/1efgfo0/eli5_why_it_is_important_to_vote/ |
Why is voting an important responsibility in democratic nations? | non-STEM | Political Science | Voting is morally special in its own right regardless of the fact that citizens may also be bound to discharge other duties of aid. Because governments are powerful entities that distribute and shape access to basic social goods as no other organization does, the mechanism to install them is unique and deserves moral a... | High School | https://academic.oup.com/book/32280/chapter-abstract/268488504?redirectedFrom=fulltext |
Why is voting an important responsibility in democratic nations? | non-STEM | Political Science | Although voting certainly encompasses the notions of self-governance and democratic expression, today's clashes over elections and participation are really about equality. By focusing so much on equality, we gives too short shrift to the power of the foundational importance of voting and democratic participation to res... | PhD | https://uknowledge.uky.edu/cgi/viewcontent.cgi?article=1297&context=law_facpub |
Why is Beethoven's Fifth Symphony popular? | non-STEM | Musicology | The same reason the Mona Lisa is the "best" painting and The Barber of Seville is the "best" opera. Most people are fairly ignorant of the fine arts, and tend to latch on to one token example that has drifted into popular culture to the point it becomes a cliche. | Elementary | https://www.reddit.com/r/explainlikeimfive/comments/1yzrrg/eli5what_made_beethovens_fifth_symphony_so_special/ |
Why is Beethoven's Fifth Symphony popular? | non-STEM | Musicology | There is a reason for all this exposure and inclusion in mainstream culture well beyond the 1808 Vienna premiere: the music itself, all stemming from that iconic four-note opening. Syncopated, catchy, impactful; it’s just so distinctive. | High School | https://www.aco.com.au/news/2023-november/why-is-beethoven-symphony-no-5-so-famous |
Why is Beethoven's Fifth Symphony popular? | non-STEM | Musicology | One of the aspects that makes the Fifth Symphony remarkable is that the “fate motif” is not treated as simply a first theme. Instead, Beethoven put it throughout the entire piece—an obsessive repetition of the motif at different pitch levels, combined with interruptive stops that fight its restless momentum. | PhD | https://www.esm.rochester.edu/beethoven/symphony-no-5/ |
Why do we feel guilt? | non-STEM | Psychology | It's just a type of social pain. You feel guilt when you think you've caused harm to others: this is useful because it generally teaches you to stop hurting others in the same way that pain teaches you to stop hurting yourself. | Elementary | https://www.reddit.com/r/explainlikeimfive/comments/2nt2zn/eli5_why_do_we_feel_guilt_is_this_a_survival/ |
Why do we feel guilt? | non-STEM | Psychology | In a psychological context, guilt is considered the more proactive emotional response to an occurrence or action taken, as opposed to shame. Guilt is tied to empathy, pushing a person to look beyond themselves and consider how their behavior may impact others. Shame centers on the individual and how they feel about beh... | High School | https://study.com/academy/lesson/the-psychology-of-guilt-definition-lesson-quiz.html |
Why do we feel guilt? | non-STEM | Psychology | Guilt has a cognitive component, in that the negative emotion presupposes one’s responsibility for the problematic action or inaction. The attribution of responsibility to one’s own behavior (something that can be changed) is important, insofar as it suggests and motivates different behaviors that can make amends for t... | PhD | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4238306/ |
Why is racism still prevalent? | non-STEM | Sociology | It's normal to want to spend time with people that have the same interests, background, culture and language. It creates a sense of belonging that is really important. The downside is that it can also set up differences between other groups and, over time, this might lead to us to thinking that our group is better than... | Elementary | https://humanrights.gov.au/our-work/education/why-are-people-racist |
Why is racism still prevalent? | non-STEM | Sociology | Essentially- it is human nature to defend the group you align yourself with (can be a sports team, a gender, a race, a career type, etc etc) vs the group you perceive to be a competition (the other team, race, gender, etc). So if someone has a higher degree of emotional insecurity, chemical imbalance, lesser education,... | High School | https://www.reddit.com/r/askpsychology/comments/1b9qd1d/why_are_people_racist/ |
Why is racism still prevalent? | non-STEM | Sociology | Although there have been some remarkable gains in the labor force status of racial minorities, significant disparities remain. African Americans are twice as likely to be unemployed as whites (Hispanics are only marginally so), and the wages of both blacks and Hispanics continue to lag well behind those of whites (auth... | PhD | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2915460/ |
Why is love a universal concept? | non-STEM | Psychology | Some researchers suggest that love is a basic human emotion just like happiness or anger, while others believe that it is a cultural phenomenon that arises partly due to social pressures and expectations. | Elementary | https://www.verywellmind.com/what-is-love-2795343 |
Why is love a universal concept? | non-STEM | Psychology | It’s suggested that areas of the brain, particularly the ventral tegmental area (located in the middle of the brain), responsible for motivation and emotional regulation are associated with maternal and romantic love.
Feelings of love help us form social bonds with others. As social creatures, these natural chemicals d... | High School | https://psychcentral.com/relationships/the-psychology-of-love#what-is-love |
Why is love a universal concept? | non-STEM | Psychology | Defining romantic love has been a challenge for theorists. Researchers have found that people’s conception of romantic love varies across cultures. The fact that romantic love is documented in cross-cultural samples stands in direct contradiction to the popular ideas that romantic love is limited to or the product of W... | PhD | https://core.ac.uk/download/pdf/222806221.pdf |
Why do athletes make more money than other professionals? | non-STEM | Sociology | It's mainly the economics surrounding sports. Sports bring in billions of dollars through ticket sales, broadcasting deals, jersey sales, endorsements, etc. If getting a better player helps the team and leads to more money coming in, teams will pay more to improve the team. | Elementary | https://www.reddit.com/r/explainlikeimfive/comments/1ki4jp/eli5_why_do_athletes_make_significantly_more/ |
Why do athletes make more money than other professionals? | non-STEM | Sociology | Sports is only such a massive and profitable industry because of the enormous global fan bases that love it. If there was not such a high demand for these athletes and their performances, the industry would not be turning over so many figures a year. | High School | https://dailytrojan.com/2023/09/28/why-professional-athletes-are-making-so-much-money/#:~:text=Sports%20is%20only%20such%20a,so%20many%20figures%20a%20year. |
Why do athletes make more money than other professionals? | non-STEM | Sociology | The explanation for the salary differences lies in a 'personal scale of operations' effect in sports compared to teaching and most other jobs. | PhD | https://www.nber.org/system/files/working_papers/w7573/w7573.pdf |
Why are there different seasons? | STEM | Earth Science | The Earth is tilted, and the axis of that tilt moves around during the year. When the north part is pointing towards the sun, the northern hemisphere has summer and the southern hemisphere has winter. When the north part is pointing away from the sun, it's the opposite. When it's pointing off to the side, we have sprin... | Elementary | https://www.reddit.com/r/explainlikeimfive/comments/1p6jme/eli5_seasons_how_and_why_do_they_occur/ |
Why are there different seasons? | STEM | Earth Science | As the earth spins on its axis, producing night and day, it also moves about the sun in an elliptical (elongated circle) orbit that requires about 365 1/4 days to complete. The earth's spin axis is tilted with respect to its orbital plane. This is what causes the seasons. When the earth's axis points towards the sun, i... | High School | https://www.weather.gov/lmk/seasons#:~:text=The%20earth's%20spin%20axis%20is,away%2C%20winter%20can%20be%20expected. |
Why are there different seasons? | STEM | Earth Science | When the Earth is in position A (June 21), the tilt of the axis is exactly towards the sun, causing the sun to appear 23.5 degrees higher than it would be if the axis had no tilt. The "little man" at the North Pole sees the sun at an altitude of 23.5 degrees above the horizon. Since he is turning with the Earth, the su... | PhD | https://scholar.smu.edu/fieldandlab/vol13/iss1/2/ |
Why does DNA have a double helix structure? | STEM | Biology | DNA is made up of small components called nucleotides. A nucleotide is made up of 3 parts: a phosphate group, a sugar, and a base. The base can be 1 of 4 varieties: A, T, C, or G. Simply put, because of their structures, A and T bond nicely with one another and C and G bond nicely as well. As a result, a single strand ... | Elementary | https://www.reddit.com/r/explainlikeimfive/comments/2j67u9/eli5_why_dna_is_a_double_helix/ |
Why does DNA have a double helix structure? | STEM | Biology | The three-dimensional structure of DNA—the double helix—arises from the chemical and structural features of its two polynucleotide chains. Because these two chains are held together by hydrogen bonding between the bases on the different strands, all the bases are on the inside of the double helix, and the sugar-phospha... | High School | https://www.ncbi.nlm.nih.gov/books/NBK26821/ |
Why does DNA have a double helix structure? | STEM | Biology | The stability of double-stranded DNA (dsDNA) at physiological temperature is due to the hydrogen bonding between complementary bases and the stacking between neighboring bases. However, these base-stacking interactions are of the order of magnitude of a few k_B T thermal energy and the thermal fluctuations can lead (ev... | PhD | https://www.sciencedirect.com/science/article/pii/S1571064514000062 |
Why does oil not mix with water? | STEM | Chemistry | You can group substances into 2 types - polar and non-polar. A polar substance has different electric charges on different parts - water, for instance, has slightly negatively charged oxygen on one side and the two positively charged hydrogens on the other. When polar molecules mix, the negative sides of some molecules... | Elementary | https://www.reddit.com/r/explainlikeimfive/comments/1bloyc7/eli5_why_does_water_doesnt_mix_with_oil/ |
Why does oil not mix with water? | STEM | Chemistry | Liquid water is held together by hydrogen bonds. (Liquid water has fewer hydrogen bonds than ice.) Oils and fats not have any polar part and so for them to dissolve in water they would have to break some of water s hydrogen bonds. Water will not do this so the oil is forced to stay separate from the water. | High School | https://web.fscj.edu/Milczanowski/psc/lect/Ch10/slide10.htm |
Why does oil not mix with water? | STEM | Chemistry | The widely accepted model explaining the hydrophobic effect invokes the formation of icelike clathrate hydrate "cages" around nonpolar solute molecules. Water molecules at the surface of these relatively rigid clathrate structures are strongly hydrogen-bonded to one another. The formation of these solvent "cages" expla... | PhD | https://pubs.acs.org/doi/abs/10.1021/ed075p116 |
Why are animals colored in certain ways? | STEM | Biology | Some animals have special colors or markings called protective coloration. These markings protect animals from predators, or animals that will eat them. Some markings are a kind of camouflage, meaning that they help the animal blend in with its surroundings. Others help scare predators away by making the animal appear ... | Elementary | https://kids.britannica.com/kids/article/protective-coloration/353670 |
Why are animals colored in certain ways? | STEM | Biology | Many of these animals hold clues that could help answer the question of why such colorful displays evolved. Research published in 2022 showed that all brightly colored terrestrial vertebrate species can generally be split into two camps. In the descendants of nocturnal animals, color can communicate to predators that t... | High School | https://www.livescience.com/animals/why-are-animals-so-colorful |
Why are animals colored in certain ways? | STEM | Biology | Colours made by animals or by other objects in the environment (such as flowers and fruit) may serve a variety of functions. Humans like colours and therefore naturally want to find functions for them, often imposing our primate colour vision system on a non-primate world. We also forget that, compared to many other an... | PhD | https://cdn.wildapricot.com/255957/resources/Documents/jaic_v5_04.pdf |
Why does acid rain occur? | STEM | Environmental Science | Acid rain is a form of air pollution. When coal and petroleum are burned in automobiles, electric power plants, and factories, they release certain harmful gases into the air. These gases combine with the oxygen and water in the air. When the water in the air comes down as rain, sleet, hail, or snow, it carries with it... | Elementary | https://kids.britannica.com/kids/article/acid-rain/352700 |
Why does acid rain occur? | STEM | Environmental Science | Acid rain results when sulfur dioxide (SO2) and nitrogen oxides (NOX) are emitted into the atmosphere and transported by wind and air currents. The SO2 and NOX react with water, oxygen and other chemicals to form sulfuric and nitric acids. These then mix with water and other materials before falling to the ground. | High School | https://www.epa.gov/acidrain/what-acid-rain |
Why does acid rain occur? | STEM | Environmental Science | The sources of acidity in rain can come from anthropogenic or natural activities. Even so, anthropogenic sources are the main contributors of acid rain in urban area. Anthropogenic activities such as burning of fossil fuels from transportation or industrial activities will release sulphuric acid and nitric acid into th... | PhD | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7511740/ |
Why do we yawn? | STEM | Neuroscience | One is that when we are bored or tired, we just don't breathe as deeply as we usually do. As this theory goes, our bodies take in less oxygen because our breathing has slowed. Therefore, yawning helps us bring more oxygen into the blood and move more carbon dioxide out of the blood.
Yawning, then, would be an involunta... | Elementary | https://kidshealth.org/en/kids/yawn.html |
Why do we yawn? | STEM | Neuroscience | Yawing clearly is associated with sleepiness and boredom. However, almost paradoxically, it is theorized that yawning is not a sign of sleepiness or boredom, but actually a reflex that your brain induces to wake you up or make you more alert. Yawning is associated with some hormones that are released that briefly incre... | High School | https://muschealth.org/medical-services/geriatrics-and-aging/healthy-aging/yawning |
Why do we yawn? | STEM | Neuroscience | Evidence suggests that drowsiness is the most common stimulus of yawn. Boredom occurs when the main source of stimulation in a person's environment is no longer able to sustain their attention. This induces drowsiness by stimulating the sleep generating system. At this moment, the mind has to make an effort to maintain... | PhD | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3678674/ |
Why are black holes black? | STEM | Astronomy | A black hole’s gravity, or attractive force, is so strong that it pulls in anything that gets too close. It can even swallow entire stars. Nothing can move fast enough to escape a black hole’s gravity. This includes light, the fastest thing in the universe. That’s why we can’t see black holes in space—they've gobbled u... | Elementary | https://kids.nationalgeographic.com/space/article/black-holes |
Why are black holes black? | STEM | Astronomy | Black holes don’t emit or reflect light, making them effectively invisible to telescopes. | High School | https://science.nasa.gov/universe/black-holes/ |
Why are black holes black? | STEM | Astronomy | In the case of the most massive stars (maybe only stars more massive than say, 25 or even 50 solar masses), not even neutron degeneracy pressure can stop the collapse of the core. In this case, at least 3 solar masses worth of matter collapses into a single point with infinite density. This point is referred to as a si... | PhD | https://www.e-education.psu.edu/astro801/content/l6_p8.html |
Why is latitude measured in 180 degrees? | STEM | Geography | Longitudes go all the way around the earth, but latitudes all meet at the poles. If your latitudes continued past them, you'd have a latitude that increased moving towards the poles, then increased moving away from the poles on the other side. We could do this, but then we would be double-counting locations on the surf... | Elementary | https://www.reddit.com/r/explainlikeimfive/comments/yoyi66/eli5_why_is_latitude_from_90_to_90_but_longitude/ |
Why is latitude measured in 180 degrees? | STEM | Geography | A cutaway drawing of the Earth demonstrates how latitude is determined. It makes clear that latitude is a measure of the angle between the plane of the equator and lines projected from the center of the Earth. For example, the angle between a line drawn from New Orleans on the 30th line of latitude to the center of the... | High School | https://kids.britannica.com/students/article/latitude-and-longitude/275388#:~:text=Lines%20of%20latitude%20north%20and,or%20simply%2090%C2%B0%20N. |
Why is latitude measured in 180 degrees? | STEM | Geography | Two levels of abstraction are employed in the definitions of latitude and longitude. In the first step the physical surface is modeled by the geoid, a surface which approximates the mean sea level over the oceans and its continuation under the land masses. The second step is to approximate the geoid by a mathematically... | PhD | https://en.wikipedia.org/wiki/Latitude |
Why is water considered a universal solvent? | STEM | Chemistry | Water is made up of tiny things called molecules. Each water molecule is like a magnet - one side pulls on one kind of thing while the other side pulls on the opposite kind of thing. Most things are made up of the two different kind of things. So two water molecules pulling in opposite directions will pull many things ... | Elementary | https://www.reddit.com/r/explainlikeimfive/comments/2hfpe1/eli5_why_is_water_the_universal_solvent/ |
Why is water considered a universal solvent? | STEM | Chemistry | Water is called the "universal solvent" because it is capable of dissolving more substances than any other liquid. This is important to every living thing on earth. It means that wherever water goes, either through the air, the ground, or through our bodies, it takes along valuable chemicals, minerals, and nutrients. | High School | https://www.labxchange.org/library/items/lb:LabXchange:b8e3583f:html:1 |
Why is water considered a universal solvent? | STEM | Chemistry | Water is called the universal solvent because it dissolves a wide variety of substances. Water is polar, so it readily dissolves charged or polar solutes. Water also dissolves some molecules that have nonpolar character, such as aromatics and surfactants. However, water is not a good solvent for nonpolar molecules such... | PhD | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5639468/ |
Why is Neptune blue? | STEM | Astronomy | Its atmosphere is made of hydrogen, helium, and methane. The methane gives Neptune the same blue color as Uranus. | Elementary | https://spaceplace.nasa.gov/all-about-neptune/en/ |
Why is Neptune blue? | STEM | Astronomy | Neptune's atmosphere is made up of hydrogen, helium and methane. The methane in Neptune's upper atmosphere absorbs the red light from the sun but reflects the blue light from the Sun back into space. This is why Neptune appears blue. | High School | https://coolcosmos.ipac.caltech.edu/ask/138-why-is-neptune-blue- |
Why is Neptune blue? | STEM | Astronomy | We now know this blueness comes from a combination of this higher abundance of gaseous methane, which has strong absorption bands in the infrared and red portion of the visible spectrum, and enhanced Rayleigh‐scattering from atmospheres that have low abundances of aerosols. | PhD | https://pmc.ncbi.nlm.nih.gov/articles/PMC9286428/ |
Why is gravity important? | STEM | Physics | Gravity is the force that pulls things toward the center of the Earth, or towards the center of other physical bodies that have mass (for example, other planets, and even the sun!). Gravity is very important: it's why we have weight, why we naturally stay on the ground, why planes need to generate lift to get up into t... | Elementary | https://howthingsfly.si.edu/ask-an-explainer/why-gravity-important |
Why is gravity important? | STEM | Physics | Gravity is the most significant interaction between objects at the macroscopic scale, and it determines the motion of planets, stars, galaxies, and even light. | High School | https://en.wikipedia.org/wiki/Gravity |
Why is gravity important? | STEM | Physics | Gravity is a fundamental interaction that permeates throughout our Universe. On Earth, gravity gives weight to physical objects, and has been a constant presence throughout terrestrial biological evolution. Thus, gravity has shaped all biological functions, some examples include the growth of plants (e.g., gravitropism... | PhD | https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2023.1199175/full |
Why do we have day and night? | STEM | Astronomy | We get day and night because the Earth rotates on an imaginary line called an axis. During daytime, your part of the Earth is facing the sun. As the Earth rotates you move away from the sun until eventually, the sun is no longer visible. For you, this is now nighttime, but for the other side of the planet, day has just... | Elementary | https://www.twinkl.com/teaching-wiki/day-and-night |
Why do we have day and night? | STEM | Astronomy | The Earth orbits the sun once every 365 days and rotates about its axis once every 24 hours. Day and night are due to the Earth rotating on its axis, not its orbiting around the sun. The term ‘one day’ is determined by the time the Earth takes to rotate once on its axis and includes both day time and night time. | High School | https://www.education.vic.gov.au/school/teachers/teachingresources/discipline/science/continuum/Pages/daynight.aspx |
Why do we have day and night? | STEM | Astronomy | The spins of the terrestrial planets likely arose as the planets formed by the accretion of planetesimals. Depending on the masses of the impactors, the planet's final spin can either be imparted by many small bodies (ordered accretion), in which case the spin is determined by the mean angular momentum of the impactors... | PhD | https://go.gale.com/ps/i.do?id=GALE%7CA13362227&sid=googleScholar&v=2.1&it=r&linkaccess=abs&issn=00368075&p=AONE&sw=w&userGroupName=anon%7Eb93ac799&aty=open-web-entry |
Why is the ozone hole a concern? | STEM | Environmental Science | Ozone is a natural part of Earth’s upper atmosphere. This part of the atmosphere, about 15 miles (24 kilometers) above the surface, is called the ozone layer. It protects people by absorbing harmful rays from the sun. If they reach Earth, these rays can cause skin cancer, eye diseases, and other health problems.
Som... | Elementary | https://kids.britannica.com/kids/article/ozone/353588 |
Why is the ozone hole a concern? | STEM | Environmental Science | Ozone depletion can cause increased amounts of UV radiation to reach the Earth which can lead to more cases of skin cancer, cataracts, and impaired immune systems. Too much exposure to UV is believed to be contributing to the increase in melanoma, the most fatal of all skin cancers. | High School | https://www.tn.gov/health/cedep/environmental/environmental-health-topics/eht/ozone.html |
Why is the ozone hole a concern? | STEM | Environmental Science | The weak Antarctic vortex in 2019 favoured extreme weather and wildfires in Australia.
The unusual warming of the Antarctic stratosphere in September 2019 favoured the extremely dry conditions observed during the summer of 2019/20 in the Southern Hemisphere [2] that contributed to the devastating “2019/2020 Black Summ... | PhD | https://pmc.ncbi.nlm.nih.gov/articles/PMC8860140/ |
Why are some bacteria beneficial? | STEM | Health Science | Some bacteria are good for our bodies — they help keep things in balance. Good bacteria live in our intestines and help us use the nutrients in the food we eat and make waste from what's left over. We couldn't make the most of a healthy meal without these important helper germs! | Elementary | https://kidshealth.org/en/kids/germs.html |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.