Which planet takes the longest to orbit the Sun?
Neptune — one of its years is 165 of ours.
Science
Chemistry, physics, biology and the laws that run the natural world — from the elements to the far planets.
218 questions · tap a question to reveal the answer
Which gas do plants take in from the air?
Carbon dioxide — they give the oxygen back.
What is the main gas in the air we breathe?
Nitrogen — about four fifths of every breath.
Which organ filters waste out of your blood?
The kidneys — about 180 litres filtered a day.
At what temperature does water freeze, in Celsius?
0 degrees — Zero - the scale was built around it.
Which is the largest planet in the Solar System?
Jupiter — it could swallow all the others together.
Which sea creature has blue blood?
The horseshoe crab — copper carries its oxygen, not iron.
How long does light from the Sun take to reach Earth?
About eight minutes — you always see the Sun slightly late.
What is the smallest unit of matter that keeps an element's identity?
The atom — split it and you have a different element.
What makes the sky look blue?
Sunlight scattering off the air — Scattering - air deflects blue light far more than red.
Which is the longest bone in the human body?
The thigh bone — The femur - about a quarter of your height.
What is the largest organ of the human body?
The skin — about two square metres of it.
Which planet is famous for its rings?
Saturn — though all four giant planets have some.
What do you call a scientist who studies fossils?
A palaeontologist — archaeologists dig up people.
Which animal produces the loudest sound?
The blue whale — louder than a jet engine, and it carries for miles.
Which is the smallest planet in the Solar System?
Mercury — barely larger than our Moon.
What is the centre of an atom called?
The nucleus — and it is almost all of the mass.
What is the closest star to Earth?
The Sun — a perfectly ordinary star seen very close up.
What is the largest living structure on Earth?
The Great Barrier Reef — visible from orbit, and built by animals.
Where is the largest volcano in the Solar System?
Mars — Olympus Mons, roughly the size of France.
What do we call the boundary a black hole's light cannot escape?
The event horizon — the point of no return.
What is the powerhouse of the cell?
The mitochondrion — and it carries its own DNA.
Which is the smallest bone in the human body?
The stirrup, in the ear — The stirrup - about three millimetres, and it carries sound.
What do we call rain that has become acidic from pollution?
Acid rain — mostly from burning coal.
Which gas makes bread rise?
Carbon dioxide — breathed out by yeast.
Which planet has the shortest day?
Jupiter — it turns right round in about ten hours.
Which colour absorbs the most heat?
Black — it absorbs nearly all the light that lands on it.
Which part of the eye controls how much light gets in?
The iris — the coloured ring that opens and closes.
Which is the hottest planet in the Solar System?
Venus — its atmosphere traps heat, though Mercury is nearer the Sun.
Which element do we breathe in to stay alive?
Oxygen — about a fifth of the air.
What does a light year measure?
Distance — how far light travels in a year.
What is the name of our planet's only natural satellite?
The Moon
Which planet is known as the Red Planet?
Mars — colored by iron oxide dust.
Which little insect makes light at night?
Firefly — glowing to attract mates.
What do you call a scientist who studies dinosaurs?
Paleontologist — A paleontologist.
Which bird is a symbol of peace?
Dove — often with an olive branch.
Which planet is closest to the Sun?
Mercury
Which animal is the symbol of the World Wide Fund for Nature (WWF)?
Panda — The giant panda.
How many sides does a hexagon have?
Six — like a honeycomb cell.
Which planet would float, given a big enough bath?
Saturn — it is less dense than water.
Which element is added to iron to make steel?
Carbon — and only about one per cent of it.
Which city had the first electric traffic light?
Cleveland — Ohio, in 1914.
Which of these can a light microscope not show you?
A virus — far too small for light, and needs an electron beam.
What makes water behave so unlike other liquids?
Its molecules stick together — Hydrogen bonds - which is why it climbs, beads, and expands when frozen.
Which non-stick material was discovered by accident?
Teflon — found as a residue in a gas cylinder that should have been empty.
Which reptile's sex is set by nest temperature, not genes?
The crocodile — Crocodiles and many turtles - the temperature of the nest decides.
Which was the first animal to orbit the Earth?
A dog — Laika, in Sputnik 2 in 1957 - and she was never coming back.
Why does a cut onion make you cry but a whole one does not?
Cutting releases a gas that reaches your eyes — Cutting breaks cells that mix two chemicals into an irritating gas.
Why does hot water sometimes freeze faster than cold?
It is disputed and still not settled — The Mpemba effect - reported for centuries, still argued over.
Why is the sky dark at night if the universe is full of stars?
The universe has a finite age, so not all light has arrived — Olbers' paradox - light from the furthest stars has not reached us.
Why is there a leap second added to clocks now and then?
The Earth's spin is uneven and slowly slowing — Atomic time is steadier than the planet, so clocks wait for it.
Why is a day on Venus longer than its year?
It spins extremely slowly — 243 Earth days to spin, 225 to orbit.
Why does the Moon always show us the same face?
It turns once per orbit, locked by Earth's pull — Tidal locking - it rotates exactly once per orbit.
Why does a wet stone look darker than a dry one?
Water makes light bounce back into the surface — Light is reflected back down into the stone instead of escaping.
Why can you hear a distant train through the rail before through the air?
Sound travels much faster through steel — Sound moves roughly fifteen times faster in steel than in air.
Why does a rainbow always appear opposite the Sun?
Light bounces back out of raindrops towards you — Light enters a drop, reflects, and leaves at about 42 degrees.
Why does hot metal glow red before it glows white?
Hotter things emit more of the shorter colours — The hotter it gets the bluer it adds, and red plus everything looks white.
Why does a lightning flash come before the thunder?
Light travels far faster than sound — Both start together; the sound takes about three seconds a kilometre.
What gas do humans need to breathe to live?
Oxygen — about 21 percent of the air.
Which planet is famous for its Great Red Spot?
Jupiter — the spot is a giant storm.
Which planet is shrinking as its core cools?
Mercury — its crust has wrinkled into cliffs hundreds of km long.
Which famous scientist developed the theory of gravity after seeing an apple fall?
Isaac Newton — in the 1600s.
Which organ pumps blood around the body?
The heart — about 100,000 beats a day.
What force keeps us on the ground?
Gravity
Which planet spins on its side?
Uranus — tilted about 98 degrees.
What is the chemical symbol for gold?
Au — from the Latin aurum.
How long does Earth take to orbit the Sun?
One year — about 365.25 days.
Which instrument measures temperature?
Thermometer — A thermometer.
Which planet is called Earth's twin because of its size?
Venus — similar size, wildly hotter.
Which metal is liquid at room temperature?
Mercury — once called quicksilver.
What do we call a scientist who studies the stars?
Astronomer — An astronomer.
What does kneading bread dough actually do?
Builds a gluten network — It links proteins into an elastic mesh that traps gas.
What is the hardest natural substance?
Diamond — crystallized carbon.
Which planet has the most moons discovered so far?
Saturn — with well over 100 confirmed.
Why does breathing pure nitrogen kill without any warning?
The urge to breathe tracks CO2, not oxygen — You only feel suffocation from carbon dioxide building up.
What do you call it when the Moon blocks the Sun?
A solar eclipse
Which planet takes about 88 Earth days to orbit the Sun?
Mercury — the fastest orbiter.
Why is Earth the only planet not named after a god?
Nobody saw it as a planet — For most of history it was not a planet at all - just the ground.
What is the fastest muscle movement in the human body?
Blinking — about a tenth of a second.
What is the name of the galaxy we live in?
The Milky Way
Which planet spins in the opposite direction to the others?
Venus — its sun rises in the west.
Where does most of a tree's mass come from?
The air — Carbon pulled out of the air - a tree is mostly built from gas.
Which planet is the windiest in the solar system?
Neptune — winds over 2,000 km/h.
What does DNA carry?
Genetic instructions — for living things.
Which organ can regrow after most of it is removed?
The liver — it regenerates to full size from a fraction.
What is the chemical symbol for iron?
Fe — from the Latin ferrum.
Which planet's day is longer than its year?
Venus — it spins that slowly.
What do restriction enzymes look for in DNA?
Palindromic sequences — Palindromes - which is what made genetic engineering possible.
What is the largest moon of Saturn?
Titan — bigger than the planet Mercury.
Which planet is named after the Roman god of war?
Mars
What is the main gas in a helium balloon that makes it float?
Helium — lighter than air.
Which planet was demoted to dwarf planet in 2006?
Pluto
Which human blood type is the universal donor?
O negative
What is the chemical formula for table salt?
NaCl — sodium chloride.
Why do fawns have spots?
Dappled light camouflage — They break up the outline in dappled woodland light.
How does a hummingbird survive the night?
It enters torpor — Body temperature falls to near the air's - it hibernates until dawn.
Which scientist proposed the three laws of motion?
Isaac Newton — in 1687.
Which element has the chemical symbol K?
Potassium — from the Latin kalium.
What is the SI unit of force?
Newton
Which is the only metal that is magnetic at room temperature among these?
Iron — with nickel and cobalt in the club.
Which planet's moons are mostly named after Shakespeare characters?
Uranus — Titania, Oberon, Miranda.
Which is the rarest blood type among these?
AB negative — under 1 percent of people.
What does the liver actually do?
Hundreds of different jobs — Over 500 known functions - it is the body's chemical works.
How far away is the nearest star after the Sun?
About 4 light years — Proxima Centauri, roughly 4.2 light years - so we see it 4 years late.
Which chemical element makes up most of the Sun?
Hydrogen — about three quarters of it.
Which organ produces insulin?
The pancreas
What is the hardest working muscle in the body?
The heart — it never rests.
Which bone protects the brain?
The skull
What is the chemical symbol for silver?
Ag — from the Latin argentum.
Which famous scientist was born the year Galileo died?
Isaac Newton — Newton, in 1642.
What are the smallest blood vessels called?
Capillaries
Which gas gives fizzy drinks their bubbles?
Carbon dioxide
Why does Saturn have a hexagon and no other planet does?
A standing wave in a jet stream — Spin a fluid fast enough with a faster band inside it and polygons form.
Which metal has the highest melting point?
Tungsten — about 3,422 Celsius.
Which scientist first described natural selection alongside Darwin?
Alfred Russel Wallace — Wallace — their papers were read together in 1858.
What is the name of the protein that carries oxygen in blood?
Hemoglobin — in red blood cells.
What was the first element created after the Big Bang?
Hydrogen — the simplest atom.
Which planet's year lasts about 12 Earth years?
Jupiter
Which element has the chemical symbol W?
Tungsten — from its German name Wolfram.
Which planet's largest moon is bigger than Mercury?
Jupiter — Ganymede outgrows Mercury.
Which scientist discovered radioactivity in uranium?
Henri Becquerel — Becquerel, in 1896.
What is the second most abundant element in Earth's crust?
Silicon — oxygen is first.
Which planet did Galileo draw twice without realising?
Neptune — in 1612 - he even noted it had moved, and let it go.
Which hormone controls blood sugar?
Insulin — from the pancreas.
What is the chemical symbol for lead?
Pb — from the Latin plumbum.
Which planet's atmosphere is mostly carbon dioxide with sulfuric acid clouds?
Venus — hot enough to melt lead.
What does the acronym LASER stand for, in part?
Light Amplification — by Stimulated Emission of Radiation.
What is the largest cell in the human body?
The egg cell — visible to the naked eye.
What is the medical term for high blood pressure?
Hypertension
What is the brightest star in the night sky?
Sirius — the Dog Star.
What is the chemical name for laughing gas?
Nitrous oxide — N2O.
Which particle carries a negative charge?
Electron
Which scientist coined the term 'cell' after looking at cork?
Robert Hooke — Hooke, in 1665.
What is the largest muscle in the human body?
Gluteus maximus
Which chemical element is named after the Sun?
Helium — from helios, found in the Sun first.
Why is horseshoe crab blood so valuable?
It detects bacterial contamination — It reacts to bacterial toxins at parts per trillion - it tests every injectable drug.
How does an albatross fly for hours without flapping?
It rides wind gradients over waves — Dynamic soaring - harvesting energy from the difference in wind speed.
Which gas is used in most bright street signs?
Neon — hence 'neon signs'.
What is the chemical symbol for tin?
Sn — from the Latin stannum.
Which element is a liquid nonmetal at room temperature?
Bromine — the only one.
Which moon of Jupiter is the most volcanically active body in the solar system?
Io — squeezed by Jupiter's gravity.
What is the rarest naturally occurring element in Earth's crust?
Astatine — under a gram exists at any time.
Which scientist proposed continental drift in 1912?
Alfred Wegener — Wegener — vindicated decades later.
Which planet's moon Triton orbits backwards?
Neptune — Triton was likely captured.
What is the largest volcano on Earth by volume?
Mauna Loa — in Hawaii.
What happens to time at a black hole's edge, seen from outside?
It appears to stop — An infalling object appears to freeze and fade, and never quite crosses.
What is the chemical symbol for antimony?
Sb — from the Latin stibium.
Which blood cells fight infection?
White blood cells
Which chemical element's symbol is Hg?
Mercury — from hydrargyrum — water-silver.
Which nation's air force fought the Battle of Britain against the Luftwaffe?
The RAF — Britain's Royal Air Force, 1940.
Which scientist's laws describe planetary orbits as ellipses?
Johannes Kepler — Kepler, using Brahe's data.
Which gas gives Neptune and Uranus their blue color?
Methane — it absorbs red light.
Which unit measures the frequency of sound waves?
Hertz — cycles per second.
Which element has the chemical symbol Na?
Sodium — from the Latin natrium.
Which element has the highest boiling point of all?
Rhenium — around 5,600 Celsius, edging tungsten.
Which astronomer first measured the distance to another galaxy?
Edwin Hubble — Hubble, using Cepheid stars in Andromeda.
What is the name of the cell's energy currency molecule?
ATP — adenosine triphosphate.
What is the heaviest naturally occurring element by atomic number found in more than trace amounts?
Uranium — element 92.
What is the name of the effect where light bends around massive objects?
Gravitational lensing — predicted by Einstein.
What is the term for a star's brightness as seen from Earth?
Apparent magnitude
Which acid is found in nettles and ant stings?
Formic acid — formica is Latin for ant.
Why do the Taj Mahal's minarets lean outwards?
So they fall away from the tomb — Deliberate - an earthquake would drop them clear of the mausoleum.
What is the name for the point in orbit closest to the Sun?
Perihelion
Which is the only rock regularly eaten by humans?
Salt — halite, a true mineral rock.
What does the Drake equation estimate?
Communicating alien civilizations — The number of detectable civilizations in our galaxy.
Which particle has the same mass as an electron but positive charge?
The positron — antimatter's electron.
Why does the pole star change over millennia?
Earth's axis wobbles — Precession - Vega was the pole star 14,000 years ago and will be again.
What is the name of the deep-ocean zone with no light at all?
The abyssal zone — below 4,000 m.
Who proved that light behaves as electromagnetic waves?
James Clerk Maxwell — Maxwell, with his equations of 1865.
What is the term for an animal that maintains constant body temperature?
Endotherm — An endotherm — warm-blooded.
Who first split the atom's nucleus in 1917-1919 experiments?
Ernest Rutherford — Rutherford, transmuting nitrogen.
What is the brightest star in the constellation Lyra?
Vega — part of the Summer Triangle.
Which metal's name comes from the Latin for Cyprus?
Copper — cuprum, the island's metal.
Which Dutch scientist first saw bacteria through a microscope?
Antonie van Leeuwenhoek — Van Leeuwenhoek, in the 1670s.
Which gas was used to fill the Hindenburg?
Hydrogen — with catastrophic results in 1937.
Why can Rh-null donors never receive most blood?
They lack every Rh antigen — Golden blood gives to almost anyone and can accept from almost nobody.
What is the densest naturally occurring element?
Osmium — about 22.6 g/cm3.
Which organ of a sperm whale inspired the name 'spermaceti'?
Its head organ — The spermaceti organ in its head — once prized oil.
What is the name of the process by which stars fuse hydrogen via carbon catalysis?
The CNO cycle — dominant in heavier stars.
Which enzyme unwinds DNA during replication?
Helicase
What is the fastest spinning type of star?
A millisecond pulsar — Millisecond pulsars — hundreds of turns a second.
Which metal is extracted from the ore bauxite?
Aluminium
What is the brightest star in the constellation Orion?
Rigel — slightly outshining Betelgeuse.
Which acid gives vinegar its taste?
Acetic acid
What did Dirac do with the equation's 'nonsense' solutions?
Took them seriously — Negative-energy solutions looked absurd; he proposed they were real particles.
What is the largest known structure in the universe?
The Hercules-Corona Borealis Great Wall — A wall of galaxies about 10 billion light-years across.
Which laboratory glassware is named after a German chemist?
The Erlenmeyer flask
Which planet's rings were discovered from Earth in 1977 by stellar occultation?
Uranus — the star blinked before and after.
Which element, number 43, was the first to be artificially produced?
Technetium — 'artificial' in Greek.
Technetium is a chemical element; it has symbol Tc and atomic number 43. It is the lightest element whose isotopes are all radioactive. Technetium is one of only two radioactive elements both preceded and succeeded in the periodic table by elements with stable forms, the other being promethium. All available technetium is produced as a…
Wikipedia · TechnetiumWhat is the Chandrasekhar limit approximately?
1.4 solar masses — About 1.4 solar masses — the white dwarf ceiling.
The Chandrasekhar limit is the maximum mass of a stable white dwarf star. These stars resist gravitational collapse primarily through electron degeneracy pressure, compared to main sequence stars, which resist collapse through thermal pressure. The Chandrasekhar limit is the mass above which electron degeneracy pressure in the star's…
Wikipedia · Chandrasekhar limitWhich deep-Earth mineral makes up most of the lower mantle?
Bridgmanite — the planet's most abundant mineral.
Silicate perovskite is either (Mg,Fe)SiO3 or CaSiO3 when arranged in a perovskite structure. Silicate perovskites are not stable at Earth's surface, and mainly exist in the lower part of Earth's mantle, between about 670 and 2,700 km depth. They are thought to form the main mineral phases of the lower mantle, together with ferropericlase.
Wikipedia · Silicate perovskiteWhat is the term for the 26,000-year cycle completed by the pole star's change?
The Great Year — of axial precession.
The term Great Year has multiple meanings. In scientific astronomy, it refers to the time required for the equinoxes to complete one full cycle around the ecliptic, a period of approximately 25,800 years. According to Ptolemy, his teacher Hipparchus discovered this phenomenon by comparing the position of the vernal equinox against the…
Wikipedia · Great YearWhich molecule's double-helix X-ray image was Photo 51?
DNA — Rosalind Franklin's crucial image.
Deoxyribonucleic acid is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of all known organisms and many viruses. DNA and ribonucleic acid (RNA) are nucleic acids. Alongside proteins,…
Wikipedia · DNAWhich Icelandic volcano's 1783 eruption poisoned Europe's skies?
Laki — famine followed across the continent.
Laki or Lakagígar is a volcanic fissure in the western part of Vatnajökull National Park, Iceland, not far from the volcanic fissure of Eldgjá and the small village of Kirkjubæjarklaustur. The fissure is properly referred to as Lakagígar, while Laki is a mountain that the fissure bisects. Lakagígar is part of a volcanic system centered…
Wikipedia · LakiThe Hranice Abyss, the deepest known flooded cave, was dissolved by acid rising from below in which country?
Czechia — carbonic acid ate it upward, not downward.
The Czech Republic, also known as Czechia and historically known as Bohemia, is a landlocked country in Central Europe. The country is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the southeast. The Czech Republic has a hilly landscape that covers an area of 78,871 square kilometers…
Wikipedia · Czech RepublicWhich enzyme class joins DNA fragments during replication?
Ligases — molecular glue.
In biochemistry, a ligase is an enzyme that can catalyze the joining (ligation) of two molecules by forming a new chemical bond. This is typically via hydrolysis of a small pendant chemical group on one of the molecules, typically resulting in the formation of new C-O, C-S, or C-N bonds. For example, DNA ligase can join two complementary…
Wikipedia · LigaseWhich star's 2016 planet is the nearest possibly habitable world to Earth?
Proxima Centauri — Proxima b sits 4.24 light years away.
Proxima Centauri is the nearest star to Earth after the Sun, located 4.25 light-years away in the southern constellation of Centaurus. Discovered in 1915 by Robert Innes, it is a small, low-mass star, too faint to be seen with the naked eye, with an apparent magnitude of 11.13. Proxima Centauri is a member of the Alpha Centauri star…
Wikipedia · Proxima CentauriPadparadscha, the pink-orange gem named for a lotus blossom, is a variety of which mineral?
Corundum — the same mineral as ruby and sapphire.
Sapphire is a precious gemstone, a variety of the mineral corundum, consisting of aluminium oxide (α-Al2O3) with trace amounts of elements such as iron, titanium, cobalt, lead, chromium, vanadium, magnesium, boron, and silicon. The name sapphire is derived from the Latin word sapphirus, itself from the Greek word sappheiros (σάπφειρος,…
Wikipedia · SapphireWhich superheavy element is named after the Russian town of Dubna?
Dubnium — element 105.
Dubnium is a synthetic chemical element; it has symbol Db and atomic number 105. It is highly radioactive: the most stable known isotope, dubnium-268, has a half-life of about 16 hours. This greatly limits extended research on the element.
Wikipedia · DubniumWhich quantum number describes electron spin values?
Plus or minus one half — Spin one-half, up or down.
In chemistry and quantum mechanics, the spin quantum number is a quantum number that describes the intrinsic angular momentum of an electron or other particle. It has the same value for all particles of the same type, such as s = 1/2 for all electrons. It is an integer for all bosons, such as photons, and a half-odd-integer for all…
Wikipedia · Spin quantum numberWhich sea slug photosynthesizes with stolen chloroplasts?
Elysia chlorotica — the solar-powered slug.
Sea slug is a common name for some marine invertebrates with varying levels of resemblance to terrestrial slugs. Most creatures known as sea slugs are gastropods, i.e. they are sea snails that, over evolutionary time, have either entirely lost their shells or have seemingly lost their shells due to having a significantly reduced or…
Wikipedia · Sea slugWhich deep-sea vent ecosystems run on which energy process?
Chemosynthesis — sulfur instead of sunlight.
In biochemistry, chemosynthesis is the biological conversion of one or more carbon-containing molecules and nutrients into organic matter using the oxidation of inorganic compounds or ferrous ions as a source of energy, rather than sunlight, as in photosynthesis. Chemoautotrophs, organisms that obtain carbon from carbon dioxide through…
Wikipedia · ChemosynthesisWhich comet's 1066 appearance was stitched into the Bayeux Tapestry?
Halley's Comet — Halley's — an omen over Hastings.
Halley's Comet is the only known short-period comet that is consistently visible to the naked eye from Earth, appearing roughly every 75–76 years, though with the majority of recorded apparitions occurring after 75–77 years. It last appeared in the inner parts of the Solar System in 1986 and will next appear in mid-2061. Officially…
Wikipedia · Halley's CometWhich physicist's 'demon' thought experiment challenges entropy?
Maxwell — 's demon, sorting molecules.
James Clerk Maxwell was a Scottish physicist and mathematician who was responsible for the classical theory of electromagnetic radiation, which was the first theory to describe electricity, magnetism and light as different manifestations of the same phenomenon. Maxwell's equations for electromagnetism achieved the second great…
Wikipedia · James Clerk MaxwellWhich chemist synthesized urea, ending 'vitalism' in 1828?
Friedrich Wohler — Wohler — organic from inorganic.
Friedrich Wöhler FRS(For) HonFRSE was a German chemist known for his work in both organic and inorganic chemistry, being the first to isolate the chemical elements beryllium and yttrium in pure metallic form. He was the first to prepare several inorganic compounds, including silane and silicon nitride.
Wikipedia · Friedrich WöhlerWhich theory explains why mitochondria carry their own circular DNA?
Endosymbiosis — they were free-living bacteria.
A mitochondrion is an organelle found in the cells of most eukaryotes, such as animals, plants and fungi. Mitochondria have a double membrane structure and use aerobic respiration to generate adenosine triphosphate (ATP), which is used throughout the cell as a source of chemical energy. They were discovered by Albert von Kölliker in 1857…
Wikipedia · MitochondriaWhat is the chemical symbol for tungsten?
W — from its German name Wolfram.
Tungsten is a chemical element; it has symbol W and atomic number 74. It is a metal found naturally on Earth almost exclusively in compounds with other elements. It was identified as a distinct element in 1781 and first isolated as a metal in 1783. Its important ores include scheelite and wolframite, the latter lending the element its alternative name.
Wikipedia · TungstenWhat is the name of the smallest bone in the human body?
The stapes — in the middle ear — shaped like a stirrup.
The stapes or stirrup is a bone in the middle ear of humans and other tetrapods which is involved in the conduction of sound vibrations to the inner ear. This bone is connected to the oval window by its annular ligament, which allows the footplate to transmit sound energy through the oval window into the inner ear. The stapes is the…
Wikipedia · StapesWhich element was named for a village in Sweden that also gave its name to three others?
Yttrium — Ytterby also gave terbium, erbium and ytterbium.
Which particle was detected in 1956 despite passing through a light year of lead unimpeded?
The neutrino — Reines and Cowan, beside a reactor.
Which mineral's blue was ground from a single Afghan valley for six thousand years?
Lapis lazuli — from Sar-i Sang, and nowhere else that mattered.
Which organ did the Aztecs and the Greeks both wrongly identify as the seat of thought?
The heart — Aristotle put the brain down as a radiator.
Which body's discovery in 1930 came from a systematic search for a planet that was not there?
Pluto — the predicted Planet X did not exist.
Which experiment failed to detect the medium light was assumed to travel through?
Michelson-Morley — the luminiferous ether was not there.
Which type of star serves as a standard candle because its peak brightness is always the same?
Type Ia supernova — how the accelerating universe was found.
Which organ transplant was performed first, in 1954, between identical twins?
The kidney — no rejection, because no genetic difference.
Which architectural element let Gothic cathedrals push walls aside for glass?
The flying buttress — the load is carried outside the wall.
Which metal was more valuable than gold until an 1886 electrolytic process made it cheap?
Aluminium — the Washington Monument is capped with it.