Memorize these and you could recognize 10.1% of all Science & Nature clues.
| # | Answer | Appearances | Sample Clue |
|---|---|---|---|
| 1 | water | 4 | A shark can go a lifetime without doing this; the longest a starving human has lasted is 18 days |
| 2 | gills | 4 | Most fish expel carbon dioxide through these |
| 3 | wasps | 3 | Bees live in a apiary & these live in a vespiary |
| 4 | tulip | 3 | Grown on less than 1% of the land of the Netherlands, it's their living symbol |
| 5 | Spiral | 3 | Hubble classified galaxies as being irregular, elliptical or this shape |
| 6 | quarks | 3 | These theorized subatomic particles take their name from James Joyce's "Finnegans Wake" |
| 7 | pheromones | 3 | These chemicals secreted by some animals may signal alarm or attract a member of the opposite sex |
| 8 | eyes | 3 | Snails have these organs at the end of their 2 stalks |
| 9 | cones | 3 | On spruces they hang straight down; on fir trees they stand straight up |
| 10 | algae | 3 | In wetlands, these simple plants form the base of all food chains |
| 11 | a crocodile | 3 | The mugger, known for its broad snout, is an Asian type of this large reptile |
| 12 | sheep | 3 | Typically used for mating combat, the horns of the desert species of this animal can weigh 30 pounds |
| 13 | pine | 3 | The Douglas fir is not a true fir; it belongs to this evergreen family |
| 14 | mosquito | 3 | Mosquitoes of this genus are the only ones that carry malaria |
| 15 | Wings | 2 | Unlike insects, arachnids don't have these; they can only get around on foot |
| 16 | white | 2 | The color of pure marble |
| 17 | Walrus | 2 | This tusked pinniped takes clams into its mouth & sucks the flesh from the shell |
| 18 | Venus | 2 | In March 1966 the USSR's Venera 3 became the first space probe to physically touch another planet, this one |
| 19 | tundra | 2 | The red on the flag of the Northwest Territories stands for this cold, treeless ecosystem |
| 20 | Transpiration | 2 | Most of the water that a plant absorbs from the soil is released as vapor during this process |
| 21 | the speed of light | 2 | Einstein's famous equation states energy equals mass times this squared |
| 22 | the monarch | 2 | Flying great distances at speeds near 20 mph, this butterfly is often called "The Wanderer" |
| 23 | the husk | 2 | They're the leaves that enclose & protect an ear of corn |
| 24 | teeth | 2 | Fossil records show these body parts are 1/2 the size they once were, perhaps due to cooked foods |
| 25 | squirrel | 2 | The wolf & this rodent both have "red" & "gray" types, but there's no flying wolf |
| 26 | Snake | 2 | A puffer is a fish & a puff adder is a poisonous type of this |
| 27 | skipjack | 2 | This variety of tuna is named for its habit of "skipping" over the water |
| 28 | sand | 2 | The glass used in most windows is made from a mixture of lime, soda & this |
| 29 | Salamander | 2 | It's any tailed amphibian, including the newt |
| 30 | rings | 2 | Like a tree, you can tell the age of a fish by counting these on its scales |
| 31 | quartz | 2 | Rock crystal is a colorless variety of this mineral, & amethyst is the purple variety |
| 32 | pink | 2 | Distinguishing eye color of a true biological albino |
| 33 | negative | 2 | In 1955 physicists Owen Chamberlain & Emilio Segre discovered the antiproton, which has this kind of charge |
| 34 | Molting | 2 | It's the process by which a snake sheds its skin or a deer its antlers |
| 35 | magma | 2 | When it flows out of the earth, it becomes lava; when blasted into tiny fragments, it becomes volcanic ash |
| 36 | Lucy | 2 | Discovered in 1974, the oldest skeleton of a female hominid is nicknamed this, after a Beatles song |
| 37 | lizards | 2 | Some of the fanciest of these reptiles are beaded, horned, or frilled |
| 38 | lightning | 2 | This strikes the Earth about 100 times each second & often in the same place twice |
| 39 | John Muir | 2 | Blinded in 1867, he vowed to "see God's wilderness", recovered his sight, & ended up in Yosemite |
| 40 | hibernation | 2 | Chipmunks go into a sleeplike state called torpor during this winter period |
| 41 | henna | 2 | The scented flowers of this shrub are used in perfume & its reddish dye is used as a hair coloring |
| 42 | Hawaii | 2 | 75 miles long & 64 miles wide, the Mauna Loa volcano in this state is the world's largest active volcano |
| 43 | glaciers | 2 | A branch of geology studies these ice masses, which formed the Svealand area where we're taping "Jeopardy!" |
| 44 | fungi | 2 | Mildews, smuts & morels belong to this group of organisms incapable of making their own food |
| 45 | Florida | 2 | In the U.S., alligators & crocodiles co-exist only at the southern tip of this state |
| 46 | feathers | 2 | This bodily feature makes birds different from all other animals |
| 47 | edelweiss | 2 | German for "noble" & "white", this noble white flower is identified with both Austria & Switzerland |
| 48 | dwarfs | 2 | Our sun is classified as the yellow type of these "small" stars |
| 49 | deciduous | 2 | Unlike most of its pine family relatives, the larch is classified as this, as it loses its needles each fall |
| 50 | Darwin | 2 | In 1872 this British naturalist wrote "The Expression of the Emotions in Man and Animals" |