Getting your questions ready
Getting your questions ready
Beat the crowd
10 questions No timer
This corn trivia quiz has 50 free questions with answers and covers the whole plant and everything made from it: where maize was domesticated and from what, how a cob is built, why the world grows more of it than wheat or rice, and how the Maya's alkali trick kept them healthy while Europeans who copied the crop got sick. Then it moves to the fun stuff: how popcorn pops and what the unpopped kernels are called, why bourbon has to be at least half corn, who invented candy corn and corn flakes, the record corn maze, the Corn Palace and its mascot. The opening questions suit a classroom or a harvest-festival table; the back half will test a farmer or a food historian. Every answer comes with a short explanation. Every question has been checked against a primary source, mostly Wikipedia's maize, popcorn and food-history articles, and shows its citation once you have answered.
30 of 50 questions with answers and explanations. Play the quiz
Q 01Outside North America, corn is usually known by what name?
Maize
Maize, the name used across most of the world, comes via the Spanish maíz from the Taíno mahiz; Linnaeus used it for the species name Zea mays in 1753.
Q 02Corn was first domesticated about 9,000 years ago in which present-day country?
Mexico
Maize was domesticated about 9,000 years ago in the Balsas River valley of southern Mexico, where its wild ancestor, a short bushy grass that looks nothing like a cornstalk, grows.
Q 03What is the wild grass from which corn was domesticated?
Teosinte
Teosinte, a bushy wild grass of Mexico, is maize's ancestor; changes in a handful of genes, notably tb1 and tga1, account for most of the difference between its many thin branches and maize's single tall stalk.
Q 04Native Americans grew corn alongside beans and squash in a planting system known as what?
The Three Sisters
In the Three Sisters system cornstalks held up the climbing beans, the beans fixed nitrogen for the soil, and broad squash leaves shaded out weeds and kept the ground moist.
Q 05The male flowers at the top of a cornstalk are called what?
The tassel
The tassel is the cluster of male flowers at the top of the stalk; its pollen drifts on the wind down to the silks, the female parts that emerge from the developing ear.
Q 06Each strand of corn silk connects to what?
A single kernel
Each silk strand is the style of one female flower; a pollen grain landing on it grows a tube down to fertilise a single kernel, so every kernel on the cob has its own silk.
Q 07Roughly how many kernels can a large cob of corn hold?
Up to 1,200
A large cob can hold up to 1,200 kernels, though a typical ear carries about 800 in 16 rows; the row count is always even because the kernels form in paired spikelets.
Q 08Which pigments give yellow corn its colour?
Carotenoids
Carotenoids such as zeaxanthin, lutein and beta-carotene colour yellow corn; red and blue varieties get their colour from anthocyanins and phlobaphenes instead.
Q 09In which decade did the world corn harvest first pass one billion tonnes?
2010s
World corn output first topped one billion tonnes in 2013, in the 2010s, and reached about 1.16 billion in 2020, more than wheat and rice (about 760 million tonnes each), with most going to feed and industry.
Q 10Which country grew the most corn in 2020, with about 31 percent of world output?
The USA
The USA grew about 360 million tonnes of corn in 2020, roughly 31 percent of the world total; China was second with about 22 percent and Brazil a distant third.
Q 11Which type of corn makes up almost all the grain corn grown commercially in the US?
Dent corn
Dent corn, named for the dimple that forms in each kernel as its soft starchy core dries, accounts for nearly all US commercial grain corn; sweet corn is a mutant that fails to turn sugar into starch.
Q 12At which kernel stage is sweet corn picked, before its sugars turn to starch?
The milk stage
Sweet corn is picked at the milk stage, when a punctured kernel oozes milky juice; field corn is left until the kernels are dry and dented, while sweet corn must be eaten, canned or frozen fast.
Q 13Corn syrup is made by breaking down which component of the corn kernel?
Starch
Q 21Corn uses which photosynthetic pathway, shared with sugarcane and sorghum?
C4
Corn is a C4 plant, like sugarcane and sorghum: it concentrates CO2 in bundle-sheath cells, which lets it keep its stomata more closed and use water far more efficiently than C3 crops such as wheat and soybeans.
Q 22US corn yields climbed sharply from the 1930s after farmers adopted what kind of seed?
Hybrid seed
Hybrid seed, produced by crossing inbred lines, swept the Corn Belt in the 1930s and 1940s; Iowa went from a few percent hybrid in the early 1930s to nearly all hybrid by 1940, and yields climbed steadily after.
Q 23Apart from animal feed, what has been the US corn crop's biggest use since 2010?
Ethanol fuel
Corn syrup is made by hydrolysing cornstarch into glucose with acids or enzymes; high-fructose corn syrup goes a step further, converting part of that glucose into fructose.
Q 14Old American farm wisdom said a good crop was on track if the corn was 'knee-high' by when?
The Fourth of July
The saying was 'knee-high by the Fourth of July'; modern hybrids, planted earlier and growing faster, are often shoulder-high or taller by Independence Day.
Q 15Soaking corn in alkali water, a process the Maya used, is called what?
Nixtamalization
Nixtamalization, from the Nahuatl words for ashes and dough, means soaking and cooking corn in limewater or wood-ash lye; it loosens the hull, improves flavour and unlocks bound nutrients.
Q 16Which deficiency disease broke out wherever unprocessed corn became a staple food?
Pellagra
Pellagra, the niacin-deficiency disease marked by dermatitis, diarrhoea and dementia, swept corn-dependent populations in Europe and the US South; alkali treatment, used by Mesoamericans for millennia, unlocks the grain's bound niacin.
Q 17The dough made from nixtamalized corn, the base of tortillas and tamales, is called what?
Masa
Atole is the drink made from it; polenta and grits are the Italian and Southern US porridges made from plain cornmeal.
Q 18Mămăligă, a thick cornmeal porridge, is a national dish of which country?
Romania
Mămăligă is Romania's traditional cornmeal porridge, also a staple in neighbouring Moldova; its cousins include Italian polenta, Brazilian angu, South African mieliepap and East African ugali.
Q 19Who first brought corn to Africa, where it is now the most important staple crop?
The Portuguese
It arrived in the 16th century and spread because it grows in so many climates.
Q 20For which food did early Spanish settlers refuse to substitute corn flour for wheat?
Communion bread
Communion bread had to be wheat: church doctrine held that only wheat bread could become the body of Christ, so settlers shipped or grew wheat at any cost.
Ethanol fuel has taken roughly a third or more of the US corn crop since the late 2000s, driven by the Renewable Fuel Standard of 2005 and 2007; exports and corn syrup take far smaller shares.
Q 24Bourbon whiskey must legally be made from a mash of at least what proportion of corn?
51%
Federal rules require a bourbon mash of at least 51 percent corn, aged in new charred oak containers; Congress declared bourbon a 'distinctive product of the United States' in 1964.
Q 25The 'HFCS 55' grade of high-fructose corn syrup is used mostly to sweeten what?
Soft drinks
HFCS 55, about 55 percent fructose, is the grade used in US soft drinks such as Coca-Cola and Pepsi; HFCS 42, with less fructose, goes into processed foods, baked goods and cereals.
Q 26Will Kellogg created corn flakes in 1894 as food for what kind of institution?
A sanitarium
The flakes were made for the Battle Creek Sanitarium, the Michigan health resort run by Will's brother John Harvey Kellogg; the brothers later fought a long legal battle over use of the Kellogg name.
Q 27Which former Battle Creek patient set up a rival breakfast cereal business to Kellogg's?
C. W. Post
C. W. Post, a Battle Creek Sanitarium patient in 1891, founded the Postum Cereal Company in 1895 and launched Grape-Nuts in 1897; Kellogg's later answered with Rice Krispies in 1928.
Q 28Popcorn kernels expand to roughly what multiple of their original size when they pop?
20 to 50 times
A popping kernel expands to 20 to 50 times its original volume; steam pressure inside the hull reaches about 135 psi before it bursts and the starch puffs into foam.
Q 29At roughly what temperature does a popcorn kernel finally burst?
180 °C (356 °F)
At about 180 °C (356 °F) the hull gives way; the starch inside has already gelatinised, so the escaping steam whips it into an airy foam that sets as it cools.
Q 30Kernels that fail to pop are known in the popcorn trade by what nickname?
Old maids
'Old maids', also called spinsters, are the kernels that never pop, usually because they lack enough moisture to build up steam or have a cracked hull that cannot hold pressure.