Popped Secret: The Mysterious Origin of Corn

What is the process by which humans transform wild plants into useful crops?

• Genetic engineering

• Natural selection

• Domestication

• Hybridization

Which of the following products commonly contains corn or is derived from corn-fed animals?

• Cornbread

• Corn syrup

• Beef

• All of the above

What made the origin of maize a mystery compared to other crops like wheat and apples?

• Maize was discovered much later than other crops.

• The wild ancestors of wheat and apples look similar to their cultivated forms, but no wild plant today resembles maize.

• Maize requires specific soil conditions not found in the wild.

• Early humans did not document the domestication of maize.

What was the name of the grass from Central America that George Beadle identified as the likely ancestor of maize?

• Wheatgrass

• Teosinte

• Sorghum

• Barley

Which of the following is a key difference between teosinte and modern maize?

• Teosinte has a single main stalk, while maize is bushy.

• Maize kernels are enclosed in hard fruit cases, while teosinte kernels are exposed.

• Teosinte has many branches, and its kernels are enclosed in hard fruit cases.

• Maize and teosinte have identical branching patterns.

If two genes are responsible for the differences between maize and teosinte, what is the probability of an F2 plant resembling teosinte?

• 1/4

• 1/16

• 1/64

• 1/256

Based on the experiment where 1 in 500 F2 plants resembled teosinte, how many genes were suggested to be responsible for the major differences between maize and teosinte?

• 1-2 genes

• 2-3 genes

• 3-4 genes

• 4-5 genes

Where did the teosinte variety that is the ancestor of all modern corn originate?

• Central America

• Northern Mexico

• Southwestern Mexico near the Balsas River

• Eastern United States

What method did Dobley's team use to estimate how long ago the paths of teosinte and corn separated?

• Radiocarbon dating of ancient cobs

• Analyzing differences in DNA sequences and mutation rates

• Comparing physical characteristics of ancient seeds

• Observing the growth patterns of modern teosinte and corn

How did archaeologists determine the age of the ancient maize microfossils found on grinding tools?

• By directly radiocarbon dating the microfossils

• By comparing the microfossils to modern maize samples

• By radiocarbon dating charcoal found in the same sediment layer as the grinding stones

• By analyzing the wear patterns on the grinding tools