Corn does grow from a grass, quite a small one called teosinte. It is a small grass that produces hard-to-get-at, TINY grains and was genetically cultured into the grain we know today.

Most of the peoples in MesoAmerica and North American treated their corn grains, however. Even today, a real tortilla is made by first soaking the corn in a lime (the stone, not the fruit) solution to break down the anti-nutrients and free up the good stuff to make it more edible. The corn is then drained, ground into a dough and made into the thin flatbreads that are then cooked over a hot fire on a stone surface.

Also, as to the three sisters, the squash was very important because it provided the greens! The leaves and flowers were eaten just as much, if not more so than the fruit itself. The fruits were of course often used to make dishes and other container-type tools. Beans were often treated the same was as corn, soaking and fermenting them. Sprouting certainly occurred as well. Corn was also used as the basis of some fermented drinks, though most in the South came from the agave instead (pulque is my favorite).

It's a member of the botanical family Poaceae cultivated for the edibility of its seeds. That makes it a cereal grain.

While corn is technically a grain, i eat it on or immediately off the cob. I usually have it about once a week in season.

Corn products on the other hand, I won't touch them.

According to this book, Native Americans engineered corn and were very, very much involved in agriculture, to the point that their civilizations were somewhat destroyed before they were "discovered" by the European explorers.

I lack the education to give a scientific answer, but for me corn is very different from wheat. Whether it's sweet corn or nachos, I seem to lack the ability to break down and digest corn--it emerges mostly unchanged. Despite the clear problems I have after wrestling with wheat, I do seem to digest it although with definite consequences.

Since most corn is genetically modified in the US I wont touch the stuff regardless of if it is a grain or a vegetable. Oh and by the way congress decided that Pizza is now a vegetable so we can all go back to eating pizza again.

Pizza is a vegetable

To add insult to injury our tax dollars are paying for our kids to eat this crap.

American natives are Asiatic neolithics. Farming - whether corn in Mexico or potatoes in the Andes - is a "transplanted" activity.