Every culture that has adopted the cultivation of maize—also known as corn—has been radically changed by it. This crop reshaped the cultures of the Native Americans who first cultivated it, leading to such developments as the adoption of agrarian and in some cases urban lifestyles, and much of the explosion of European much more bountiful than others? Modern biochemistry has revealed the physical mechanism underlying maize’s impressive productivity.
To obtain the hydrogen they use in the production of carbohydrates through photosynthesis, all plants split water into its constituent elements, hydrogen and oxygen. They use the resultant hydrogen to form one of the molecules they need for energy, but the oxygen is released into the atmosphere. During photosynthesis, carbon dioxide that atmospheric conditions, oxygen begins to bind competitively to the enzyme, thus interfering with the photosynthetic reaction.
Some plants, however, have evolved a photosynthetic mechanism that prevents oxygen from impairing photosynthesis. These plants separate the places where they split water atoms into hydrogen and oxygen from the places where they build sugars from carbon dioxide. Water molecules are split, as in all plants, in specialized chlorophyll-containing structures in the Such C-4 plants as sugar cane, rice, and maize are among the world’s most productive crops.
What this question is testing
Your task
Pin down exactly what the question asks about the passage — a detail, the author's view, the structure, or the main point — before looking at the choices.
Common trap
Answers that restate a true detail from the passage but don't answer the specific question being asked.
Winning move
Anticipate the answer in your own words from the passage, then find the choice that matches that prediction.
Reading along? Open the full official question in LawHub — we show a fragment here and keep the reasoning in our own words.