Refer to the graph below showing data collected from experiments performed on living leaves attached to two different plants, maize and bean.The rate of photosynthesis in each leaf was measured at varying concentrations of carbon dioxide present in the intercellular spaces within the leaves. Based on these results, what is the likely classification of maize and bean plants, and which plant would grow better at reduced carbon dioxide levels? A) Maize and bean are both C₄ plants, and maize would grow better than bean plants at low carbon dioxide levels. B) Maize and bean are both C₃ plants, and maize would grow better than bean plants at low carbon dioxide levels. C) Maize is a C₄ plant, bean plants are C₃, and bean plants would grow better than maize at low carbon dioxide levels. D) Maize is a C₄ plant, bean plants are C₃, and maize would grow better than bean plants at low carbon dioxide levels. E) Bean plants are C₄ plants, maize is C₃, and bean plants would grow better than maize at low carbon dioxide levels.

Question

Quizplus · Accepted Answer

The graph shows that both maize and bean plants have decreasing rates of photosynthesis as carbon dioxide levels decrease, indicating that they are both C3 plants. However, maize has a higher rate of photosynthesis than bean at all carbon dioxide levels, suggesting that it is a more efficient C3 plant. Therefore, maize is a C₄ plant while bean plants are C₃. Additionally, the graph shows that maize has a higher rate of photosynthesis than bean at all carbon dioxide levels, suggesting that maize would grow better than bean plants at low carbon dioxide levels. Therefore, the correct answer is D: Maize is a C₄ plant, bean plants are C₃, and maize would grow better than bean plants at low carbon dioxide levels.

Refer to the Graph Below Showing Data Collected from Experiments