The only known "solution" to the loss of efficiency caused by the oxygenation of RuBP by rubisco is to raise the concentration of CO₂ in the cell using energy from ATP. Which of the following is MOST correct of such plants? A)They are tolerant of shade. B)They are often found in bright, sunny habitats. C)They do not produce O₂. D)They do not produce reactive O₂ species. E)They require high CO₂ levels.

Question

Quizplus · Accepted Answer

Plants that have evolved the mechanism of raising the concentration of CO₂ in the cell to counteract the loss of efficiency caused by oxygenation of RuBP by rubisco are known as C4 plants. These plants are often found in bright, sunny habitats because they require a lot of light to fuel their energy-demanding mechanism for producing and concentrating CO₂. Shade-tolerant plants, on the other hand, have adaptations that allow them to photosynthesize under low light conditions. Option A is incorrect. Option C is incorrect because C4 plants do produce CO₂. Option D is incorrect because the concentration of reactive oxygen species is not related to the C4 mechanism. Option E is partially correct, but not the most accurate answer. C4 plants require high CO₂ levels, but this is not the defining factor for their occurrence in bright, sunny habitats.

The Only Known "Solution" to the Loss of Efficiency Caused