Question

Which of the following statements best explains the ability of cam plants to synthesize sugars in the daytime while keeping their stomata closed to reduce water loss?

1) CAM plants have a unique photosynthetic pathway that allows them to fix carbon dioxide at night and store it as malic acid in their vacuoles. During the day, the malic acid is converted back to carbon dioxide, which is then used in the Calvin cycle to synthesize sugars.
2) CAM plants have a higher concentration of chlorophyll in their leaves, which allows them to carry out photosynthesis more efficiently in low light conditions.
3) CAM plants have specialized cells called bundle sheath cells that surround their vascular tissue, allowing them to efficiently transport sugars from the leaves to other parts of the plant.
4) CAM plants have a unique enzyme called PEP carboxylase, which allows them to fix carbon dioxide more efficiently than other plants.

Answer 1

CAM plants use a specialized photosynthetic pathway to synthesize sugars during the day without opening their stomata, by fixing CO2 at night and storing it as malic acid which is later used in the Calvin cycle.

Step-by-step explanation:

The ability of CAM plants to synthesize sugars in the daytime while keeping their stomata closed to reduce water loss is best explained by the unique photosynthetic pathway that these plants possess. CAM plants fix carbon dioxide at night when the stomata are open and store it as malic acid in their vacuoles. During the day, the stomata are closed to conserve water, and the malic acid is then converted back to carbon dioxide for use in the Calvin cycle to synthesize sugars.

Thus, the correct statement is: CAM plants have a unique photosynthetic pathway that allows them to fix carbon dioxide at night and store it as malic acid in their vacuoles. During the day, the malic acid is converted back to carbon dioxide, which is then used in the Calvin cycle to synthesize sugars.