If true, which of the following is the best evidence that the cyanelles are providing nutrition (in other words, calories) to the surrounding cercozoan?
A) if the cyanelle performs aerobic photosynthesis
B) if the vesicle membrane that surrounds each cyanelle possesses glucose-transport proteins
C) if the cyanelle performs aerobic respiration
D) if radiolabeled 14CO2 enters the cyanelle and if, subsequently, radiolabeled glucose is present in cercozoan cytosol
E) if radiolabeled "heavy" water, 2H2O, enters the cyanelle and if, subsequently, radiolabeled oxygen appears in cercozoan cytosol

Question

Quizplus · Accepted Answer

Radiolabeled 14CO2 entering the cyanelle and the subsequent appearance of radiolabeled glucose in the cercozoan cytosol would indicate that the cyanelles are providing calories to the cercozoan through photosynthesis. This is because the radiolabeled 14C from the CO2 would be incorporated into the glucose during photosynthesis, and then transferred to the cercozoan for energy use. Options A and C are not relevant as they describe the type of metabolism performed by the cyanelle, rather than the transfer of nutrients to the cercozoan. Option B could be a potential mechanism for nutrient transfer, but its presence alone does not necessarily indicate that the cyanelle is providing nutrients to the cercozoan. Option E describes the movement of oxygen, which is not directly indicative of nutrient transfer.

If True, Which of the Following Is the Best Evidence