Biology: Concepts and Investigations 2nd Edition by Mariëlle Hoefnagels

Exercise 27

Suppose that a scientist exposes a leaf to CO2 labeled with carbon-14, and the radioactive carbon is incorporated into organic compounds in photosynthetic cells. At various times after exposure, the scientist can determine the location of the radioactive carbon in the plant. In what tissues do you expect to find the radioactive material immediately after exposure to the labeled carbon? What about during transport? When transport is complete, will the radioactive material be in plant parts above the leaf, below the leaf, or both?