Campbell Biology (11th Edition)

Published by Pearson
ISBN 10: 0-13409-341-0
ISBN 13: 978-0-13409-341-3

Chapter 10 - 10.1 - Concept Check - Page 192: 2


By using heavy oxygen (oxygen-18), researchers showed that the label only ended up in carbohydrates if the label was put in the water which plants received-- not when it was added to carbon dioxide. This shows that the oxygens in the products of photosynthesis come from water.

Work Step by Step

This is an example of how unusual isotopes of natural elements (radioactive or heavy isotopes, usually) because they are different from most of the natural form of the element, can be used to trace the process of biochemical reactions. It is important to see, here, that this work proves the important role of water as a reactant in photosynthesis.
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.