Question

what happpends to a carbon atom during the proces of photosynthesis

Answer 1

Plants use the process of photosynthesis to change carbon dioxide into oxygen, as well as to create food for themselves. This makes plants a good complement to the human race as humans breathe out carbon dioxide, which the plants then turn it into the oxygen humans need to live. Plants and humans need each other to survive.

Answer 2

I think that's^ from here: http://www.ehow.com/info_8527975_happens-carbon-dioxide-during-photosynthesis.html

Great answer @ZhangYan , just please remember to cite! :)

A similar question was posed before, and a number of nice answers have accrued there. Perhaps you can take a look there first?
http://openstudy.com/study#/updates/4f875483e4b0505bf086e271