# What provides the carbon atoms that are incorporated into sugar molecules in the Calvin cycle?

May 24, 2016

The carbon atoms come from carbon dioxide.

#### Explanation:

The Calvin cycle is a series of biochemical redox reactions that take place in in photosynthetic organisms.

The cell first captures the energy of light and uses it to make $\text{ATP}$ and $\text{NADPH}$.

The Calvin cycle then uses this energy to convert carbon dioxide and water into glyceraldehyde-3-phosphate ($\text{G3P}$) for use in other metabolic reactions.

$\text{3CO"_2 + "6NADPH" + "9ATP" + "6H"^+ → underbrace("C"_3"H"_6"O"_3"-P")_color(red)("G3P") + "6NADP"^+ + "9ADP" + "8P"_i +"3H"_2"O}$