Section: Natural Sciences

21) In the "dark reactions" of photosynthesis,

1. carbon dioxide is absorbed.
2. radiant energy is released.
3. radiant energy is changed to chemical energy.
4. chemical energy is changed to radiant energy.
5. organic synthesis occurs.

The dark reactions of photosynthesis include the reduction of carbon dioxide and its combination into 3- and -6-carbon sugars. This is followed by a series of reactions in which the sugar ribulose is replaced.