Question

Which number remains unchanged during photosynthesis?
A. the number of water molecules
B. the number of glucose molecules
C. the number of carbon atoms
D. the number of carbon dioxide molecules

Answer 1

During photosynthesis, the number of carbon atoms remains unchanged. This is because carbon dioxide (CO2) is converted into glucose (C6H12O6), but the total number of carbon atoms involved in the reaction stays constant. Water (H2O) is also consumed and converted, and the number of glucose molecules produced can vary depending on the conditions, but the carbon atoms from carbon dioxide that are integrated into glucose are balanced by those in the carbon dioxide molecules consumed.

Therefore, the correct answer is:
C. the number of carbon atoms