Question

An important difference between cellular respiration and photosynthesis is that when cellular respiration begins, glucose molecules are split. However, when photosynthesis begins
ADP molecules are split.
water molecules are split.
oxygen molecules are split.
carbon dioxide molecules are split.

Answer 1

water molecules are split.

In the light-dependent reactions of photosynthesis, water is split (photolysis) to provide electrons and protons and to release O2. In contrast, cellular respiration begins with glucose being broken down (glycolysis).