Gibbons, small Asian apes, move by brachiation, swinging below a handhold to move forward to the next handhold. A 8.6 kg gibbon has an arm length (hand to shoulder) of 0.60 mm. We can model its motion as that of a point mass swinging at the end of a 0.60-mm-long, massless rod. At the lowest point of its swing, the gibbon is moving at 3.5 m/s. Required:
What upward force must a branch provide to support the swinging gibbon?

The answer is water molecules are split.cellular respiration and photosynthesis are complement  reactions to each other. these are reverse reactions. in cellular respiration glucose and oxygen yield water and carbon dioxide. so, when respiration begins,  glucose molecules are split. in the opposite reaction - in photosynthesis, carbon dioxide and water yield glucose and oxygen. thus,  when respiration begins, water molecules are split.

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