<em>Answer: Photosynthesis is when energy, carbon dioxide and water react to produce glucose and oxygen. It is an endothermic reaction takes in more energy than it gives off. Respiration is the process of producing energy from glucose.</em>
The principal difference, however, between photosynthesis and respiration is that photosynthesis utilizes carbon dioxide and water in the presence of light to produce glucose and oxygen, whereas respiration uses oxygen and glucose to power the activities of the cell.
The preposition of the sentence would be the word "of" since it relates the subject, the Incas, to the clause, which is "possessions with special knotted cords called quipu."
