1. Keystone Review Photosynthesis 1.A – Photosynthesis produce glucose, oxygen is not needed, but it is produced as a waste product. 2.B – Choices A, C, D; (sunlight is absorbed, a water molecule is split and oxygen is released) all occur in the thylakoid. 3.D – Plants use carbon dioxide in photosynthesis, if there is less plants they would use less carbon dioxide and more would be left in the atmosphere. 4.B – In photosynthesis carbon dioxide and water are the reactants; oxygen and glucose are the products.

2. Keystone Review Photosynthesis Open Ended Question A. The original source of energy is the sun. Sunlight is absorb by chlorophyll in the plant. The light energy is converted into chemical energy, such as glucose. The glucose is consumed by an animal who then used cellular respiration to convert glucose into ATP.

3. Keystone Review Photosynthesis Open Ended Question B. In the plant light energy from the sun is converted in chemical energy in a glucose molecule. In the animal chemical energy in glucose is converted into chemical energy in ATP. Throughout this process some energy is lost as heat.

4. Keystone Review Photosynthesis Open Ended Question C. When ATP is converted into ADP and a phosphate group, most of the energy contained in the molecule of ATP is used in another chemical reaction that takes place in a cell. Some energy is lost as heat.