1. Photosynthesis

2. How do we know that plants make carbohydrates from just carbon dioxide water and light energy?  For example: Jan Baptisa van Helmont (1648) planted a willow branch weighing 5 pounds into 200 pounds of soil and then after 4 years the tree weighed 169 lbs. and the soil was still nearly 200 lbs. Experiments!

3. Plant leaves have many types of cells!

4. Chloroplasts make the sugars!

5. The Calvin cycle makes sugar from carbon dioxide –ATP generated by the light reactions provides the energy for sugar synthesis –The NADPH produced by the light reactions provides the electrons for the reduction of carbon dioxide to glucose Light Chloroplast Light reactions Calvin cycle NADP  ADP + P  The light reactions (light dependent)convert solar energy to chemical energy  Produce ATP & NADPH and O2(split H2O) PHOTOSYNTHESIS

6. Plants produce O 2 gas by splitting H 2 O  The O 2 liberated by photosynthesis is made from the oxygen in water (H + and e - )

7. Steps of Photosynthesis  Light hits reaction centers of chlorophyll, found in chloroplasts Chlorophyll vibrates and causes water to break apart. Oxygen is released into air Hydrogen remains in chloroplast attached to NADPH “THE LIGHT REACTION”

9.  The DARK Reactions= Calvin Cycle CO2 from atmosphere is joined to H from water molecules (NADPH) to form glucose Glucose can be converted into other molecules with yummy flavors!