1. Photosynthesis

2. Why Study Plants? plants The basic food for all organisms is produced by plants food oxygen The only source of food and oxygen comes from plants Plants provide us with shelter, clothing, furniture, paper products, and certain medicines like aspirin Plants are ultimately responsible for the gas in your car along with other fossil fuels!

3. A Little Review… autotrophs Plants are autotrophs - meaning they make their own food heterotrophs Organisms that cannot make their own food and must rely on other organisms for nutrition are called heterotrophs AUTO=SELF HETERO = OTHER

4. Energy Transformations Energy Energy is the ability to do work There are many forms of energy including: Heat, Light, Sound, Electrical, and Chemical Energy transformed Energy can be transformed from one form to another

6. sun The sun is the ultimate source of energy for life on Earth PHOTOSYNTHESIS Plants convert the energy from sunlight to the energy of glucose = PHOTOSYNTHESIS Chemical Energy (Glucose) – Light Energy Chemical Energy (Glucose) Glucose

7. sunlightwater and carbon dioxide sugars (glucose). Photosynthesis = the process by which sunlight (solar energy) converts water and carbon dioxide into chemical energy stored in simple sugars (glucose). This process can be represented using a chemical equation

8. The Equation

9. Reactants Products Light H2OH2OCO 2 O2O2 C 6 H 12 O 6 Glucose Chloroplast Light Dependent Reaction Calvin Cycle NADP+ ADP + P ATP NADPH

10. chloroplastsPhotosynthesis occurs in the chloroplasts of plants

11. Leaf Anatomy Stoma gases Stoma (Stomata) - Pores in a plant’s cuticle through which gases are exchanged between the plant and the atmosphere Carbon Dioxide (CO 2 ) Oxygen (O 2 )

12. So Why are Leaves Green? chlorophyll. The green color is caused by a chemical called chlorophyll. absorbing Chlorophyll pigments harvest energy by absorbing certain wavelengths of light reflected Plants are green because the green wavelength is reflected, not absorbed Absorbed light Chloroplast Reflected light Light

13. The Process of Photosynthesis occurs in 2 stages… 1.Light-Dependent Reactions 2.Dark (Light- Independent) Reactions

14. Light-Dependent Reactions Requires Requires Light ATP and NADPH Solar energy is absorbed by chlorophyll and temporarily stored in energy carriers, ATP and NADPH Water oxygen Water is split by the absorbed energy which results in the release of oxygen as a waste product Light Reactions NADPH O2O2 H2OH2O ATP

15. Dark (Light-Independent) Reactions Calvin Cycle Also called the Calvin Cycle Not Do Not require solar energy transferred glucose Energy is transferred from ATP and NADPH to the organic compound glucose NADPHATP Dark Reactions (Calvin Cycle) Energy from Sugar (Glucose)

16. What happens to the glucose? cellular respiration It can be used by the plant as a form of energy through the process of cellular respiration starch, cellulose, or other organic compounds Can be converted to starch, cellulose, or other organic compounds Glucose

17. In Summary…