1. Photosynthesis

2. Autotrophs vs. Heterotrophs Autotrophs Organisms that use the sun’s energy to make their own food Plants Some bacteria Heterotrophs Organisms that must consume other organisms to obtain energy Animals Some Bacteria Fungi

3. Plants Unicellular protist Multicellular algaeCyanobacteria Purple sulfur bacteria 10 µm 1.5 µm 40 µm

4. Identifying Autotrophs and Heterotrophs Rose Human Tiger Palm Tree Fern Mushroom Sea Weed Venus Fly Trap Autotroph Heterotroph Autotroph Heterotroph Autotroph

5. Photosynthesis Equation for reaction 6CO 2 + 6H 2 O  C 6 H 12 O 6 + 6O 2 carbon dioxide + water  sugar + oxygen Requirements for the reaction Water Carbon dioxide Light Chlorophyll (found in chloroplasts)

6. Pigments Primary Pigments Chlorophyll a Chlorophyll b Secondary Pigments Carotene Red/orange Xanthophyll yellow

7. Absorption of Light by Chlorophyll a and Chlorophyll b VBGYOR Chlorophyll b Chlorophyll a Section 8-2 Go to Section:

8. Light Energy Chloroplast CO 2 + H 2 OSugars + O 2 Section 8-2 Photosynthesis: Reactants and Products Go to Section:

9. Inside a Chloroplast Thylakoids Photosynthetic membranes Arranged in stacks (called grana) Contain pigments Site of the light-dependent reactions Stroma Area around thylakoid membranes Site of the Calvin Cycle (light-independent reactions)

10. Chloroplast Light & water O2O2 Sugars CO 2 Light- Dependent Reactions Calvin Cycle NADPH ATP ADP + P NADP + Chloroplast Section 8-3 Photosynthesis: An Overview Go to Section:

11. Light-Dependent Reactions Occur in the thylakoid membranes Require light Occur during the day time Produce: Oxygen ATP and NADPH (energy carriers)

12. Calvin Cycle Occur in the stroma Also called the Light-Independent Reactions Do not require light Can occur during the day or night Uses ATP and NADPH to produce sugars

13. H2OH2O LIGHT REACTIONS Chloroplast Light

14. H2OH2O LIGHT REACTIONS Chloroplast Light ATP NADPH O2O2

15. H2OH2O LIGHT REACTIONS Chloroplast Light ATP NADPH O2O2 NADP + CO 2 ADP P + i CALVIN CYCLE [CH 2 O] (sugar)

16. Factors Affecting Photosynthesis Water shortage Temperature (best temp 0-35 Celsius) Intensity of light