OVERVIEW OF PHOTOSYNTHESIS HW 3-4 AUTOTROPHS SUCH AS PLANTS, ALGA, PROTISTS, CYANOBACTERIA AND PURPLE SULFUR BACTERIA CONVERT LIGHT ENERGY FROM THE SUN INTO STORED CHEMICAL ENERGY Link Photosynthesis overview

Overall photosythesis rxn: 6 CO2 + 6 H2O → C6H12O6 + 6 O2 Objective of photosynthesis: Synthesize carbohydrates from CO2 and H2O Light energy is added to drive rxn

Comparison of Photosynthesis and Aerobic Respiration Aerobic heterotrophs have only mitochondria whereas photoautotrophs have both mitochondria and chloroplasts 6 CO2 + 6 H2O + Light energy  C6H12O6 + 6 O2 C6H12O6 + 6 O2  6 CO2 + 6 H2O + Energy for life’s work (ATP + heat) Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

Link to mitochondria and chloroplasts

Figure 10.2 Focusing in on the location of photosynthesis in a plant STOMATA = plural of STOMA Link to VA Tech Photosynthesis Animation STOMA : AN OPENING IN THE LEAF FOR EXCHANGING GASES Mesophyll cells contain chloroplasts STROMA – Fluid in chloroplast surrounding Thylakoid membrane; site of Calvin Cycle TEM = Transmission Electron Microscopy

CROSS SECTION OF A CHLOROPLAST STROMA – Fluid in chloroplast surrounding Thylakoid membrane; site of Calvin Cycle THYLAKOID – disc shaped membrane enclosed compartment; site of Light Reactions LAMELLA – connects Granum GRANUM – stack of thylakoids

Figure 10.4 An overview of photosynthesis: cooperation of the light reactions and the Calvin cycle (Layer 1)

Figure 10.4 An overview of photosynthesis: cooperation of the light reactions and the Calvin cycle (Layer 2)

Figure 10.4 An overview of photosynthesis: cooperation of the light reactions and the Calvin cycle (Layer 3)

Figure 10.4 An overview of photosynthesis: cooperation of the light reactions and the Calvin cycle (Layer 3)