1. An Overview of Photosynthesis & Respiration
2. Autotrophs and producers
3. Electromagnetic Spectrum & light energy
4. Chloroplasts: Structure and Function
5. Photosynthetic pigments
6. Chemical Reactions of Photosynthesis
Outline - Photosynthesis
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
CO2
H2O
Glucose
O2
ATP
Sunlight
Photosynthesis
Cellular respiration
Heat
–Respiration & Photosynthesis are Related
Energy to Drive Metabolism
HETEROTROPHS ConsumersAUTOTROPHS Producers
Harvest sunlight Convert solar energy into chemical energyExamples of autotrophs
PlantsAlgaeCyanobacteria
Increasingenergy
Increasingwavelength
0.1 nm 1 nm 10 nm 1000 nm 0.1 cm 1 cm 1 m 100 m
Gamma raysUV
lightX
raysInfrared
Radio waves
400 nm 430 nm 500 nm 560 nm 600 nm 650 nm 740 nm
Visible light
Electromagnetic Spectrum
Wavelength (nm)400 450 500 550 600 650 700
Am
ou
nt
of
lig
ht
abso
rpti
on
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Chlorophyll aChlorophyll b
Carotenoid
Absorption Spectrum of Photosynthetic PigmentsChlorophyll a, Chlorophyll b & Carotenoids
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Photosynthesis is a redox process
CO2 is reduced
H2O is oxidized
Reduction
Oxidation
6 O26 CO2 6 H2O C6H12O6
Photosynthesis Equation
Fig. 10.6b (TEArt) Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Chloroplast Structure
Thylakoid
Granum
Stroma
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Location of PhotosynthesisCarbon Dioxide Used & Sugar Produced
Water Used & Oxygen Produced
CO2
H20
Stroma
Thylakoid
Reactions of Photosynthesis
Light Harvesting
Light-Dependent Reactions
O2
Carbohydrates
ADP NADPHATP NADP+
Light Independent
Reactions
Sugar Building
Calvin Cycle
Fig. 10.6a (TEArt)
Chlorophyll moleculesand Carotenoidsin light-harvestingprotein complex
Thylakoidmembrane
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Photosynthesis: Light Harvesting by Photosystems
Reaction Center Chlorophyll
Sun
Fig. 10.10 (TEArt)
ElectronAcceptor
Photon
Chlorophyllmolecules
Photosystem
e-
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Reactioncenter
chlorophyll
Photosynthesis: Light Harvesting by Photosystems
e-
Fig. 10.6b (TEArt) Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Thylakoid Structure
Thylakoid
Fig. 10.16b (TEArt)
Photosystem II b6-f complex ATP synthase
H+Photon
Stroma
Thylakoidspace
Q
H2O
ATPADP
e-
H+
H+
H+H+H+
H+2H+12 02
_
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Stroma
Chemiosomosis & ATP Synthesis in Chloroplasts
Fig. 10.14 (TEArt)
Water-splittingenzyme
Photon
Photon
Ferredoxin
Plastoquinone
Photosystem II
NADP+ + H+
b6-fcomplex
NADPreductase
b6-f complex
Photosystem I NADP reductase
H2O2H+ + O2
H+
pC
Q
P700
P680
NADPH
Fd
Reactioncenter
e–
Plastocyanin
12
Excitedreactioncenter
e– e–
e–
En
erg
y o
f el
ectr
on
s Reactioncenter
__
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Photosynthesis: Light Harvesting by Photosystems
Figure 7.8B
e–
ATP
Photon
Photon
Photosystem II Photosystem I
NADPHe–
e– e–
e–
e–
e–
Light Reactions Mechanical Analogy
H2O provides electrons electron transport chainreduce NADPHATP synthesized
Oxygen released
H2O
O2 e-
Summary of Light Harvesting Reactions
1. H2O provides electrons for electron transport chains
2. NADP reduced to NADPH
3. ATP synthesized by chemiosmosis
4. Oxygen released
1. Fixation 2. Reduction 3. Regeneration
Sugar Building – The Calvin Cycle1 2 3
CO2P
Glucose
NADPH
ATP
Glyceraldehyde3-phosphate
RuBP 3-phosphoglycerate
Glyceraldehyde3-phosphate
RuBP
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
PHOTOSYNTHESIS REVIEW
Figure 7.11
Light H2O CO2
NADP+
Photosystem II
Photosystem I
Light Reactions
ADP
P+
RUBP
CALVINCYCLE
3-PGA
Stroma
G3PNADPH
ATP
O2Sugars
Cellular respiration
Cellulose
Starch
Other organiccompounds
Thylakoidmembranes
ChloroplastReactants
Products
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
CO2
H2O
Glucose
O2
ATP
Sunlight
Heat
Importance of Photosynthesis
Photosynthesis
Cellular respiration