Slide 1

Figure 7.1Page 111

Slide 2

Carbon dioxide,

water are required

Carbon dioxide,

water are released

Oxygen is released

Oxygen is

required

1) Water is split by light energy. Oxygen

escapes. Coenzymes pick up electrons, H+.

2)  ATP energy drives synthesis of glucose from hydrogen and electrons, plus carbon and oxygen (from CO2).

ATP is available to drive cellular tasks

1) Glucose is degraded to CO2 and water. Coenzymes pick up electrons, hydrogen.

2)  Coenzymes give up electrons, hydrogen to oxygen-requiring transfer chains that release energy to drive ATP formation.

Figure 7.2Page 112

Slide 3

12H2O + 6CO2 6O2 + C2H12O6 + 6H2O

Water Carbon Dioxide

Oxygen Glucose Water

In-text figurePage 115

Slide 4

(see next slide)

upper leaf surface photosynthetic cells

Cutaway section of leaf

Stepped Art

Figure 7.3b,cPage 116

Slide 5

two outer membranes

inner membrane system(thylakoids connected by channels)

stroma

channel (see next slide)

stacked part of thylakoid membrane

Stepped Art

Figure 7.3d,ePage 116

Slide 6

CO2 H2O

carbohydrate end product(e.g., sucrose, starch, cellulose)

Light-Independent Reactions

glucoseP

ADP + Pi

ATP

NADPHNADP+

e–

H+

H+

H+ H+

H+

O

H+

compartment inside a thylakoidH2O

SUNLIGHT

Figure 7.3fPage 117

Slide 7

Products 6O2 C6H12O6 6H2O

Stepped Art

In-text figurePage 116

Reactants 12H2O 6CO2

Slide 8

sunlight water uptake carbon dioxide uptake

ATP

ADP + Pi

NADPH

NAD+

glucoseP

oxygen release

LIGHT INDEPENDENT

REACTIONS

LIGHT DEPENDENT REACTIONS

new water

In-text figurePage 117

Slide 9

nutrient cycling

energy output (mainly heat)

energy input

from sun

Heterotrophs(consumers, decomposers)

Photoautotrophs(plants, other producers)

Figure 7.4Page 118

Slide 10

High energy wavelength

Low energy wavelength

In-text figurePage 118

Slide 11

Wavelength of light (nanometers)

Figure 7.5aPage 118

Slide 12

per

cen

t o

f w

avel

eng

ths

abso

rbed

per

cen

t o

f w

avel

eng

ths

abso

rbed

wavelengths (nanometers)wavelengths (nanometers)

chlorophyll b

chlorophyll a

beta-carotenephycoerythrin (a phycobilin)

Figure 7.6a,bPage 119

Slide 13

chlorophyll b

chlorophyll a

carotenoids

phycoerythrin (a phycobilin)

(combined absorption efficiency across entire visible spectrum)

chlorophyll a

chlorophyll b

phycoerythrin (a phycobilin)

Figure 7.6cPage 119

Slide 14

Chlorophyll a

Beta-carotene

Figure 7.7Page 120

Slide 15

water-splitting complex thylakoid compartment

H2O 2H + 1/2O2

P680

acceptor

P700

acceptorpool of

electron carriers

stromaPHOTOSYSTEM II (light green)

PHOTOSYSTEM I (light green)

Figure 7.10Page 121

Slide 16

reaction center

incoming light

PHOTOSYSTEM

Figure 7.11Page 122

Slide 17

Electron flow through transfer chain sets up conditions for ATP

formation at other membrane sites.

electron acceptor electron

transferchain

e–

e–

e–

e–

ATP

Figure 7.12Page 122

Slide 18

sunlight

photolysis

THYLAKOID COMPARTMENT

second electron transfer chain

H2O

NADP+ NADPH

e–

ATP

ATP SYNTHASE

PHOTOSYSTEM IPHOTOSYSTEM II ADP + Pi

e–

first electron transfer chain

STROMA

Figure 7.13aPage 123

Slide 19

Po

ten

tial

to

tra

nsf

er e

ner

gy

(vo

ids)

H2O 1/2 O2 + 2H+

(Photosystem II)

(Photosystem I)

e– e–

e–e–

secondtransfer

chain

NADPHfirst

transferchain

Figure 7.13bPage 123

Slide 20

ADP + Pi

ATP SYNTHASE

Gradients propel H+ through ATP synthases;ATP forms by phosphate-group transfer

ATP

H+ is shunted across membrane by some components of the first electron transfer chain

PHOTOSYSTEM II

H2Oe–

acceptor

Photolysis in the thylakoid compartment splits water

Stepped Art

Figure 7.15Page 124

Slide 21

12

12 NADPH

12PGAL

12 ADP12 Pi

12 NADP+

ATP

CARBON FIXATION6 CO2

66

RuBPunstable intermediate

ATP

6 ADP

6

4 Pi

P

10

glucose

PGAL2

Pi

P

PGAL

12PGA

CALVIN-BENSON CYCLE

Stepped Art

Figure 7.16Page 125

Slide 22

Leaf cross-section from C3 plant

upper epidermis

palisade mesophyll

spongy mesophyll

lower epidermis

stoma veinair space

Figure 7.17aPage 126

Do not post on Internet

Slide 23

6 PGA + 6 glycolate

6 PGAL

1 PGAL

Twelve turns of the cycle required to make one 8-carbon sugar

RUBP

Calvin-Benson Cycle

6 CO2

+ water

5 PGAL

Stomata closed: CO2 can’t get in; O2 can’t get out

Rubisco binds oxygen, not carbon dioxide

X

Photorespiration in a C3 plant Figure 7.18aPage 127

Slide 24

upper epidermis

mesophyll

bundle-sheath cell

lower epidermis

vein stoma (with air space above)

Leaf cross-section from C4 plant

Figure 7.17bPage 126Do not post

on Internet

Slide 25

oxaloacetate

malate

C4 cycle

pyruvateCO2

12 PGA

10 PGAL

2 PGAL

1 sugar

RuBP Calvin-Benson Cycle

mesophyll cell

bundle-sheath cell

12 PGAL

PEP

Stomata closed: CO2 can’t get in; O2 can’t get out X C4 carbon fixation

Figure 7.18bPage 127

Slide 26

CO2 uptake at night only

C4 cycle

Calvin-Benson Cycle

C4 cycle operates at night when stomata are open

1 sugar

CO2 that accumulated during night is used during day for C3 cycle in same cell

CAM plant

Figure 7.19Page 127