Download CHO O HO COOH OH O

Bits of Photsynthesis
Plant Physiology
Biology UNI
2008
Plant job description
light
sugar
CO2
O2
H2O
The good stuff?
The good stuff?
GGP
P
Phytoene
-carotene
CH2OPP
CH2OPP
synthase
IPP
desaturase
desaturase
-carotene cyclase
Lycopene
cyclase
hydroxylase
Lutein
-carotene
hydroxylase
OH
ZeaxanthinOH
HO
OH
CHO
Retinal
epoxidase
HO
O
HO
CH2OH
O
O
Astaxanthin
O
HO
Retinol
dioxygenase
ABA
COOH
Retinoic Acid
Violaxanthin
OH
OH
O
O
COOH
HO
CHO
Xanthoxin
Chlorophyll fluorescence dumps
excess energy from absorbed light
Blue light shined on this green tissue,
red fluorescence from chlorophyll.
Photosystem geometry
Light harvesting complex =
Rxn center + Antenna pigs
Reaction center
Antenna Pigments
Shade and sun plants
Shade plant
Sun plant
Genetic control (capacity)
and developmental control.
May not be able to adjust
later.
Photosynthetic electron flow
Thylakoid
membrane
H+
NADPH
PS II
PS I
Coupling
factor
e-
eH+
H+
H2O
ATP
e-
e-
O2
ADP
+ Pi
H2O
split
3 H+
Cytochrome complex
Water splitting complex
The PQ “pump”
+
+
stroma
-
-
from PS II
+ +
-
-
thylakoid membrane
-
-
to PS I
PQ: plastoquinone
+
+
interior of thylakoid
Used electron power to move protons (charge battery)
Balanced photosynthesis
High energy
compounds
Photo
Synthesis
Real
time
Harvests light
energy
Uses harvested
energy
Unbalanced photosynthesis
High energy
compounds
Synthesis
Photo
Real
time
bright light produces
lots of energy
low-capacity
biochemical pathways
use it slowly
Potential for destruction.