Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Lec
ture
s by
Chr
is R
omer
o, u
pdat
ed b
y E
rin
Bar
ley
with
con
trib
utio
ns fr
om J
oan
Shar
p
Cha
pter
10
Cha
pter
10
Phot
osyn
thes
is
Ove
rvie
w: T
he P
roce
ss T
hat F
eeds
the
Bio
sphe
re
•Ph
otos
ynth
esis
is th
e pr
oces
s th
at c
onve
rts
sola
r ene
rgy
into
che
mic
al e
nerg
y
•D
irect
ly o
r ind
irect
ly, p
hoto
synt
hesi
s no
uris
hes
alm
ost t
he e
ntire
livi
ng w
orld
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
•A
utot
roph
s su
stai
n th
emse
lves
with
out e
atin
g an
ythi
ng d
eriv
ed fr
om o
ther
org
anis
ms
•A
utot
roph
s ar
e th
e pr
oduc
ers
of th
e bi
osph
ere,
pr
oduc
ing
orga
nic
mol
ecul
es fr
om C
O2
and
othe
r ino
rgan
ic m
olec
ules
•A
lmos
t all
plan
ts a
re p
hoto
auto
troph
s, u
sing
th
e en
ergy
of s
unlig
ht to
mak
e or
gani
c m
olec
ules
from
H2O
and
CO
2
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
You
shou
ld n
ow b
e ab
le to
:
1.D
escr
ibe
the
stru
ctur
e of
a c
hlor
opla
st
2.D
escr
ibe
the
rela
tions
hip
betw
een
an a
ctio
n sp
ectru
m a
nd a
n ab
sorp
tion
spec
trum
3.Tr
ace
the
mov
emen
t of e
lect
rons
in li
near
el
ectro
n flo
w
4.Tr
ace
the
mov
emen
t of e
lect
rons
in c
yclic
el
ectro
n flo
w
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
5.D
escr
ibe
the
sim
ilarit
ies
and
diffe
renc
es
betw
een
oxid
ativ
e ph
osph
oryl
atio
n in
m
itoch
ondr
ia a
nd p
hoto
phos
phor
ylat
ion
in
chlo
ropl
asts
6.D
escr
ibe
the
role
of A
TP a
nd N
AD
PH
in th
e C
alvi
n cy
cle
7.D
escr
ibe
the
maj
or c
onse
quen
ces
of
phot
ores
pira
tion
8.D
escr
ibe
two
impo
rtant
pho
tosy
nthe
tic
adap
tatio
ns th
at m
inim
ize
phot
ores
pira
tion
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Fig.
10-
1
•P
hoto
synt
hesi
s oc
curs
in p
lant
s, a
lgae
, cer
tain
ot
her p
rotis
ts, a
nd s
ome
prok
aryo
tes
•Th
ese
orga
nism
s fe
ed n
ot o
nly
them
selv
es b
ut
also
mos
t of t
he li
ving
wor
ld
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Fig.
10-
2
(a) P
lant
s
(c) U
nice
llula
r pro
tist
10 µ
m
1.5
µm
40 µ
m(d
) Cya
noba
cter
ia
(e) P
urpl
e su
lfur
bact
eria
(b) M
ultic
ellu
lar a
lga
Con
cept
10.
1: P
hoto
synt
hesi
s con
vert
s lig
ht e
nerg
y to
the
chem
ical
ene
rgy
of fo
od
•C
hlor
opla
sts
are
stru
ctur
ally
sim
ilar t
o an
d lik
ely
evol
ved
from
pho
tosy
nthe
tic b
acte
ria
•Th
e st
ruct
ural
org
aniz
atio
n of
thes
e ce
lls a
llow
s fo
r the
che
mic
al re
actio
ns o
f pho
tosy
nthe
sis
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Chl
orop
last
s: T
he S
ites o
f Pho
tosy
nthe
sis i
n Pl
ants
•Le
aves
are
the
maj
or lo
catio
ns o
f ph
otos
ynth
esis
•Th
eir g
reen
col
or is
from
chl
orop
hyll,
the
gree
n pi
gmen
t with
in c
hlor
opla
sts
•Li
ght e
nerg
y ab
sorb
ed b
y ch
loro
phyl
l driv
es th
e sy
nthe
sis
of o
rgan
ic m
olec
ules
in th
e ch
loro
plas
t
•C
O2
ente
rs a
nd O
2ex
its th
e le
af th
roug
h m
icro
scop
ic p
ores
cal
led
stom
ata
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
•C
hlor
opla
sts
are
foun
d m
ainl
y in
cel
ls o
f the
m
esop
hyll,
the
inte
rior t
issu
e of
the
leaf
•A
typi
cal m
esop
hyll
cell
has
30–4
0 ch
loro
plas
ts
•Th
e ch
loro
phyl
l is
in th
e m
embr
anes
of
thyl
akoi
ds (c
onne
cted
sac
s in
the
chlo
ropl
ast);
th
ylak
oids
may
be
stac
ked
in c
olum
ns c
alle
d gr
ana
•C
hlor
opla
sts
also
con
tain
str
oma,
a d
ense
flui
d
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Fig.
10-
3Le
af c
ross
sec
tion
Vein
Mes
ophy
ll
Stom
ata
CO
2O
2
Chl
orop
last
Mes
ophy
ll ce
ll
Out
erm
embr
ane
Inte
rmem
bran
esp
ace
5 µm
Inne
rm
embr
ane
Thyl
akoi
dsp
ace
Thyl
akoi
d
Gra
num
Stro
ma
1 µm
Tra
ckin
g A
tom
s Thr
ough
Pho
tosy
nthe
sis:
Sc
ient
ific
Inqu
iry
•P
hoto
synt
hesi
s ca
n be
sum
mar
ized
as
the
follo
win
g eq
uatio
n:
6 C
O2
+ 12
H2O
+ L
ight
ene
rgy o
C6H
12O
6+
6 O
2+
6 H
2O
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
The
Split
ting
of W
ater
•C
hlor
opla
sts
split
H2O
into
hyd
roge
n an
d ox
ygen
, inc
orpo
ratin
g th
e el
ectro
ns o
f hy
drog
en in
to s
ugar
mol
ecul
es
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Rea
ctan
ts:
Fig.
10-
4
6 C
O2
Prod
ucts
:
12 H
2O
6 O
26
H2O
C6H
12O
6
Phot
osyn
thes
is a
s a R
edox
Pro
cess
•P
hoto
synt
hesi
s is
a re
dox
proc
ess
in w
hich
H
2O is
oxi
dize
d an
d C
O2
is re
duce
d
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
The
Tw
o St
ages
of P
hoto
synt
hesi
s: A
Pre
view
•P
hoto
synt
hesi
s co
nsis
ts o
f the
ligh
t rea
ctio
ns
(the
phot
opa
rt) a
nd C
alvi
n cy
cle
(the
synt
hesi
spa
rt)
•Th
e lig
ht re
actio
ns (i
n th
e th
ylak
oids
):–
Spl
it H
2O–
Rel
ease
O2
–R
educ
e N
AD
P+to
NA
DP
H–
Gen
erat
e A
TP fr
om A
DP
by
phot
opho
spho
ryla
tion
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
•Th
e C
alvi
n cy
cle
(in th
e st
rom
a) fo
rms
suga
r fro
m C
O2,
usin
g A
TP a
nd N
AD
PH
•Th
e C
alvi
n cy
cle
begi
ns w
ith c
arbo
n fix
atio
n,
inco
rpor
atin
g C
O2
into
org
anic
mol
ecul
es
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Ligh
t
Fig.
10-
5-1
H2O
Chl
orop
last
Ligh
tR
eact
ions
NA
DP+ P
AD
P i+
Ligh
t
Fig.
10-
5-2
H2O
Chl
orop
last
Ligh
tR
eact
ions
NA
DP+ P
AD
P i+ AT
P
NA
DPH
O2
Ligh
t
Fig.
10-
5-3
H2O
Chl
orop
last
Ligh
tR
eact
ions
NA
DP+ P
AD
P i+ AT
P
NA
DPH
O2
Cal
vin
Cyc
le
CO
2
Ligh
t
Fig.
10-
5-4
H2O
Chl
orop
last
Ligh
tR
eact
ions
NA
DP+ P
AD
P i+ AT
P
NA
DPH
O2
Cal
vin
Cyc
le
CO
2
[CH
2O]
(sug
ar)
Con
cept
10.
2: T
he li
ght r
eact
ions
con
vert
sola
r en
ergy
to th
e ch
emic
al e
nerg
y of
AT
P an
d N
AD
PH
•C
hlor
opla
sts
are
sola
r-pow
ered
che
mic
al
fact
orie
s
•Th
eir t
hyla
koid
s tra
nsfo
rm li
ght e
nerg
y in
to th
e ch
emic
al e
nerg
y of
ATP
and
NA
DP
H
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
The
Nat
ure
of S
unlig
ht
•Li
ght i
s a
form
of e
lect
rom
agne
tic e
nerg
y, a
lso
calle
d el
ectro
mag
netic
radi
atio
n
•Li
ke o
ther
ele
ctro
mag
netic
ene
rgy,
ligh
t tra
vels
in
rhyt
hmic
wav
es
•W
avel
engt
h is
the
dist
ance
bet
wee
n cr
ests
of
wav
es
•W
avel
engt
h de
term
ines
the
type
of
elec
trom
agne
tic e
nerg
y
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
•Th
e el
ectr
omag
netic
spe
ctru
m is
the
entir
e ra
nge
of e
lect
rom
agne
tic e
nerg
y, o
r rad
iatio
n
•Vi
sibl
e lig
ht c
onsi
sts
of w
avel
engt
hs (i
nclu
ding
th
ose
that
driv
e ph
otos
ynth
esis
) tha
t pro
duce
co
lors
we
can
see
•Li
ght a
lso
beha
ves
as th
ough
it c
onsi
sts
of
disc
rete
par
ticle
s, c
alle
d ph
oton
s
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
UV
Fig.
10-
6
Visi
ble
light
Infr
ared
Mic
ro-
wav
esR
adio
wav
esX-
rays
Gam
ma
rays
103
m1
m(1
09nm
)10
6nm
103
nm1
nm10
–3 n
m10
–5 n
m
380
450
500
550
600
650
700
750
nm
Long
er w
avel
engt
hLo
wer
ene
rgy
Hig
her e
nerg
ySh
orte
r wav
elen
gth
Phot
osyn
thet
ic P
igm
ents
: The
Lig
ht R
ecep
tors
•P
igm
ents
are
sub
stan
ces
that
abs
orb
visi
ble
light
•D
iffer
ent p
igm
ents
abs
orb
diffe
rent
w
avel
engt
hs
•W
avel
engt
hs th
at a
re n
ot a
bsor
bed
are
refle
cted
or t
rans
mitt
ed
•Le
aves
app
ear g
reen
bec
ause
chl
orop
hyll
refle
cts
and
trans
mits
gre
en li
ght
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Fig.
10-
7
Ref
lect
edlig
ht
Abs
orbe
dlig
ht
Ligh
t
Chl
orop
last
Tran
smitt
edlig
ht
Gra
num
•A
spe
ctro
phot
omet
er m
easu
res
a pi
gmen
t’s
abilit
y to
abs
orb
vario
us w
avel
engt
hs
•Th
is m
achi
ne s
ends
ligh
t thr
ough
pig
men
ts a
nd
mea
sure
s th
e fra
ctio
n of
ligh
t tra
nsm
itted
at
each
wav
elen
gth
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Fig.
10-
8
Gal
vano
met
er
Slit
mov
es to
pass
ligh
tof
sel
ecte
dw
avel
engt
h
Whi
telig
ht
Gre
enlig
ht
Blu
elig
ht
The
low
tran
smitt
ance
(hig
h ab
sorp
tion)
read
ing
indi
cate
s th
atch
loro
phyl
l abs
orbs
mos
t blu
e lig
ht.
The
high
tran
smitt
ance
(low
abs
orpt
ion)
read
ing
indi
cate
s th
atch
loro
phyl
l abs
orbs
very
littl
e gr
een
light
.
Ref
ract
ing
pris
mPh
otoe
lect
rictu
beC
hlor
ophy
llso
lutio
n
TEC
HN
IQU
E
12
3
4
•A
n ab
sorp
tion
spec
trum
is a
gra
ph p
lotti
ng a
pi
gmen
t’s li
ght a
bsor
ptio
n ve
rsus
wav
elen
gth
•Th
e ab
sorp
tion
spe
ctru
m o
f chl
orop
hyll a
sugg
ests
that
vio
let-b
lue
and
red
light
wor
k be
st fo
r pho
tosy
nthe
sis
•A
n ac
tion
spec
trum
pro
files
the
rela
tive
effe
ctiv
enes
s of
diff
eren
t wav
elen
gths
of
radi
atio
n in
driv
ing
a pr
oces
s
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Fig.
10-
9
Wav
elen
gth
of li
ght (
nm)
(b) A
ctio
n sp
ectr
um
(a) A
bsor
ptio
n sp
ectr
a
(c) E
ngel
man
n’s
expe
rimen
t
Aer
obic
bac
teria
RES
ULT
S
Fila
men
tof
alg
a
Chl
oro-
phyl
l aC
hlor
ophy
ll b
Car
oten
oids
500
400
600
700
700
600
500
400
•Th
e ac
tion
spec
trum
of p
hoto
synt
hesi
s w
as
first
dem
onst
rate
d in
188
3 by
The
odor
W.
Eng
elm
ann
•In
his
exp
erim
ent,
he e
xpos
ed d
iffer
ent
segm
ents
of a
fila
men
tous
alg
a to
diff
eren
t w
avel
engt
hs
•A
reas
rece
ivin
g w
avel
engt
hs fa
vora
ble
to
phot
osyn
thes
is p
rodu
ced
exce
ss O
2
•H
e us
ed th
e gr
owth
of a
erob
ic b
acte
ria
clus
tere
d al
ong
the
alga
as
a m
easu
re o
f O2
prod
uctio
nC
opyr
ight
© 2
008
Pear
son
Educ
atio
n, In
c., p
ublis
hing
as P
ears
on B
enja
min
Cum
min
gs
•C
hlor
ophy
ll a
is th
e m
ain
phot
osyn
thet
ic
pigm
ent
•A
cces
sory
pig
men
ts, s
uch
as c
hlor
ophy
ll b,
br
oade
n th
e sp
ectru
m u
sed
for p
hoto
synt
hesi
s
•A
cces
sory
pig
men
ts c
alle
d ca
rote
noid
s ab
sorb
exc
essi
ve li
ght t
hat w
ould
dam
age
chlo
roph
yll
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Fig.
10-
10
Porp
hyrin
ring
:lig
ht-a
bsor
bing
“hea
d” o
f mol
ecul
e;no
te m
agne
sium
atom
at c
ente
r
in c
hlor
ophy
ll a
CH
3
Hyd
roca
rbon
tail:
inte
ract
s w
ith h
ydro
phob
icre
gion
s of
pro
tein
s in
side
thyl
akoi
d m
embr
anes
of
chlo
ropl
asts
; H a
tom
s no
tsh
ownC
HO
in c
hlor
ophy
ll b
Exc
itatio
n of
Chl
orop
hyll
by L
ight
•W
hen
a pi
gmen
t abs
orbs
ligh
t, it
goes
from
a
grou
nd s
tate
to a
n ex
cite
d st
ate,
whi
ch is
un
stab
le
•W
hen
exci
ted
elec
trons
fall
back
to th
e gr
ound
st
ate,
pho
tons
are
giv
en o
ff, a
n af
terg
low
cal
led
fluor
esce
nce
•If
illum
inat
ed, a
n is
olat
ed s
olut
ion
of c
hlor
ophy
ll w
ill flu
ores
ce, g
ivin
g of
f lig
ht a
nd h
eat
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Fig.
10-
11
(a) E
xcita
tion
of is
olat
ed c
hlor
ophy
ll m
olec
ule
Hea
t
Exci
ted
stat
e
(b) F
luor
esce
nce
Phot
onG
roun
dst
atePh
oton
(fluo
resc
ence
)
Energy of electron
e–
Chl
orop
hyll
mol
ecul
e
A P
hoto
syst
em: A
Rea
ctio
n-C
ente
r C
ompl
ex
Ass
ocia
ted
with
Lig
ht-H
arve
stin
g C
ompl
exes
•A
pho
tosy
stem
con
sist
s of
a re
actio
n-ce
nter
co
mpl
ex (a
type
of p
rote
in c
ompl
ex)
surro
unde
d by
ligh
t-har
vest
ing
com
plex
es
•Th
e lig
ht-h
arve
stin
g co
mpl
exes
(pig
men
t m
olec
ules
bou
nd to
pro
tein
s) fu
nnel
the
ener
gy
of p
hoto
ns to
the
reac
tion
cent
er
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
•A
prim
ary
elec
tron
acc
epto
r in
the
reac
tion
cent
er a
ccep
ts a
n ex
cite
d el
ectro
n fro
m
chlo
roph
yll a
•S
olar
-pow
ered
tran
sfer
of a
n el
ectro
n fro
m a
ch
loro
phyl
l a m
olec
ule
to th
e pr
imar
y el
ectro
n ac
cept
or is
the
first
ste
p of
the
light
reac
tions
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Fig.
10-
12
THYL
AK
OID
SPA
CE
(INTE
RIO
R O
F TH
YLA
KO
ID)
STR
OM
A
e–
Pigm
ent
mol
ecul
es
Phot
on
Tran
sfer
of e
nerg
ySp
ecia
l pai
r of
chlo
roph
yll a
mol
ecul
es
Thylakoid membrane
Phot
osys
tem
Prim
ary
elec
tron
acce
ptor
Rea
ctio
n-ce
nter
com
plex
Ligh
t-har
vest
ing
com
plex
es
•Th
ere
are
two
type
s of
pho
tosy
stem
s in
the
thyl
akoi
d m
embr
ane
•Ph
otos
yste
m II
(PS
II) fu
nctio
ns fi
rst (
the
num
bers
refle
ct o
rder
of d
isco
very
) and
is b
est a
t ab
sorb
ing
a w
avel
engt
h of
680
nm
•Th
e re
actio
n-ce
nter
chl
orop
hyll
aof
PS
II is
ca
lled
P68
0
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
•Ph
otos
yste
m I
(PS
I) is
bes
t at a
bsor
bing
a
wav
elen
gth
of 7
00 n
m
•Th
e re
actio
n-ce
nter
chl
orop
hyll
aof
PS
I is
ca
lled
P70
0
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Lin
ear
Ele
ctro
n Fl
ow
•D
urin
g th
e lig
ht re
actio
ns, t
here
are
two
poss
ible
rout
es fo
r ele
ctro
n flo
w: c
yclic
and
lin
ear
•Li
near
ele
ctro
n flo
w, t
he p
rimar
y pa
thw
ay,
invo
lves
bot
h ph
otos
yste
ms
and
prod
uces
ATP
an
d N
AD
PH
usi
ng li
ght e
nerg
y
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
•A
pho
ton
hits
a p
igm
ent a
nd it
s en
ergy
is
pass
ed a
mon
g pi
gmen
t mol
ecul
es u
ntil
it ex
cite
s P
680
•A
n ex
cite
d el
ectro
n fro
m P
680
is tr
ansf
erre
d to
th
e pr
imar
y el
ectro
n ac
cept
or
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Pigm
ent
mol
ecul
es
Ligh
t
P680
e–2
1
Fig.
10-
13-1
Phot
osys
tem
II(P
S II)
Prim
ary
acce
ptor
•P
680+
(P68
0 th
at is
mis
sing
an
elec
tron)
is a
ve
ry s
trong
oxi
dizi
ng a
gent
•H
2O is
spl
it by
enz
ymes
, and
the
elec
trons
are
tra
nsfe
rred
from
the
hydr
ogen
ato
ms
to P
680+
, th
us re
duci
ng it
to P
680
•O
2is
rele
ased
as
a by
-pro
duct
of t
his
reac
tion
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Pigm
ent
mol
ecul
es
Ligh
t
P680
e–
Prim
ary
acce
ptor
2
1
e– e–
2 H
+
O2
+3H
2O
1 / 2Fig.
10-
13-2
Phot
osys
tem
II(P
S II)
•E
ach
elec
tron
“falls
” dow
n an
ele
ctro
n tra
nspo
rt ch
ain
from
the
prim
ary
elec
tron
acce
ptor
of P
S
II to
PS
I
•E
nerg
y re
leas
ed b
y th
e fa
ll dr
ives
the
crea
tion
of a
pro
ton
grad
ient
acr
oss
the
thyl
akoi
d m
embr
ane
•D
iffus
ion
of H
+(p
roto
ns) a
cros
s th
e m
embr
ane
driv
es A
TP s
ynth
esis
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Pigm
ent
mol
ecul
es
Ligh
t
P680
e–
Prim
ary
acce
ptor
2
1
e– e–
2 H
+
O2
+3H
2O
1 / 2
4
Pq
Pc
Cyt
ochr
ome
com
plex
5
ATP
Fig.
10-
13-3
Phot
osys
tem
II(P
S II)
•In
PS
I (li
ke P
S II
), tra
nsfe
rred
ligh
t ene
rgy
exci
tes
P70
0, w
hich
lose
s an
ele
ctro
n to
an
elec
tron
acce
ptor
•P
700+
(P70
0 th
at is
mis
sing
an
elec
tron)
ac
cept
s an
ele
ctro
n pa
ssed
dow
n fro
m P
S II
vi
a th
e el
ectro
n tra
nspo
rt ch
ain
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Pigm
ent
mol
ecul
es
Ligh
t
P680
e–
Prim
ary
acce
ptor
2
1
e– e–
2 H
+
O2
+3H
2O
1 / 2
4
Pq
Pc
Cyt
ochr
ome
com
plex
5
ATP
Phot
osys
tem
I(P
S I)
Ligh
t
Prim
ary
acce
ptor
e–
P700
6
Fig.
10-
13-4
Phot
osys
tem
II(P
S II)
•E
ach
elec
tron
“falls
” dow
n an
ele
ctro
n tra
nspo
rt ch
ain
from
the
prim
ary
elec
tron
acce
ptor
of P
S
I to
the
prot
ein
ferr
edox
in (F
d)
•Th
e el
ectro
ns a
re th
en tr
ansf
erre
d to
NA
DP
+
and
redu
ce it
to N
AD
PH
•Th
e el
ectro
ns o
f NA
DP
H a
re a
vaila
ble
for t
he
reac
tions
of t
he C
alvi
n cy
cle
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Pigm
ent
mol
ecul
es
Ligh
t
P680
e–
Prim
ary
acce
ptor
2
1
e– e–
2 H
+
O2
+3H
2O
1 / 2
4
Pq
Pc
Cyt
ochr
ome
com
plex
5
ATP
Phot
osys
tem
I(P
S I)
Ligh
t
Prim
ary
acce
ptor
e–
P700
6
Fd
NA
DP+
redu
ctas
e
NA
DP+
+ H
+
NA
DPH
8
7
e–e– 6
Fig.
10-
13-5
Phot
osys
tem
II(P
S II)
NA
D+
as a
n el
ectr
on s
huttl
e
PN
AD
P+
(E°’
gege
nübe
rN
AD
+ u
nver
ände
rt)
Fig.
10-
14
Mill
mak
esAT
P
e– NA
DPH
e–e–
e–
e–
e–AT
P
Phot
osys
tem
IIPh
otos
yste
m I
e–
Cyc
lic E
lect
ron
Flow
•C
yclic
ele
ctro
n flo
w u
ses
only
pho
tosy
stem
I
and
prod
uces
ATP
, but
not
NA
DP
H
•C
yclic
ele
ctro
n flo
w g
ener
ates
sur
plus
ATP
, sa
tisfy
ing
the
high
er d
eman
d in
the
Cal
vin
cycl
e
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Fig.
10-
15
ATP
Phot
osys
tem
II
Phot
osys
tem
I
Prim
ary
acce
ptor
Pq
Cyt
ochr
ome
com
plexFd
Pc
Prim
ary
acce
ptor
Fd
NA
DP+
redu
ctas
eN
AD
PH
NA
DP+
+ H
+
•S
ome
orga
nism
s su
ch a
s pu
rple
sul
fur b
acte
ria
have
PS
I bu
t not
PS
II
•C
yclic
ele
ctro
n flo
w is
thou
ght t
o ha
ve e
volv
ed
befo
re li
near
ele
ctro
n flo
w
•C
yclic
ele
ctro
n flo
w m
ay p
rote
ct c
ells
from
lig
ht-in
duce
d da
mag
e
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
A C
ompa
riso
n of
Che
mio
smos
is in
Chl
orop
last
s an
d M
itoch
ondr
ia
•C
hlor
opla
sts
and
mito
chon
dria
gen
erat
e A
TP
by c
hem
iosm
osis
, but
use
diff
eren
t sou
rces
of
ener
gy
•M
itoch
ondr
ia tr
ansf
er c
hem
ical
ene
rgy
from
fo
od to
ATP
; chl
orop
last
s tra
nsfo
rm li
ght
ener
gy in
to th
e ch
emic
al e
nerg
y of
ATP
•S
patia
l org
aniz
atio
n of
che
mio
smos
is d
iffer
s be
twee
n ch
loro
plas
ts a
nd m
itoch
ondr
ia b
ut
also
sho
ws
sim
ilarit
ies
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
•In
mito
chon
dria
, pro
tons
are
pum
ped
to th
e in
term
embr
ane
spac
e an
d dr
ive
ATP
syn
thes
is
as th
ey d
iffus
e ba
ck in
to th
e m
itoch
ondr
ial
mat
rix
•In
chl
orop
last
s, p
roto
ns a
re p
umpe
d in
to th
e th
ylak
oid
spac
e an
d dr
ive
ATP
syn
thes
is a
s th
ey d
iffus
e ba
ck in
to th
e st
rom
a
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Fig.
10-
16
Key
Mito
chon
drio
nC
hlor
opla
st
CH
LOR
OPL
AST
STR
UC
TUR
EM
ITO
CH
ON
DR
ION
STR
UC
TUR
E
Inte
rmem
bran
esp
ace
Inne
rm
embr
ane
Elec
tron
tran
spor
tch
ain
H+
Diff
usio
n
Mat
rix
Hig
her [
H+ ]
Low
er [H
+ ]
Stro
ma
ATP
synt
hase
AD
P +
Pi
H+
ATP
Thyl
akoi
dsp
ace
Thyl
akoi
dm
embr
ane
•A
TP a
nd N
AD
PH
are
pro
duce
d on
the
side
fa
cing
the
stro
ma,
whe
re th
e C
alvi
n cy
cle
take
s pl
ace
•In
sum
mar
y, li
ght r
eact
ions
gen
erat
e A
TP a
nd
incr
ease
the
pote
ntia
l ene
rgy
of e
lect
rons
by
mov
ing
them
from
H2O
to N
AD
PH
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Fig.
10-
17
Ligh
t
Fd
Cyt
ochr
ome
com
plex
AD
P + i
H+
ATP
P
ATP
synt
hase
ToC
alvi
nC
ycle
STR
OM
A(lo
w H
+co
ncen
trat
ion)
Thyl
akoi
dm
embr
ane
THYL
AK
OID
SPA
CE
(hig
h H
+co
ncen
trat
ion)
STR
OM
A(lo
w H
+co
ncen
trat
ion)
Phot
osys
tem
IIPh
otos
yste
m I
4 H
+
4 H
+
Pq
Pc
Ligh
tN
AD
P+re
duct
ase
NA
DP+
+ H
+
NA
DPH
+2 H
+
H2O
O2
e–e–
1 / 21
2
3
Con
cept
10.
3: T
he C
alvi
n cy
cle
uses
AT
P an
d N
AD
PH to
con
vert
CO
2to
suga
r
•Th
e C
alvi
n cy
cle,
like
the
citri
c ac
id c
ycle
, re
gene
rate
s its
sta
rting
mat
eria
l afte
r m
olec
ules
ent
er a
nd le
ave
the
cycl
e
•Th
e cy
cle
build
s su
gar f
rom
sm
alle
r mol
ecul
es
by u
sing
ATP
and
the
redu
cing
pow
er o
f el
ectro
ns c
arrie
d by
NA
DP
H
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
•C
arbo
n en
ters
the
cycl
e as
CO
2an
d le
aves
as
a su
gar n
amed
gly
cera
ldeh
yde-
3-ph
ospa
te
(G3P
)
•Fo
r net
syn
thes
is o
f 1 G
3P, t
he c
ycle
mus
t tak
e pl
ace
thre
e tim
es, f
ixin
g 3
mol
ecul
es o
f CO
2
•Th
e C
alvi
n cy
cle
has
thre
e ph
ases
:–
Car
bon
fixat
ion
(cat
alyz
ed b
y ru
bisc
o)–
Red
uctio
n–
Reg
ener
atio
n of
the
CO
2ac
cept
or (R
uBP)
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Fig.
10-
18-1
Rib
ulos
e bi
spho
spha
te(R
uBP)
3-Ph
osph
ogly
cera
te
Shor
t-liv
edin
term
edia
te
Phas
e 1:
Car
bon
fixat
ion
(Ent
erin
g on
eat
a ti
me)
Rub
isco
Inpu
tC
O2
P
36
3
3
P
PP
P
Fig.
10-
18-2
Rib
ulos
e bi
spho
spha
te(R
uBP)
3-Ph
osph
ogly
cera
te
Shor
t-liv
edin
term
edia
te
Phas
e 1:
Car
bon
fixat
ion
(Ent
erin
g on
eat
a ti
me)
Rub
isco
Inpu
tC
O2
P
36
3
3
P
PP
P
ATP
6
6 A
DP
PP
61,
3-B
isph
osph
ogly
cera
te
6
P
P6
66
NA
DP+NA
DPH
i
Phas
e 2:
Red
uctio
nG
lyce
rald
ehyd
e-3-
phos
phat
e(G
3P)
1P
Out
put
G3P
(a s
ugar
)
Glu
cose
and
othe
r org
anic
com
poun
ds
Cal
vin
Cyc
le
Fig.
10-
18-3
Rib
ulos
e bi
spho
spha
te(R
uBP)
3-Ph
osph
ogly
cera
te
Shor
t-liv
edin
term
edia
te
Phas
e 1:
Car
bon
fixat
ion
(Ent
erin
g on
eat
a ti
me)
Rub
isco
Inpu
tC
O2
P
36
3
3
P
PP
P
ATP
6
6 A
DP
PP
61,
3-B
isph
osph
ogly
cera
te
6
P
P6
66
NA
DP+NA
DPH
i
Phas
e 2:
Red
uctio
nG
lyce
rald
ehyd
e-3-
phos
phat
e(G
3P)
1P
Out
put
G3P
(a s
ugar
)
Glu
cose
and
othe
r org
anic
com
poun
ds
Cal
vin
Cyc
le3
3 A
DP
ATP
5P
Phas
e 3:
Reg
ener
atio
n of
the
CO
2ac
cept
or(R
uBP)
G3P
Cal
vin-
Zykl
us1.
Pha
se: C
O2-
Fixi
erun
g3x
3x6x
Cal
vin-
Zykl
us1.
Pha
se: C
O2-
Fixi
erun
g
Rub
isco
: Ribul
ose-Bis
phos
phat
Car
boxy
lase
Oxy
gena
se
3x R
ibul
ose-
Bis
phos
phat
3x C
O2
+ 3x
H2O
CH
2O O OH
HO
HH
CH
2O
P P
6x P
hosp
hogl
ycer
at
CO
OH OH
H
CH
2OP
Cal
vin-
Zykl
us2.
Pha
se: R
eduk
tion
3x
3x6x
6x
6x
5xfü
r 3. P
hase
1x fü
r Stä
rkeb
iosy
nthe
se
ATP
NAD
PH+
H+
ADP
NAD
P+
Cal
vin-
Zykl
us2.
Pha
se: R
eduk
tion
CO
OH OH
H
CH
2OP
6x P
hosp
hogl
ycer
at6x
ATP
6x B
isph
osph
ogly
cera
t6x
AD
P
CO
O OH
H
CH
2OP
P
1. T
eilre
aktio
n: A
ktiv
ieru
ng d
er C
arbo
xylg
rupp
e
Cal
vin-
Zykl
us2.
Pha
se: R
eduk
tion
6x B
isph
osph
ogly
cera
t6x
(NA
DP
H +
H+ )
CO
O OH
H
CH
2OP
P
6x G
lyce
rinal
dehy
d-3-
Pho
spha
t6x
(Pi+
NA
DP
+ )
CH
O OH
H
CH
2OP
2. T
eilre
aktio
n: R
eduk
tion
der a
ktiv
ierte
n C
arbo
xylg
rupp
e
Cal
vin-
Zykl
us3.
Pha
se: R
egen
erat
ion
von
Rib
ulos
e-B
isph
osph
at
aus
Cam
pbel
l & R
eece
: „B
iolo
gy“ 6
thed
.
3x
3x6x
6x
6x
5x
1x
ATP
NAD
PH+
H+
ATP
ADP
NAD
P+
Cal
vin-
Zykl
us3.
Pha
se: R
egen
erat
ion
von
Rib
ulos
e-B
isph
osph
at
5x G
lyce
rinal
dehy
d-3-
Pho
spha
t3x
ATP
3x R
ibul
ose-
Bis
phos
phat
3x A
DP
Fig.
10-
UN
2
Reg
ener
atio
n of
CO
2ac
cept
or
1 G
3P (3
C)
Red
uctio
n
Car
bon
fixat
ion
3 C
O2
Cal
vin
Cyc
le
6 u
3C
5 u
3C
3 u
5C
The
Impo
rtan
ce o
f Pho
tosy
nthe
sis:
A R
evie
w
•Th
e en
ergy
ent
erin
g ch
loro
plas
ts a
s su
nlig
ht g
ets
stor
ed a
s ch
emic
al e
nerg
y in
org
anic
com
poun
ds
•S
ugar
mad
e in
the
chlo
ropl
asts
sup
plie
s ch
emic
al
ener
gy a
nd c
arbo
n sk
elet
ons
to s
ynth
esiz
e th
e or
gani
c m
olec
ules
of c
ells
•P
lant
s st
ore
exce
ss s
ugar
as
star
ch in
stru
ctur
es
such
as
root
s, tu
bers
, see
ds, a
nd fr
uits
•In
add
ition
to fo
od p
rodu
ctio
n, p
hoto
synt
hesi
s pr
oduc
es th
e O
2in
our
atm
osph
ere
Cop
yrig
ht ©
200
8 Pe
arso
n Ed
ucat
ion,
Inc.
, pub
lishi
ng a
s Pea
rson
Ben
jam
in C
umm
ings
Fig.
10-
21
Ligh
tR
eact
ions
:Ph
otos
yste
m II
Elec
tron
tran
spor
t cha
inPh
otos
yste
m I
Elec
tron
tran
spor
t cha
in
CO
2
NA
DP+
AD
P Pi
+
RuB
P3-
Phos
phog
lyce
rate
Cal
vin
Cyc
le
G3P
ATP
NA
DPH
Star
ch(s
tora
ge)
Sucr
ose
(exp
ort)
Chl
orop
last
Ligh
t
H2O O
2
Fig.
10-
UN
1
CO
2
NA
DP+
redu
ctas
e
Phot
osys
tem
II
H2O O
2
ATP
Pc
Cyt
ochr
ome
com
plex
Prim
ary
acce
ptor
Prim
ary
acce
ptor
Phot
osys
tem
I
NA
DP+
+ H
+
Fd
NA
DPH
O2
H2O
Pq
Fig.
10-
UN
2
Reg
ener
atio
n of
CO
2ac
cept
or
1 G
3P (3
C)
Red
uctio
n
Car
bon
fixat
ion
3 C
O2
Cal
vin
Cyc
le
6 u
3C
5 u
3C
3 u
5C
Fig.
10-
UN
3
pH 7
pH 4
pH 4
pH 8
ATP
Fig.
10-
UN
4
Fig.
10-
UN
5