photosynthesis
i. State the meaning of photosynthesis
light energy
coz 1- H2O carb t 02
by which coat H2O are converted to in the presence of
the process sugar
light energy and chlorophyll .
Oz is a waste product .
STAGES OF PHOTOSYNTHESIS
1. light dependent reaction ( LDR)
.
cyclic phosphorylation
.
cyclic phosphorylation
non -
.
photolysis
2. light independent reaction : Calvin 's cycle
PHOTOSYNTHETIC PIGMENTS tails made UP Of Hilo + head is made up of N,
Mg
#
.
1- Primary pigments :
alpha chlorophy,
- eh ,oropny
2. accessory 11 Beta chlorophyll Xanthrophilsicaratonoids , chlorophyll]
.
:
'
y
photosystem
•
•
-
-
-
.
.
: : :
:
-
thylakoid stroma
i i
-
- .
chloroplast
-
, PHOTOSYSTEM
-
these are light harvesting clusters made up of photosynthetic pigment molecules
.
primary pigment is made up of chlorophyla .
Accessory pigments consist of all other
molecule
-
photo activation : it is emission of high
-
energy electrons from chloro phyla
molecule when light energy falls on it .
.
accessory pigments are present around the primary pigment in the form of a
cone They help to collect and direct light energy towards the primary pigment
.
and they avoid loss of light energy
TYPES OF PHOTOSYSTEM's
I. photosystem I or 17700
photoactivation occurs at wavelength of light energy
700hm
-
Max -
II. Photosystem I Or 13680 Both PI and PI are present in a thylakoid
.
.
Kitt DEPENDENT REACTION
location : thylakoid
•
I cyclic phosphorylation
-
ADP 1- Pi ATP presence of light
Describe cyclic PPR .
-
Only PIP 700 is involved
•
light energy falls on the primary pigment photoactivation center of PI
high energy electrons are emitted from chlorophyll , a molecule
.
•
. electrons pass through ETC located in thylakoid membrane .
.
che miosmosis occurs and ATP is made .
.
electrons fall back into PI therefore . . . .
cyclic PPR
.
product of cyclic PPR ATP only
compare tabulate state differences between oxphos and cyclic PPR .
4
\ non -
cyclic phosphorylation .
both PI and PI are involved
i. Describe events of non -
cyclic PPR . 6 marks
PI involved
30th PI and are
.
photoactivation occurs , electrons are emitted from both photosystems
membrane, release energy which is used for chemiosmosis
.
electrons pass through ETC of thylakoid
-
ATP is made
. I do not fall back into their original system that is why it is called non -
cyclic PPR .
replaced by e- from PI
-
e- lost from PI are
-
e- lost from PI are replaced by é mole photolysis of water
in
.
photolysis of water occurs inside thylakoid space by an enzyme
i. State the meaning of photosynthesis
light energy
coz 1- H2O carb t 02
by which coat H2O are converted to in the presence of
the process sugar
light energy and chlorophyll .
Oz is a waste product .
STAGES OF PHOTOSYNTHESIS
1. light dependent reaction ( LDR)
.
cyclic phosphorylation
.
cyclic phosphorylation
non -
.
photolysis
2. light independent reaction : Calvin 's cycle
PHOTOSYNTHETIC PIGMENTS tails made UP Of Hilo + head is made up of N,
Mg
#
.
1- Primary pigments :
alpha chlorophy,
- eh ,oropny
2. accessory 11 Beta chlorophyll Xanthrophilsicaratonoids , chlorophyll]
.
:
'
y
photosystem
•
•
-
-
-
.
.
: : :
:
-
thylakoid stroma
i i
-
- .
chloroplast
-
, PHOTOSYSTEM
-
these are light harvesting clusters made up of photosynthetic pigment molecules
.
primary pigment is made up of chlorophyla .
Accessory pigments consist of all other
molecule
-
photo activation : it is emission of high
-
energy electrons from chloro phyla
molecule when light energy falls on it .
.
accessory pigments are present around the primary pigment in the form of a
cone They help to collect and direct light energy towards the primary pigment
.
and they avoid loss of light energy
TYPES OF PHOTOSYSTEM's
I. photosystem I or 17700
photoactivation occurs at wavelength of light energy
700hm
-
Max -
II. Photosystem I Or 13680 Both PI and PI are present in a thylakoid
.
.
Kitt DEPENDENT REACTION
location : thylakoid
•
I cyclic phosphorylation
-
ADP 1- Pi ATP presence of light
Describe cyclic PPR .
-
Only PIP 700 is involved
•
light energy falls on the primary pigment photoactivation center of PI
high energy electrons are emitted from chlorophyll , a molecule
.
•
. electrons pass through ETC located in thylakoid membrane .
.
che miosmosis occurs and ATP is made .
.
electrons fall back into PI therefore . . . .
cyclic PPR
.
product of cyclic PPR ATP only
compare tabulate state differences between oxphos and cyclic PPR .
4
\ non -
cyclic phosphorylation .
both PI and PI are involved
i. Describe events of non -
cyclic PPR . 6 marks
PI involved
30th PI and are
.
photoactivation occurs , electrons are emitted from both photosystems
membrane, release energy which is used for chemiosmosis
.
electrons pass through ETC of thylakoid
-
ATP is made
. I do not fall back into their original system that is why it is called non -
cyclic PPR .
replaced by e- from PI
-
e- lost from PI are
-
e- lost from PI are replaced by é mole photolysis of water
in
.
photolysis of water occurs inside thylakoid space by an enzyme
