Download Photo Notes - Intro

Photosynthesis - continued
- 6CO2 + 12H2O
Light, Pigments
Enzymes
C6H12O6 + 6O2 + 6H2O
- Takes place in two major stages:
1. Light dependent stage
 Requires direct involvement of light to occur.
 Light is captured by pigments located in the
thylakoids which are found inside the chloroplast.
 Energy from light is used to create ATP and
NADPH (nicotinamide adenine dinucleotide
phosphate). Both are high energy compounds.
 A process called the electron transport chain, located
in thylakoid membrane, occurs in this stage and is
responsible for creating the ATP and NADPH.
 H20 is used in this stage and O2 (waste) is made.
2. Light independent stage
 Series of chemical reactions that produce glucose
A
Rxn
B
Rxn
C
Rxn
D
Rxn
E
 Sometimes is called the “dark” stage but this is
misleading. This stage can occur in either dark or
light, does not need direct sunlight.
 Uses the products of the light dependent stage, ATP
and NADPH.
 Involves direct input of CO2
 Produces glucose
 Occurs in a cycle, called the Calvin Cycle, due to the
series of chemical reactions starting and ending with
the same molecule. (draw picture)
 All steps are enzyme driven
 Calvin Cycle takes place in a liquid filled area of the
chloroplasts called the stoma
 It takes 6 “turns” of the cycle to create one glucose
 The 6 carbons for the glucose come from the 6CO2
and is called carbon-fixation due to carbons being
taken from an inorganic compound (CO2) and being
“fixed” into an organic compound (C6H12 O6)
 Occurs in a cycle, called the Calvin Cycle, due to the
series of chemical reactions starting and ending
with the same molecule.
A
Rxn
Rxn
B
Rxn
Rxn
C
Rxn
Rxn
D
Rxn
Rxn
A
 All steps are enzyme driven
 Calvin cycle takes place in a liquid filled area of the
chloroplast called the stroma
 It takes six “turns” of the cycle to create one glucose
 The six carbons for the glucose come from six CO2
and is called carbon-fixation due to carbons being
taken from an inorganic compound (CO2) and being
“fixed” into an organic compound (C6H12O6).
CO2
6 Carbon
Sugar
ATP
RuBP
(5 Carbon Sugar)
ADP
Calvin Cycle
NADPH
NADP
C
6 turns
C6H12O6 (glucose)
Photosynthesis - continued
Chloroplast
outer membrane
inner membrane
granum
stroma
thylakoid