Light Dependant and Independant (Dark) Reactions Flashcards
Light _________ Reactions
-The clustered arrangement of pigments in Thylakoids
-Contains two Photosystems
-All absorbed sunlight energy is passed to a reaction centre
Light Dependant Reactions
Each PS (Photosystem) has about __ Chlorophyll molecules and a few carotenoids and a molecule that accepts electrons.
12
In Light Dependant Reactions, all absorbed sunlight energy is passed to a specialized electron-accepting Chlorophyll a molecule called the..
Reaction Centre
What happens when energy (e-) is passed from the other pigments to the reaction centre?
it becomes “excited” / the electrons have been raised to a higher energy level
What happens when electron (e-) is passed from the reaction centre to the electron accepting molecule?
it becomes reduced (gains an electron) and has a higher energy level
the splitting of water
Photolysis
What does Photolysis produce?
electrons, oxygen, and hydrogen ions (H+)
How are electrons produced for Light Dependent Reactions?
Electrons are produced by the splitting of water (Photolysis)
The energized electron is passed through a series of electron carrying molecules called..
Electron Transport Chain (ETC)
As the electron is passed to electron acceptors, it falls to a _____ energy state.
Lower
The released energy pushes __ ____ from the Stroma into the inner Thylakoid space.
H+ Ions
The pushed H+ from the released energy creates a..
Concentration Gradient
Provides a “push” to regenerate ATP from ADP + P
Concentration Gradient
As H+ move down the concentration gradient, it drives the reaction that generates ___.
ATP
Creating ATP using H+ concentration gradient
Chemiosmosis
Using light to make ATP (adding P to ADP)
Photophosphorylation
The electron from PSI is used to reduce NADP+ into..
NADPH
The reducing power (NADPH) will be used in..
Light Independent Reactions
An electron from _____ replaced the electron that was lost from PSII
water
The oxygen from the water molecule is converted to molecular ______.
Oxygen (O2)
Light Dependant Reaction happens in the..
Thylakoids
Reaction Center is full of..
Chlorophyll!!!!!!!
Light ___________ Reactions
-Series of reactions that “fixes” atmospheric CO2 into Glucose.
-If sufficient NADPH and ATP in the stroma, the energy of these molecules can be used to synthesize Glucose in the presence or absence of Light
Independent
five-carbon compounds
RuBP
Dark Reaction takes place in the..
Stroma
6 carbon chain
Carbon Fixation
Three-Carbon Chains with low energy
PGA
Three Carbon Chain with high energy
PGAL
Energy released during ETC forces __ across the thylakoid membrane and create a concentration gradient.
H+
Energy from the concentration gradient is used to generate ATP from ADP and P by means of..
Chemiosmosis
Series of reactions that “fixes” (adds) atmospheric CO2 into Glucose
Light Independent Reaction
If sufficient _____ and ___ in the Stroma, the energy of these molecules can be used to synthesize glucose in the presence or absence of light
NADPH and ATP
What are the steps of Dark Reaction?
- Carbon Fixation
- Reduction
- Replacing RuBP
What are the steps of light reaction?
- Photolysis and PSII
- Electron Transport Chain (ETC)
- PSI
- Reducing Power
What is carbon fixation?
When C atom from CO2 binds to a pre-existing 5 carbon molecule RuBP
New 6 Carbon from Carbon Fixation is ________ and quickly breaks down into 2 x 3C PGA molecules
Unstable
Reduction = ??
Charge up
The new 3 carbon molecules are in a ___ energy state
Low
The new PGA molecules are activated by ATP then Reduced by..
NADPH
How many PGAL leave the cycle to make Glucose?
One!!!
The remaining _ PGAL stays in the cycle
Five!!!
ATP produced from the light dependant reactions breaks and reforms the 3 carbon PGAL into 5 Carbon..
RuBP
What is the enzyme that fixes carbon?
Rubisco
