Zusammenfassung der Ressource
(AQA A2) Biology - Energy Transfer:
Photosynthesis
- Chloroplast
- Have Disc Like Structures
called Thylakoids.
- Stacks of Thylakoids are called
Grana
- Have a Fluid substance within; called
Stroma
- Adjacent Granas are linked by Lamella
- Keywords
- Oxidation is gain of electrons
- Reduction is lost of
electrons.
- Photoionisation is where a chlorophyll becomes positively
charged as it loses two electrons when absorbing light.
- Photolysis is the breakdown of water to
release proton, electrons and oxygen.
- Light Independent
Cycle
- Occurs in the Stroma
- Known as the
Calvin Cycle
- (STEP !) Carbon Dioxide reacts with RuBP
(Ribulose Bisphosphate)
- Produces 2 GP (Glycerate 3-Phosphate)
- Catalysed by the
Enzyme Rubisco
(Ribulose
Bisphosphate
Carboxylase)
- (STEP 2) GP is reduced to Triose Phosphate
- Requires reduced NADP (from
light-dependent Reaction) and ATP
- SOME Triose Phosphate are CONVERTED into
useful Organic Substances
- MOST Triose Phosphate is CONVERTED into Glucose.
- SOME Triose Phosphate is USED to regenerate RuBP
- Can be Investigated using Radioactively
Labelled CO2
- Light Dependent Reaction
- Occurs in Thylakoid
Membrane
- (STEP 1) Chlorophyll absorb light
energy, and electrons move up energy
levels, leaving the Chlorophyll.
- (STEP 2) Electrons are taken up by Electron Carriers, and
transferred along the ETC (Electron Transfer Chain)
- The electrons, as they go down lower energy levels, release energy; which is used for ATP
- Photolysis takes place.
- Proton and electrons produced,
is used to reduce NADP into
reduced NADP
- Rate of Photosynthesis
- Factors
- Light Intensity
- Carbon Dioxide Concentration
- Temperature
- Availability of Water in Soil
- The Factor that limiting Photosynthesis is the Limiting Factor