Photosynthesis Flashcards
(23 cards)
Name 2 uses of ATP
- Provides energy for active transport/muscle contraction/protein synthesis
- Phosphorylation- Binds to enzymes or substrates (Lowers Ea, or makes molecule more reactive.
Why is atp so useful
It can:
Release energy in small amounts
Be broken down in one step
Make energy available rapidly
Phosphorylate
Make phosphorylated substances more reactive
Can be reformed
What is NADP
A molecule that acts as a hydrogen acceptor and becomes reduced NADP/NADPH
What does photosynthesis cinvert light energy into?
Chemical
What is the equation for photosynthesis?
6CO2 + 6H2O —> C6H12O6 + 6O2
What are the 2 stages by which photosynthesis occurs through
LDR
LIR
What are the products of light dependent reactions
ATP NADPH and O2
What is required for light dependent reactions to occur
Light and water
What is needed for light INDEPENDENT reactions to occur
ATP, NADPH and CO2
What is produced from LIR’s
Glucose and other organic compounds
What does photoionisation cause chlorphyll to do
Oxidise, releasing excited electron
Where do high energy electrons move once released from chlorophyll
Into the electron transport chain
What is the electron transport chain used for
Used to give energy to proton pump which creates an electrochemical gradient
Why is an electrochemical gradient needed
For protons to diffuse through ATP synthase (photophosphorylation) which provides energy to synthesise ATP
What can the products of photolysis be used for
Electrons can be used to replace those released by chlorophyll from photoionisation
H+ and associated electron can be used to reduce NADP
(O2 is a useful waste product)
What are the products of photlysis
4H+, 4e- and O2
How are protons pumped into the thylakoid space
using energy released from electrons
where does photolysis occur
in the thylakoid space
what are the three stages of the calvin cycle
Carbon fixation
Reduction
Regeneration
What happens in the carbon fixation stage
RuBP accepts CO2 in a reaction that is catalysed by rubisco, this forms 2 x GP molecules
What happens during the reduction phase?
GP is reduced into Triose Phosphate
Requires the oxidation of NADPH
Requires ATP
What happens to Triose phosphate in the calvin cycle
Converted into useful organic compounds
Used to regenerate RuBP
What happens in the regeneration stage
Triose Phosphate is used to regenerate RuBP using phosphate from ATP
