Photosynthesis Flashcards
What is the balanced equation for photosynthesis?
6H2O + 6CO2 —> C6H12O6 + 6O2
What is photosynthesis?
A series of enzyme catalysed reactions that synthesise organic molecules like glucose. Other take olace in the chloroplast
What is oxidation?
Loss of electrons, gain of oxygen
What is reduction?
Gain of electrons, loss of oxygen
What factors can increase photosynthesis due to its enzymes?
Increased temperature
Increased KE
More enzyme substrate complexes being formed
How are thylakoids beneficial for photosynthesis?
The light dependent reaction occurs in thylakoids, as it contains electron transport proteins and chlorophyll to absorb light energy
Why are grana useful in photosynthesis?
They increase the surface area so can absorb more light energy for the light dependent reaction
What is the role of the stroma in photosynthesis?
It contains enzymes used for the light dependent reactions
What is the role of starch grains?
They store excess carbohydrtaes made in photosynthesis
Where does the light dependent reaction take place?
In the thylakoid
Explain what happens during the light dependent reaction
- chlorophyll absorb light energy, a pair of electrons gain energy and become excited, so leave the chlorophyll. This reduces the chlorophyll. This is PHOTIONISATION.
- PHOTOLYSIS occurs in the stroma, where water is split into hydrogen ions, electrons and oxygen.
- the pair of electrons pass through electron carrier proteins and undergo a series of redox reactions. This releases energy that is used to pump the hydrogen ions through the thylakoid membrane to create a conc. gradient between the stroma and thylakoid lumen
- the hydrogen ions then travel from the lumen ro the stroma through ATP synthase down the conc. gradient. This causes PHOSPHORYLATION (ADP + Pi —> ATP)
- the pair of electrons and hydrogen ions are added to NADP to make reduced NADP.
