Photosynthesis: Outline Flashcards
what is the overall equation for photosynthesis?
6CO₂ + 6H₂O (+ light) → C₆H₁₂O₆ + 6O₂
what is some of the light energy conserved in the form of?
chemical bonds
what are the 3 main stages of photosynthesis?
- capturing of the light energy
- the Light Dependent Reaction (LDR)
- the Light Independent Reaction (LIR)
how is the light energy captured?
by chloroplast pigments (such as chlorophyll)
briefly summarise what happens during the LDR
- some absorbed light energy is conserved in chemical bonds
- electron flow is created by the effect of light on chlorophyll
- this causes water to split (photolysis) into protons (H⁺), electrons and oxygen
- the products are NADP, ATP and oxygen
briefly summarise what happens during the LIR
- protons (H⁺) are used to produce sugars and other organic molecules
what are the 2 purposes of the light energy during LDR?
- to add an inorganic phosphate (Pᵢ) to ADP, to form ATP
2. (photolysis) light causes water to split into protons (H⁺) and hydroxide ions (OH⁻)
what is oxidation?
the process when a substance gains oxygen or loses hydrogen, and energy is given out
what is a substance said to be when it gains oxygen or loses hydrogen?
oxidised
what is reduction?
the process when a substance loses oxygen or gains hydrogen, and energy is taken in
what is a substance said to be when it loses oxygen or gains hydrogen?
reduced
when a substance is oxidised what happens to its electrons?
electrons are lost
when a substance is reduced what happens to its electrons?
electrons are gained
oxidation and reduction always take place together, what is this type of reaction called?
redox reaction
in eukaryotic plants, which organelle does photosynthesis take place in?
chloroplasts
