Photosynthesis Flashcards
What is photosynthesis
Photosynthesis converts light energy into chemical energy stored in carbohydrates (sugars) and other organic compounds
What drives photosynthesis?
Light energy from the sun drives the reaction
What are the fates of striking a leaf?
Absorbed, reflected, transmitted
Where is light absorbed?
Into the chloroplast
What do photosynthetic pigments do?
The photosynthetic pigments absorb light energy and convert it into chemical energy
What are carotenoids?
The carotenoids are accessory pigments that absorb other wavelengths of light. The carotenoids extend the range of wavelengths absorbed and pass this energy onto chlorophyll
What is the absorption spectrum?
The absorption spectrum shows the extent to which different colours of light are absorbed by a pigment.
What is the action spectrum?
The action spectrum shows the rate of photosynthesis carried out in different wavelengths of light
What is the first stage of photosynthesis called?
Light dependent stage
What happens when a pigment absorbs light energy?
an electron in the molecule becomes excited i.e. the electron’s energy level is raised to become a high-energy electron
What happens to a high energy electron?
transferred through the electron transport chain to bring about production of ATP by the enzyme ATP synthase
Where does the energy for photolysis come from?
Light energy
What happens in photolysis?
Water is split into oxygen which is evolved as a by-product of the reaction, and hydrogen
What happens to hydrogen after photolysis takes place?
hydrogen which is transferred to the coenzyme NADP and combined to produce NADPH
What products from the light reactions stage go onto the carbon fixation stage/Calvin cycle?
ATP and NADPH
