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Where in plants photo occur?
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Stomata
- Pores in the leaf surface that allow for gas exchange
- Through the stomata, carbon dioxied enters the plant and oxygen and water vapor exit the plant
- To conserve water under dry conditions, the stomata remain closed to reduce the loss of water vapor
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Thylokoids
- Have double membrane. Stacked into Grana
- Where photosyn. starts with absorption of sunlight. Thylokoid membranes contain a pigment -chlorophyll a and other accessory pigments aid it in a absorbing sunlight
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Two stages of photosynthesis
- 1st stage: (light reactionsThe power of sunlight will 1.strip electrons off water and then 2. boost these electrons to a higher energy level. When boosted, the electrons are passed along through a series of the electron carriers. All of this takes place in thylokoid membranes. This stage ends when the original, energized electrons get attached to a mobile electron carrier - NADP+ that transport them to the second set of reactions.
- 2nd stage:(Celvin cycle) attachment of electrons to CO2 and sugar the carbon fixation, occur in stroma
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photosystem
- in thylokoid membranes, molecules collect solar energy and converts to chemical energy.
- Components are: chloropyll a -serve as antennae that absorb energy from sun and pass it on to the reaction center.
- At the center of photosystem is a reaction center(have special chlorophil pigments) that first receive solar energy from photosys, pigment sna transofrm this solar energy into chem. This molecules are the "primary electron acceptors)
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