AP Bio Chapter 9 Photosynthesis Part 2 Flashcards
Light+chlorophyll =
Electrons
What produced in light reactions are used to incorporate what in the Calvin cycle
The ATP and NADH are used to incorporate CO2 into a 3 carbon sugar
What happens when photons of light interact with chlorophyll
Electrons in magnesium atom get excited
What happens when chlorophyll gets excited by the right frequency of wave length, and what does this do. What percent does this occur with with all sunlight
Electron can be kicked off. Creates energy. Cone version of light energy —> chemical energy
~1% that strikes the earth
What will isolated chlorophyll do when exposed to light
Fluorescence , as the excited electrons return to the ground state
Whee are photosystems located
The thylakoid membranes
What is the path of the electron moved
Goes through ETC, powers proton pumps, therefore H+ are pumped through ATP synthase to make ATP
Photosystems
Complexes of protein and pigment molecules that are embedded on the thylakoid membrane
What do photosystems do involving photons
Direct incoming photons into the “reaction center” where chlorophyll molecules produce excited electrons which are transferred to an ETC.
What are the two types of photosystems (light independent reactions)
Photosystem 2 and photosystems 1
Photosystem 2
Central chlorophyll works best at a light wavelength of 680nm. (P680) found at the “start of ETC”
Photosystem 1
Central chlorophyll works best at a light wavelength of 700nm (P700) found at the “end of ETC”
Why are new electrons needed in these photosystems
Because chlorophyll is not going to have electrons return to it
What is the process of electrons in these photosystems
Electrons in p2 wind up replacing electrons in p1, then used to form NAD+ to produce NADPH.
What does the electrons do while in its path in photosystems
Powers pumps
