Photosynthesis



  • In the Z scheme, when is electron transported uphill & when downhill? Please explain.
    0_1547278722767_IMG_20190112_130809933~2.jpg
    From PS II to PS I, is the transport uphill or downhill? I am confused in the underlined part (in above pic) as both uphill & downhill are mentioned. Please explain.
    0_1547278852483_IMG_20190112_131017207~2.jpg



  • @anag
    When PS2 acquires sufficient amount of light energy,it becomes excited & emits electrons
    *The electrons (with high energy) run down an an electron transport chain, consisting of a primary acceptor, plastoquinone, cytochrome complex & plastic Yanina to PS1 which transfers them to ferredoxin



  • @anag
    Whenever molecules gain or lose electrons energy is involved. The Z-scheme is an energy diagram for electron transfer in the "light reactions" of plant photosynthesis. It applies equally well to photosynthesis by algae and cyanobacteria. The vertical energy scale shows each molecule’s ability to transfer an electron to (i.e., to reduce) the next one from left to right. The ones at the top transfer electrons easily to the ones below them as it is a "downhill" reaction, energy-wise. However, for electron transfer from those at the bottom to those above them it is an "uphill" reaction and requires input of outside energy. The Z scheme shows the pathway of electron transfer from water to NADP+. Using this pathway, plants transform light energy into "electrical" energy (electron flow) and hence into chemical energy as reduced NADPH and ATP.



  • @sunitasaxena Total how many ATP is needed for uphill transport throughout the Z scheme?



  • @anag
    One ATP is produced during downhill of each turn
    According to my understanding,6 turns of cyclic and non-cyclic photophosphorylation is required to produce one molecule of glucose. Because 6 turns of non cyclic photophosphorylation will produce 12 N A D P H 2 and 6 ATP molecules. And cyclic photophosphorylation will produce 12 ATP molecules.


Log in to reply
 

Powered by dubbtr | @2019

Looks like your connection to dubbtr was lost, please wait while we try to reconnect.