Q7(b). Ferredoxin: structure and role in photosynthesis
Describe the structural features of ‘ferredoxin’ molecule. What is its role in photosynthesis?
Answer in brief
Small non-haem Fe–S proteins (Fe tetrahedral; cysteine S and bridging sulfide; [2Fe–2S], [4Fe–4S]); one-electron carriers at very negative potential. They take electrons from photosystem I and, through FNR, reduce NADP⁺ to NADPH.
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As written for the answer booklet: the diagram carries the working, the lines stay short. Read here only; it is not offered as a download.
Coversnon-haem ironcysteine thiolateinorganic sulfidephotosystem Iferredoxin
All parts of Question 7
- 7(a)(i) Metal carbonyls; how they are formed; tetrahedral Ni(CO)₄10 marks
- 7(a)(ii) Structure of Fe₂(CO)₉ and the 18-electron rule10 marks
- 7(b) Ferredoxin: structure and role in photosynthesis10 marks
- 7(c) Isomers of [CoCl₂(en)₂]⁺; is there a meso form?10 marks