In heme synthesis in mammalian cells:
Uroporphyrin III is the immediate precursor of coproporphyrin III
d -aminolevulinic acid is formed by the condensation of succinyl CoA and valine
Ferric iron is inserted into protoporphyrin IX prior to attachment to the globin molecule
- Porphobilinogen is formed by the condensation of two d-aminolevulinic acids
A, B and C
A and C
B and D
- D only
All of the above
- Neither compound is on the pathway of heme synthesis.
- Succinyl CoA condenses with glycine, not valine.
- It is iron (II), or ferrous iron, that is inserted.
- Correct. This is a dehydration reaction.
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