Question

Fatty acid synthesis can be divided into 3 stages: Stage 1. Export of acetyl CoA from the mitochondria, Stage 2: Synthesis of malonyl CoA, and Stage 3 _______________
a) Import of acetyl CoA into mitochondria
b) Export of acetyl CoA from the mitochondria
c) Import of acyl CoA into cells from extracellular sources
d) Export of malonyl CoA from the mitochondria
e) Synthesis of palmitic acid.

Answer 1

Answer:

The third stage in the synthesis of fatty acids is the synthesis of palmitic acid (letter e)

Explanation:

The synthesis of fatty acids takes place in the cytoplasm of the cell. The first step is the transport of acetyl-CoA to the cytoplasm. This came in the form of citrate usually from the pyruvate generated in the glycolysis from the mitochondria. The citrate is enzymatically transformed into acetyl-CoA.

Once the acetyl-CoA is in the cytoplasm, this is transformed into malonyl-CoA. This molecule will be the donor of two carbons in the synthesis of fatty acids.

In the final step takes place a cyclic process of reactions (condensation, reduction, hydration and second reduction) to synthesize the palmitic acid ( 16 carbons) by the fatty acid synthase.