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How do substrates from the TCA get out of the mitochondria to become fatty acids?

User Nejla
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Final answer:

Fatty acid synthesis occurs when acetyl-CoA from the TCA cycle in the mitochondria is transported out to the cytoplasm. This is facilitated by the formation of citrate or acetylcarnitine, which help move acetyl-CoA across the mitochondrial membrane.

Step-by-step explanation:

The substrates from the tricarboxylic acid (TCA) cycle, which occurs in the mitochondria, can become fatty acids through a process of transportation and conversion. Acetyl-CoA, a substrate in the TCA cycle, can exit the mitochondria to be used in fatty acid synthesis. When acetyl-CoA builds up in the mitochondria, it can join oxaloacetate to form citrate, which can cross the mitochondrial membrane. Citrate is then converted back into acetyl-CoA and oxaloacetate in the cytoplasm via citrate lyase. Another method of transport occurs when acetyl-CoA combines with carnitine to form acetylcarnitine for transport out of the mitochondria to the cytoplasm.

Lipogenesis, the chemical process of synthesizing fatty acids, happens in the cytoplasm and the endoplasmic reticulum, utilizing the acetyl-CoA that has been transported out of the mitochondria. The transport mechanisms involve citrate and acetylcarnitine, ensuring that the mitochondrial acetyl-CoA can enter the cellular pathways for fatty acid synthesis.

User Rohan Bagchi
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