But ultimately, this acetylco enzyme A molecule is found in the matrix of the mitochondria. And that poses a problem, because fatty acid synthesis takes place in the cytoplasm of the cell. But these acetylco enzyme A molecules are located in the matrix of the mitochondria. So we have to be able to move these acetylco enzyme A molecules from the matrix into the cytoplasm cell to actually initiate the process of fatty acid synthesis. Now, there's a problem with moving acetyl coenzyme A molecules across the membrane of the mitochondria. And the problem is it's water soluble.