lipid synthesis is a primary function of which organelle
Endomembrane system Most lipids are synthesized in yeast either in the endoplasmic reticulum, lipid particles, or the mitochondrion, with little or no lipid synthesis occurring in the plasma membrane or nuclear membrane.[12][13] Sphingolipid biosynthesis begins in the endoplasmic reticulum, but is completed in the Golgi apparatus.[14] The situation is similar in mammals, with the exception of the first few steps in ether lipid biosynthesis, which occur in peroxisomes.[15] The various membranes that enclose the other subcellular organelles must therefore be constructed by transfer of lipids from these sites of synthesis.[16] However, although it is clear that lipid transport is a central process in organelle biogenesis, the mechanisms by which lipids are transported through cells remain poorly understood.[17]
Lipid Triglycerides, stored in adipose tissue, are a major form of energy storage both in animals and plants. They are a major source of energy because carbohydrates are fully reduced structures. In comparison to glycogen which would contribute only half of the energy per its pure mass, carbohydrate carbons are all bounded to hydrogens unlike in carbohydrates.[66] The adipocyte, or fat cell, is designed for continuous synthesis and breakdown of triglycerides in animals, with breakdown controlled mainly by the activation of hormone-sensitive enzyme lipase.[67] The complete oxidation of fatty acids provides high caloric content, about 38 kJ/g (9 kcal/g), compared with 17 kJ/g (4 kcal/g) for the breakdown of carbohydrates and proteins. Migratory birds that must fly long distances without eating use stored energy of triglycerides to fuel their flights.[68]