Final answer:
The key substrate in lipogenesis is Acetyl CoA(a). It is crucial for creating fatty acids and other lipids, which serve as an efficient way to store energy in the body.
Step-by-step explanation:
The key substrate in lipogenesis is Acetyl CoA(a). During this process, when glucose levels are high, the body converts excess acetyl CoA into fatty acids, triglycerides, and other lipids. This process occurs primarily in the adipocytes and hepatocytes, where acetyl CoA, derived from glycolysis, initiates the creation of lipids. Lipogenesis involves adding two-carbon atoms from acetyl CoA repeatedly to grow the fatty acid chains to the required length, which consumes ATP. This mechanism provides an efficient way of storing energy, as triglycerides and lipids act as high-energy molecules and are held in adipose tissue until needed.