Final answer:
The starting point for ketone body synthesis is acetyl CoA, from which the liver synthesizes HMG CoA, followed by the production of B-hydroxybutyrate, the primary ketone body. Ketone bodies serve as energy sources when glucose is limited and are also important for diagnosing certain metabolic conditions.
Step-by-step explanation:
Ketone Body Synthesis Starting Point
The starting point for ketone body synthesis is acetyl CoA. This synthesis occurs primarily in the mitochondria of liver cells, where excess acetyl CoA is first converted into hydroxymethylglutaryl CoA (HMG CoA). HMG CoA acts as an intermediate and is then converted into the primary ketone body found in the blood, B-hydroxybutyrate. Ketone bodies can be utilized by organs, such as the brain, as an alternative source of energy during times when glucose supply is low.
Ketone bodies include acetoacetic acid, beta-hydroxybutyric acid, and acetone. Generated from acetyl CoA, these ketone bodies originate from the metabolism of glucose, fatty acids, and amino acids. During prolonged starvation or poorly controlled diabetes, the concentration of ketone bodies increases, leading to conditions like ketoacidosis.