What is the difference between a ketone and a ketone body?

Answer

Hi Cara,

In chemistry, a ketone is a C=O in the middle somewhere in a chain (eg acetone: CH3-CO-CH3). In biology, ketone bodies are three molecules (including acetone) that are formed in our body (in our cells) based mainly on fatty acids as an alternative food source for glucose from our nerve cells (and brain) when there is a shortage of sugar in the diet and in the liver storage. The molecules known as ketone bodies are: acetoacetic acid, hydroxybutyric acid and acetone. In this, hydroxybutyric acid does not carry a ketone group, but this is a derivative (reduction product) of acetoacetic acid that does contain a ketone group. Acetone is also a derived molecule of acetoacetic acid, but the keto group is preserved, but the acid group is not (decarboxylation).

Sincerely

Myriam Meyers

KULeuven