Primary bile acids are which?

• A. Cholic and Chenodeoxycholic Acid
• B. Deoxycholic and Lithocholic Acids
• C. Ursodeoxycholic Acid and Chenodeoxycholic Acids
• D. Cholic Acid and Deoxycholic Acid

Answer: (A)

Primary bile acids are made in the liver from cholesterol and secreted into bile. In humans, the two main ones are cholic acid and chenodeoxycholic acid. These acids are then conjugated with glycine or taurine to form bile salts that help emulsify fats in digestion. In the gut, bacteria can modify them to produce secondary bile acids, such as deoxycholic acid and lithocholic acid. Ursodeoxycholic acid is a derivative of chenodeoxycholic acid and is viewed as a secondary bile acid. So, the two primary bile acids are cholic acid and chenodeoxycholic acid.