Question 18

Outline the role of the liver in the metabolism of fat (1/3 of marks), carbohydrate (1/3 of marks) and proteins (1/3 of marks).

[Click here to toggle visibility of the answers]

College Answer

Most candidates seemed not to have thought about this before and so collated information 
from answers about insulin and glucagon, and starvation. Many added information about 
absorption and digestion which was not required. 
Metabolic functions of the liver form part of the “standard list” of functions of the liver yet few 
details could be provided beyond that. It was expected answers would detail the central role 
of the liver as a “glucostat” and its role in glucose utilization. It has two main roles in lipid 
metabolism, the synthesis of fatty acids and the partial oxidation of fatty acids to ketone 
bodies. The liver also plays a central role in protein catabolism and anabolism. It plays a 
major role in the breakdown of amino acids gluconeogenesis and protein synthesis. The liver 
also releases amino acids into the blood for utilization by peripheral tissues.