Liver Anatomy and Functions

Liver Structure and Function

• The liver is divided into lobes, segments, and lobules by a capsule that sends extensions towards the inside of the liver around the vessels.
• The smallest functional unit of the liver is called the lobulus hepatis.
• Each lobule has a vena centralis, which unites to form vena hepatica and eventually opens into the inferior vena cava.

Functions of the Liver

• The liver is both an exocrine and an endocrine gland.
• It stores vitamins A, B, and heparin produced by mast cells.
• It participates in lipid production and releases urea by separating nitrogen from amino acids.
• It removes harmful substances, bilirubin, and drugs from the body.

Gallbladder Structure and Function

• The gallbladder is located in the fossa vesicae biliaris, just to the right of the lobus quadratus on the visceral surface of the liver.
• It is pear-shaped and can store an average of 50 ml of bile.
• It provides the storage and concentration of bile secreted from the liver.

Liver Ligaments and Relationship with Peritoneum

• Most of the liver is covered by the peritoneum, except for the area nuda, fossa vesicae biliaris, sulcus venae cavae, fissura ligamenti teretis, fissura ligamenti venosi, and porta hepatis.
• The liver is attached to the anterior abdominal wall and diaphragmatic surface by ligaments.
• Lig.falciforme hepatis separates the two lobes from each other.

Liver Faces and Edges

• The liver has two faces: facies diaphragmatica and facies visceralis.
• The facies diaphragmatica is large and mostly covered with peritoneum, except for the area nuda.
• The facies visceralis faces the abdominal organs and has a middle arch of the 'H' shape.
• The edge formed on the posterior side is called the margo posterior, and the edge formed on the anterior side is called the margo inferior.