Final answer:
The liver is divided into a larger right lobe and a smaller left lobe, each composed of functional units known as lobules. These lobules are further organized into segments, which are important for the liver's vascular supply and organization.
Step-by-step explanation:
The four lobes of the liver are divided into lobules and segments. The liver itself is composed of a larger right lobe and a smaller left lobe, which some anatomists also consider containing an inferior quadrate lobe and a posterior caudate lobe, though these are not typically referred to as separate lobes but rather areas within the right lobe. Each lobe is made up of many lobules, which are the functional units of the liver. Each lobule consists of liver cells known as hepatocytes. These lobules are grouped into segments based on the vascular supply of blood to the liver. Understanding the structure and segmentation of the liver is crucial for surgical planning and diagnosing liver diseases.