A lobule is a small, rounded section of an organ or tissue in the body. It is often used to describe parts of the liver, lungs, and mammary glands. Each lobule can function independently while still being part of a larger structure, allowing for efficient processing and organization of biological functions. In the liver, for example, lobules are the basic functional units that help in filtering blood and producing bile. Similarly, in the lungs, lobules contain clusters of alveoli, where gas exchange occurs. Understanding lobules is essential for studying the anatomy and physiology of various organs.