A series of compartmentalized, small tubes that collect or transport substances in bodily organs.
A small tube. There are several named tubules in the body: examples include convoluted tubules in the nephron of the kidney and the seminiferous tubules in the testes.
An extremely minute, tube-like structure found in the nephron of the kidney, responsible for extracting certain ions and molecules from the blood and transferring them into the fluid within the tubule.