Capillary can refer to multiple concepts, so here are three definitions for different contexts:
- Capillary (anatomy): In anatomy, a capillary refers to the smallest blood vessels in the body’s circulatory system. These microvessels connect arteries and veins, facilitating the exchange of oxygen, nutrients, and waste products between the bloodstream and surrounding tissues. Capillaries have thin walls, allowing for efficient diffusion of substances.
- Capillary (physics): In physics, a capillary is a small, narrow tube or channel through which fluids can flow. Capillary action, also known as capillarity, is the phenomenon where a liquid can rise or be drawn into a narrow space against the force of gravity. This effect is due to adhesive and cohesive forces between the liquid and the walls of the capillary.
- Capillary (chemistry): In chemistry, a capillary refers to a thin, narrow tube used for various purposes. For instance, capillary tubes are commonly used in laboratory experiments to measure small amounts of liquid or for separating substances based on their different rates of migration along the capillary. Capillary electrophoresis is a technique that employs capillary tubes to separate charged particles or molecules based on their electrophoretic mobility.