A collection of cells and extracellular materials that perform a discrete function is known as a(n)

The answer to the question is "tissue."

Tissue is an organized group of cells that work together to perform specific functions within an organism. Different types of tissues serve various roles in the body: for instance, muscle tissue is responsible for movement, nervous tissue is involved in transmitting signals, connective tissue supports and binds other tissues together, and epithelial tissue forms protective layers. These specialized groups of cells, along with extracellular materials such as fibers and ground substances, are crucial for the overall function and health of an organism. Each type of tissue has a unique structure and composition that enables it to carry out its specific function effectively, highlighting the complexity and efficiency of biological systems.