Which term describes groups of similar cells performing a specific task?

The term that describes groups of similar cells performing a specific task is "tissues." Tissues are composed of collections of cells that share a common structure and function, working collaboratively to carry out particular physiological roles in the body. This organization allows for specialized functions that contribute to the overall health and operation of organs and systems.

In the context of biological organization, tissues are one of the basic building blocks that, when grouped together, form organs (such as the heart or lungs), which serve broader functions. Tissues classify into types such as epithelial, connective, muscle, and nervous tissue, each with distinct roles in maintaining body processes.

While cells are the basic unit of life and can function individually, it is the cooperative arrangement of similar cells into tissues that enhances efficient function. Organs refer to structures made up of two or more types of tissues working together, while systems are collections of related organs that perform a set of functions. Thus, "tissues" specifically highlights the group of similar cells working together towards a common task.