Tissue

In biology, tissue is a cellular organizational level intermediate between cells and a complete organ. A tissue is an ensemble of similar cells from the same origin that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues.

The study of tissue is known as histology or, in connection with disease, histopathology. Modern tools allow tissues to be examined in health and disease, enabling considerable refinement of medical diagnosis and prognosis.