has part has part has_part elastic fiber smooth muscle tissue https://upload.wikimedia.org/wikipedia/commons/3/3b/Glatte_Muskelzellen.jpg GO uses visceral and smooth interchangeably. However visceral can also be used in the sense of the viscera. Many fly annotations to smooth muscle terms. If we want to be inclusive of insects have to have a general definition of tissue that includes cells. striated muscle tissue muscle tissue