development of differentiated myoblasts and satellite cells : -- primitive , undifferentiated tumor cells : small round cells with scanty cytoplasm containing few thin filaments ( 4 to 6 nm ) and intermediate-type filaments ( 10 nm ) , -- round or slightly spindle-shaped myoblast-like tumor cells : cells with moderate cytoplasm exhibiting irregularly arranged thin and intermediate-type filaments and only some thick filaments ( 15 nm ) , -- myotube-like cells : long extended cells ( strap shaped cells ) revealing thin and thick filaments , z-line material and different stages of myofibrillar organization , -- well-differentiated myoblasts : long extended cells showing typical cross-striations which correspond to well-formed sarcomeres with i-bands ( z-lines with extending thin filaments ) and a-bands , which are subdivided into h- and m-bands , -- satellite cells of typical ultrastructure associated with differentiated myoblasts by a common basement membrane present in one case .
C0007589
differentiated
C0007634
cells