We consider the nematiclike system of polymer liquid crystal (PLC) macromolecules represented by the Flory semiflexible chain model. Segments of the flexible (F) spacers are shorter than the LC hard-rod sequences. We investigate effects of imposition of external deformations. The behavior of LC sequences is largely governed by orienting interactions while for F spacers the short-range interactions determined by the chemical structure are the most important. The stress-strain relation is obtained in addition to the orientation-deformation relations. Orientational order phase transitions caused by the external deformations of the system are recognized and described. (C) 2004 American Institute of Physics.