A 9-Dof wheelchair mounted robotic arm system (WMRA) has been developed to assist wheelchair-bound persons with upper limb motion limitations to perform activities of daily living (ADL) tasks. In this paper, we utilize mobile manipulation control to keep the end-effector stationary while moving the base and vice versa. This allows easier execution of a group of pre-set ADL tasks including opening and holding a spring loaded door passing through by locking the end-effector position and orientation. Redundancy resolution is achieved by optimizing the manipulability measure while the ADL task is being performed. Combined mobility and manipulation is expanded in this work to turn the USF WMRA into a task-oriented robotic system.