All employees of the city shall be governed by civil service rules and regulations prescribed in or promulgated pursuant to this part and administered by a civil service board created under Section 45-8A-112.04. Present employees shall remain in their respective employments during good behavior; but nothing in this part shall be construed to prevent or preclude the removal of an employee for cause as provided for in this part; and the employees, except for appointment, shall be subject fully to this part.