All employees to whom this article applies shall be governed by merit system rules and regulations prescribed in or promulgated pursuant to this article, administered by the merit system board, the creation of which is provided for in Section 45-18-120.04. Present such employees shall remain in their respective employments during good behavior; but nothing herein shall be construed to prevent or preclude the removal of such an employee for cause in the manner hereinafter provided; and such employees shall be subject fully to this article.