The governor may prescribe all general administrative rules for the conduct of the affairs of the administrative departments, not inconsistent with law which he may deem necessary or expedient.  The head of the department may prescribe all administrative rules with the approval of the board of the department which he may deem necessary or expedient for the proper conduct of the work of the department and for making effective the provisions of law and which are not inconsistent with any provisions of law or with any general rules prescribed by the governor.