Notwithstanding Sections 24300 and 24304, the board of supervisors of any county may organize, pursuant to ordinance or charter, the delivery of health and human services for which county government is responsible under state law into departments that provide human assistance, human services, and medical systems. Any county board of supervisors which elects to so organize the delivery of health and human services may consolidate, integrate, and separate duties and functions of county offices, and organizational units within departments, to the extent deemed necessary by the board of supervisors, consistent with the provisions of this division.