All boards and commissions which under this chapter are a part of or are attached to the Agency shall be advisory only, except as hereinafter provided, and the powers and duties of the boards and commissions, including administrative, policy making, and regulatory functions, shall vest in and be exercised by the Secretary of the Agency. Boards of registration attached to this Agency shall retain and exercise all existing authority with respect to licensing of the persons registered or applying for registration. (Added 1969, No. 271 (Adj. Sess.), § 3, eff. Jan. 10, 1971.)