Whenever conditions warrant, the Labor Commissioner or the chairman of the board shall request the Governor to appoint, and the governor shall have authority to appoint, one or more alternate members to the Board of Mediation and Arbitration in such numbers as may be necessary, in order that said board may render efficient service to employers and their employees whenever grievances or disputes arise. An alternate member may be so appointed for a period of up to one year or until a replacement is appointed. Alternate members so appointed shall have power to complete any matter pending at the expiration of the terms for which they were appointed. Alternate labor members shall be members of a bona fide national or independent labor organization. Alternate members of the Board of Mediation and Arbitration shall serve at any time when so delegated by the board and while so serving shall have all the powers of members of the board. Whenever an alternate member serves in place of a member of the board, he shall represent the same interest as the member in whose place he serves. Said board may, at its option, require alternate members to sit with it in the fulfillment of any function of the board.