After approval of a merger by the board and any approval by the members (Section 5034) required by Section 8012, the surviving corporation shall file a copy of the agreement of merger with an officers’ certificate of each constituent corporation attached stating the total number of memberships of each class entitled to vote on the merger, identifying any other person or persons whose approval is required, and that the principal terms of the agreement in the form attached were duly approved by the required vote of the members and, if applicable, any other person or persons. The merger and any amendment of the articles of the surviving corporation contained in the merger agreement shall thereupon be effective (subject to subdivision (c) of Section 5008 and subject to the provisions of Section 8018) and the several parties thereto shall be one corporation. The Secretary of State may certify a copy of the merger agreement separate from the officers’ certificates attached thereto.