In order to avail itself of the powers conferred by this article, the municipal governing body shall appoint a commission to be known as the zoning commission to recommend the boundaries of the various original districts and to recommend appropriate regulations to be enforced therein. The commission shall make a preliminary report and hold public hearings thereon before submitting its final report. The governing body shall not hold its public hearings or take action until it has received the final report of the commission. Where a municipal planning commission already exists, it shall be appointed as the zoning commission.