The county commission may, by resolution or ordinance, create a county planning commission for the purpose of enforcing this chapter. The county commission shall appoint not less than five nor more than 11 members to the commission. The probate judge, chairman, or similar presiding officer of the county governing body shall be an ex officio member of said commission and shall vote only in case of a tie vote at a meeting wherein the entire membership is present and has voted. Members of the county commission may serve as members of the planning commission notwithstanding the provisions of Section 11-3-2, or any other provisions limiting the offices such governing officials may hold. The term of the ex officio member shall correspond to his official tenure. The terms of each appointive member shall be four years; provided, that, in the initial appointments to the commission, a majority, but not exceeding three fifths of the total membership of the commission, shall be appointed for two years and the remaining members for four years; and provided further, that any members of the county commission appointed to the planning commission for a term exceeding their official tenure as a member of the county commission shall, notwithstanding, continue to be a member of the said commission until the expiration of their appointment as such unless otherwise removed as subsequently provided in this section. Any vacancy in the membership of the planning commission shall be filled for the unexpired term in the same manner as the original appointment. Any appointed member of the commission shall be subject to removal by the county commission for cause after written notice. All members of the county planning commission shall serve as such without compensation.