The Commission consists of the following 17 members: As ex officio members, the seven regional members of the State Roads Commission; and Ten members appointed by the Governor with the advice of the Secretary. An appointed member may not be an officer or employee of the Department. Each appointed member shall be a resident of this State and have interest and, preferably, experience in at least one of the fields under the jurisdiction of the Department. Each appointed member serves for a term of 3 years and until his successor is appointed and qualifies. The terms of appointed members shall be staggered as required by the original appointments to the Commission, three of which were made for a 3-year term, four of which were made for a 2-year term, and three of which were made for a 1-year term. A member appointed to fill a vacancy in an unexpired term serves only for the remainder of that term.