The retirement board, also referred to in this act as the pension board, created hereunder shall be known as “The retirement board” and shall be a corporate body, consisting of 5 members, which shall consist of:

  (1) The treasurer of the city, village or municipality, so affected hereby.

  (2) Two additional members, 1 of whom shall be an active member of and elected by a majority vote of the members of the fire department, and 1 of whom shall be an active member of and elected by a majority vote of the members of the police department under such rules and regulations as the retirement board shall adopt to govern such election. Each such member shall serve for a term of 4 years, except that in the first instance, the member elected by the police department shall serve for a term of 2 years. If in the first instance only the fire department or only the police department is included in the retirement plan, the 2 additional members shall be elected from that department and the candidate receiving the highest number of votes shall be elected for the 4-year term and the candidate receiving the second highest number of votes shall be elected for the 2-year term.

  (3) Two additional members shall be appointed by the legislative body or another person or body authorized by the city or village charter to appoint administrative officials in any city or village affected by the provisions of this act.