a. As to trustees to be elected by the members or by the board of trustees, a corporation may provide in its certificate of incorporation or its bylaws for the classification of its trustees in respect to the time for which they shall severally hold office, but a class of trustees shall not hold office for a term shorter than 1 year or longer than 6 years. The term of office of at least one class shall expire every 2 years. A classification of trustees shall not be effective prior to the first annual or biennial meeting of members or the board of trustees.
b. Any corporation having more than one class of members may provide in its certificate of incorporation or its bylaws for the election of one or more trustees by the members of any class to the exclusion of members of other classes of members.