The directors of a corporation shall at all times include representatives of:
(1) Administrators or trustees of hospitals which have contracted with the corporation to render hospital service to subscribers, if the corporation is a hospital service corporation or a hospital and medical service corporation;
(2) Physicians and surgeons licensed to practice in this state who have contracted with the corporation to render medical service to subscribers, if the corporation is a medical service corporation or a hospital and medical service corporation; and
(3) The general public, exclusive of hospital representatives and physicians.