All multiplicative quantum numbers belong to a symmetry (like parity) in which applying the symmetry transformation twice is equivalent to doing nothing (involution).
Moreover, additional to tissue prolapse, postpartum diminishment (involution) of the voluminous milk glands in the breast aggravates the looseness of the suspensory ligaments, and of the inelastic, overstretched skin envelope.
It divides into six or more branches, which enter the hilum of the spleen and ramify throughout its substance, receiving sheaths from an involution of the external fibrous tissue.
