H? th?ng này ??m b?o r?ng l??ng ch?t l?ng ???c b?m ra luôn ?n ??nh và phù h?p v?i yêu c?u s? d?ng.This anchorage makes it possible for it to operate successfully during the breathing cycle, contracting and relaxing rhythmically to aid airflow into and out of the lungs.The anterior connections lengthen in the lessen ribs and converge with the x