The sternal portion lowers the costal cartilages, facilitating inhalation by expanding the upper body cavity.Màng b?m là b? ph?n ti?p xúc tr?c ti?p v?i dung d?ch, l?i ph?i dao ??ng qua l?i liên t?c, l?p ?i l?p l?i su?t one chu kì, nên ch?t l??ng c?a màng b?m r?t ???c quan tâm.The diaphragm is found within the inferior-most facet of the ribc