We see phellem below microscope, it is by by tens of thousands be just as alveolate to do cellular composition, air was filled inside the cell, formed many a airtight gasbag.
英
美
- 我们在显微镜下看软木组织,它是由成千上万个如同蜂窝状的干细胞组成,细胞内布满了空气,形成了一个一个的密闭气囊。