xylem [ˈzaɪləm]

例句:

• The xylem of ferns and conifers contains only tracheids.
  蕨类植物和针叶树的木质部仅含有管胞.
  
• The dicotyledonous woody xylem is also absent.
  来自BBC
• Sapwood contains xylem vessels, but not as strong as heartwood.
  边材含有木质导管, 但不如中心木质那样坚硬.
  
• Secondary xylem consists of pitted vessels, parenchyma fibers and rays.
  次生木质部由孔纹导管 、 薄壁组织及射线所组成.
  
• The xylem in trees, through which water rises to the leaves, consists of spaces left by dead cells.
  来自SA
• But later cells, the later xylem cells are much more like a cocktail stirring straw, so very little intercellular space.
  来自SA