primary xylem meaning in English
初生木质部
原始木质部 由原始形成层分裂之木质部，属初生永久组织之一份子
Examples
- Primary xylem xylem derived from the procambium in the young plant
初生木质部：指幼嫩植物中来源于原形成层的木质部。 - Protoxylem the primary xylem elements that are formed from the procambium first
原生木质部：初生木质部的成分，最早由原形成层形成。 - In nonwoody plants the primary xylem is the only water - conducting tissue , but in mature plants with secondary growth this function is mostly taken over by the secondary xylem
在尚未木质化的植物中，初生木质部是唯一的输水组织，但在具有次生生长的成熟植物中，该功能大多由次生木质部行使。 - The process of vessel element ' s promotion , formation and connection in primary xylem of antirrhinum majus , a model plant , was observed through micropolariscope and bright - field microscope
利用偏光显微镜和明场显微镜，首次报道了模式植物金鱼草幼苗初生维管系统木质部导管分子的发育、形成和连接过程。 - We have observed the following characteristics of anatomical structure and development : ( 1 ) the primary roots belong to archetype and the lateral roots occur in the position toward the xylem of the vascular cylinder ; ( 2 ) the root endodermis consists of thicken casparian strips , and there are from two lo four layers parenchyma cells near the pericycle ; ( 3 ) the pith and resins canals are absent in the toots ; ( 4 ) secondary structure occurs in the root hair zone , and vascular cambium is formed from the parenchyma cells between the primary xylem and primary phloem ; ( 5 ) tanning materials are abundant in pericycle cells and phelloderm cells ; ( 6 ) sclereids are found in secondary phloem , and rays are rather rich in secondary xylem
结果表明：气生不定根具有以下结构特征和发育特点： ( 1 )根为二原型，侧根正对着木质部发生； ( 2 )幼根内皮层细胞具凯氏带加厚，维管柱内紧挨中柱鞘内侧具有2 ~ 4层大型薄壁细胞； ( 2 )根中无髓和树脂道； ( 4 )次生结构发生于根毛区，维管形成层由初生木质部和初生韧皮部之间的薄壁细胞转化形成； ( 5 )中柱鞘和栓内层细胞富含单宁类物质； ( 6 )次生韧皮部有石细胞，次生木质部射线发达。