- 作者: 施景垣
- 作者服務機構: 中央研究院植物研究所
- 中文摘要: 以電子顯微鏡視察棉之形成層細胞發育成篩管的變化。最初的變化是細胞壁加厚,在其附近有微小管。色素體內有電子不透物的聚積。在兩端的細胞壁有嵌醣的沈積,並漸形成篩孔。然後才是細胞質內胞器及膜的變化。中央部的液泡其膜收縮退化。內質網變成疏鬆,膨脹,表面上的粒線體消失。篩管內網狀物在篩部發育的初期即出現,以一端附於原生質膜。當發育初期細胞核漸退化時,核內的核仁消失。 纖維狀物散布於整個空間。含有澱粉的色素體一直存在。粒線體數量雖少但保持完整。
- 英文摘要: Development of a sieve tube member from a cambial cell of cottonplants has been studied with an electron microscope. The first detectablechanges in this cell are the thickening of cell wall and the accumulation ofelectrondense bodies in the stroma of the plastids. The microtubules arevisible next to the thickening cell wall. In the end wall, callose depositsassociated with sieve pore formation during wall thickening are observedFurther stages of sieve tube development involve marked alteration of or-ganells and membrane system in the cytoplasm. The tonoplast of the centralvacuole contracts and degenerates.Group of ER becomes loose and dist-ended and loses its surface ribosomes. Structures termed sieve tube reticulumoriginate at a very early stage of sieve element development. They are al-ways attached to the plasmalemma at one end. The nucleolus of the nucleusis extruded in the early stage of development while the remaining nucleusdegenerates and disappears. The fibrilar substances are dispersed through-out the lumen. Plastids with starch inclusions persist.Mitochondria areintact although few in number.
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