【摘要】 本文是小麦叶片细胞研究的继续。通过电子显微镜观察和光合功能的测定发现:冬小麦植株个体发育过程中,各层次叶片叶肉细胞叶绿体的超微结构随叶位的逐渐上升而渐趋于复杂化,其光合功能也相应地增强,至旗叶最为显著。具体表现为基粒片层(grana lamella)、基质片层(stroma lamella)的数目随叶位上升而增多;基质也随之渐浓;Hill 反应和光合磷酸化活性也相应地提高很多。此外,高叶位叶片特别是旗叶,在叶绿体旁出现的线粒体较低叶位的多,其呼吸强度比第五叶相应地高出几乎一倍。上述结构和功能的密切相关及其从简单到复杂这一自然规律的揭示,对采取措施加以调节控制,是具有重要意义的。更多还原

【Abstract】 This paper deals with the function of chloroplasts from the mesophyll cells of winter wheat Nongda 311 as a continuation of our previous studies on the leaf cells of the same species. Samples of leaves were taken for electron microscopy and photosynthetic deter- minations:It is found that the ultrastructures of chloroplasts from different ranks of leaves very in complexity in an ascending order.The stroma of chloroplasts from the upper-ranked cells are heavily stained as shown by their high content of ribosomes and high consistaney of the mobile phase.The grana lamellae in the flag leaf chloroplasts are thickly stacked against a few disks in the grana of 5 th leaf.The rate of Hill reac- tion and photophosphorylation of the flag leaf is higher than that of the 5th leaf. The mitochondria in the flag leaf cells are large and numerous as compared to these from the 5th leaf.The respiration of the flag leaf is nearly two fold higher than that of the 5th leaf. To sum up our data,we see that the close association between structure and func- tion has gone through a series of changes from the simple to the complex.It is our task to reveal the changes in detail and take measures to regulate the changes,for it is of practical importance.更多还原