Hydraulic resistances (reciprocals of hydraulic conductivities) of the cell (Lp-1), the cell wall (Lpw-1), the membrane (Lpm-1), the plasma membrane (Lppm-1), and the tonoplast (Lptp-1) were determined in individual internodal cells of Chara corallina and their dependence on the cell age was studied. The thickness of the cell wall (d) was adopted as an index of the cell age, since the cell wall of spring-grown young cells (sg-cells) was found to be significantly thinner than that of winter-spent old cells (ws-cells). Both Lpw-1 and Lpm-1 were found to increase with cell age. Since Lpm-1 is the sum of Lppm-1 and Lptp-1, their dependence on the wall thickness was studied. It was found that both Lppm-1 and Lptp-1 increase with cell age using d as a proxy and that the former is distinctly higher than the latter. The ratio Lppm-1/Lptp-1 amounts to 30 for 5 μm of d, indicating that the tonoplast is a negligible barrier to osmotic water flow. The ratio decreases with the increase in d and amounts to 5.0 for 11 μm of d, showing that the tonoplast ages faster than the plasma membrane. The physiological meaning of the age dependence of hydraulic resistance of the tonoplast was discussed in terms of the role of the vacuole in the osmoregulation of the cytoplasm.

中文翻译：

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珊瑚虫细胞中质膜和液泡膜（液泡膜）的水力阻力的年龄依赖性

细胞 (Lp-1)、细胞壁 (Lpw-1)、细胞膜 (Lpm-1)、质膜 (Lppm-1) 和液泡膜 (Lptp-1) 的水力阻力（水力传导率的倒数） ) 在 Chara corallina 的单个节间细胞中测定，​​并研究了它们对细胞年龄的依赖性。细胞壁的厚度 (d) 被用作细胞年龄的指标，因为发现春季生长的年轻细胞 (sg-cells) 的细胞壁明显比冬季衰老细胞 (ws) 的细胞壁薄-细胞）。发现 Lpw-1 和 Lpm-1 都随着细胞年龄的增长而增加。由于 Lpm-1 是 Lppm-1 和 Lptp-1 的总和，因此研究了它们对壁厚的依赖性。发现使用 d 作为代理，Lppm-1 和 Lptp-1 都随着细胞年龄而增加，并且前者明显高于后者。对于 5 μm 的 d，Lppm-1/Lptp-1 的比率为 30，表明液泡膜对渗透水流的屏障可以忽略不计。该比率随着 d 的增加而降低，对于 11 μm 的 d，该比率为 5.0，表明液泡膜比质膜老化得更快。根据液泡在细胞质渗透调节中的作用，讨论了液泡体的水力阻力的年龄依赖性的生理意义。