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A Venturi Effect Can Help Cure Our Trees
Published on: October 1, 2013
控制植物中西液压阻力的水凝控制
M A Zwieniecki1, P J Melcher, N M Michele Holbrook
1Organismic and Evolutionary Biology, Harvard University, 16 Divinity Avenue, Cambridge, MA 02138, USA. mzwienie@oeb.harvard.edu
概括
通过增加离子度,植物体的液压阻力迅速降低. 边界坑中的这种离子介导的水凝反应表明植物可以积极调节水流.
科学领域:
- 植物生理学 植物生理学
- 克西勒姆液压系统是什么
- 生物物理学的生物物理.
背景情况:
- 体传统上被视为植物水运输的被动管道.
- 了解体内的水流调节对于植物的生存和生产力至关重要.
研究的目的:
- 为了研究离子度对植物体液压电阻的影响.
- 探索离子诱导的液压导电性变化的潜在机制.
主要方法:
- 在不同的离子度,pH值和非极性溶剂下测量植物树脂中的液压阻力.
- 将观察到的效应定位到交界的边缘坑中.
主要成果:
- 离子度的增加导致了快速,实质性和可逆的体液压阻力下降.
- 观察到的变化与水凝介导的过程一致,特别是pectin膨胀和脱水.
- 该效应局限于介质边界坑膜内的微通道.
结论:
- 植物体不是一个惰性管道系统,而是具有离子介导的调节机制.
- 边界坑内的pectin水凝在调节液压电阻方面发挥着关键作用.
- 这种机制为植物提供了一条新的途径,可以积极调节它们的内部水流.
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