服务承诺





51Due提供Essay,Paper,Report,Assignment等学科作业的代写与辅导,同时涵盖Personal Statement,转学申请等留学文书代写。




私人订制你的未来职场 世界名企,高端行业岗位等 在新的起点上实现更高水平的发展




Transpiration
2013-11-13 来源: 类别: 更多范文
Transpiration
Most plants and trees get the water and minerals they need to survive from their roots. Basically, water is absorbed from the soil then travels up through the plant roots to the stems and then to the leaves. Plants have to create pressure in the system to move water from the roots up to the leaves and this is difficult because plants have no heart or internal pump to move the water. So, you can imagine it must take lots of effort for water to rise to the top of a plant, let alone to the top of a tree that is 300 or more feet tall. In fact, plants and trees actually acquire water by osmosis through root hairs, water is then transported or pulled upward by a process called transpiration. The pulling force of transpiration involves water potential, energy of evaporation, surface tension and hydrogen bonds. (Solomon et al 2002).
Water mainly enters a plant through tiny root hairs growing on the root. Water and other dissolved minerals then move from the root tissues to the vascular cylinder. Plants have two main types of vascular tissue that transport water, called xylem and phloem. Xylem is the vascular
water, roots, root, transpiration, plants, leaves, cells, pressure, plant, potential, xylem, trees, through, theory, solomon, soil, molecules, et, cohesion, called, al, 2002, tree, transport, osmosis, fungi, evaporation, because, way, vascular, top, tension, process, nutrients, move
