S.4 兩條關於Plant 的 Transpiration 的問題!!
1.) Transpiration 的好處/作用是甚麼??
2.) 植物(們)可唔可以冇左 Transpiration 呢樣野??
註: 如可以的話, 請提供中英對照的答案, 因本人不太懂詮釋。謝謝!
- scgaw2002Lv 41 十年前最愛解答
There are three advantages:
First, plants can make use of transpiration to evaporate excess water to the surrounding. This can lose excess heat energy through water evaporation.
But the most important is, when a transpiration pull is formed, water is drawn from cells to cells. When water is drawn near root cells, minerals such as nitrate ions are also drawn from it and make a steeper concentration gradient which can let minerals diffuse in root cells.(But minerals are absorbed from the soil mainly by active transport.)
Transpiration pull is an important force for the transport of water and dissolved minerals in a flowering plant.As water is lost by the plant through transpiration, this occurs mainly through the stomata in the leaves, water is thus drawn continuously from the roots through xylem vessels.
The xylem vessels formed continuous tubes from the roots , along the stems to the leaves and other plant organs. Water togther with dissolved minerals are transported as a continuous stream inside.
Third, it's to compensate the lose of water. As water is lost continuously, but not enough water is absorbed, water lost is faster than water gained,cells will become flaccid and plants will be wilted since it was dehydrated.Aims to reduce water loss,this will contribute to plants close its stomata and reduce gas exchange and hinder photosynthesis.In young plants, a transpiration pull can help to provide water to cells' turgidity. It can help to absorb more sunlight.(In mature plants, they are supported by rigid xylem.)
第三，這是為了補償水份的流失。由於水不斷地流失，但是吸收的卻不足夠，造成' 水失大於水得' ，故此細胞會變的軟弱和植物會因此而凋萎，缺水正是它的原因。為了減少水份流失，這會導致植物的氣孔緊閉，因而減少氣體交換，與及妨礙光合作用。在年幼的植物中，蒸騰牽引力內幫助提供水份給細胞令它們硬脹。這樣可以幫助吸收多些陽光。(在成熟的植物中，它們是由堅硬的木質部支撐著的。)
These are all the benefits what I know of transpiration over plants.
2006-11-20 23:17:45 補充：
2006-11-20 23:18:09 補充：
Just like what I've said, if a lack of transpiration in plants, they will become wilted, till death. As they only rely on diffusion, rate of water transport is much lower, so the water lost is faster than water gained. If plants have no transpiration, they will die eventually due to dehydration.
2006-11-26 17:55:34 補充：
- 1 十年前
Transpiration provide transpiration pull which provide a force to "suck up" water from the root to top of the tree in the xylem.
Transpiration can also help to cool down a plant in a hot day.
Without transpiration, the plant may have very low efficiency in water transport.