Is transpiration good or bad for plants? Please be detailed, and it is advisable to have relevant in

Transpiration is a major driving force for water absorption and transport in plants, and transpiration can reduce the temperature of leaves.

However, if the transpiration is too strong, the water of the plant will be dispersed too quickly, which will cause the plant to wilt.

In summary: transpiration is certainly beneficial for plants, with exceptions in special cases.

Yes, we just started, and I am in the second year of junior high school.

Function: It is a major driving force for the absorption and transport of water by plants, and is very helpful for the absorption of minerals and organic matter.

Transpiration of plants is a major driving force for the absorption and transport of water by plants, especially for tall plants, if there is no transpiration, the water absorption process caused by transpiration pull cannot be produced, and the higher parts of the plant cannot obtain water.

Since mineral salts must be dissolved in water in order to be absorbed and run in the body, since transpiration is the driving force for water absorption and flow, minerals are also inhaled and distributed to all parts of the plant body with the absorption and flow of water.

The same goes for the absorption of organic matter by plants and the transport of organic matter through the body. Therefore, transpiration is helpful for the absorption of minerals and organic matter, as well as the transport of these two types of substances in the plant.

Categories: Education, Science, >> Science & Technology.

Problem Sleepy Sen Description:

1。Does air movement affect transpiration?

2。Do you have as many stomata on the front and back of the blade?

It's all a book question).

Analysis: 1Of course it does.

The flow of air accelerates the flow of air near the surface of the leaf, and the humidity, carbon dioxide concentration, and gas temperature of the air on the surface of the leaf are different from that of the atmosphere due to the transpiration of the plant. Specifically, humidity is greater than air humidity and carbon dioxide is higher than the atmosphere. Accelerating the flow rate of air will disturb the air on the surface of the leaf and accelerate the "volatilization" of this air layer, thereby accelerating the transpiration and photosynthesis of plants.

In layman's terms, when the wind is strong, the evaporation rate of water accelerates. That's it.

In short, it is that within a certain range, the proper flow of air will speed up the transpiration of plants.

2.Generally speaking, the front side of the terrestrial plant has more stomata than the back, because the front side receives more sunlight, which is more conducive to absorbing carbon dioxide and photosynthesizing with the plant. For aquatic plants (referring to the leaves that do not appear above the water surface, the same as above when the water surface is exposed), it is difficult to distinguish between the positive and negative leaf surfaces, so the number of stomata is about the same.

Plant transpiration is mainly due to stomatal transpiration, which is significantly regulated by factors such as light, temperature and CO2.

Light is the main regulator of stomatal movement. There are two kinds of effects of light promoting stomatal opening, one is the indirect effect that occurs through photosynthesis; The other is a direct effect that occurs when a light signal is sensed by a photoreceptor.

The effect of light on transpiration is first to cause the opening of the stomata and reduce the internal resistance, thereby enhancing transpiration. Secondly, light can increase the temperature of the atmosphere and the leaves, increase the vapor pressure difference between the inside and outside of the leaves, and accelerate the transpiration rate.

Temperature Stomatal movement is a physiological process related to enzymatic reactions, so temperature has a great influence on the rate of transpiration. When the atmospheric temperature increases, the leaf temperature is 2 10 higher than the air temperature, therefore, the increase of the vapor pressure in the cavity under the stomata is greater than the increase of the air vapor pressure, so that the vapor pressure difference between the inside and outside of the leaf increases, and the transpiration is strengthened. When the temperature is too high, the leaves lose too much water and the stomata close, thus weakening transpiration.

CO2 has a strong effect on stomatal movement, with low concentrations of CO2 promoting stomatal opening, and high concentrations of CO2 causing the stomata to close rapidly (both in light and in the dark). At high concentrations of CO2, the possible causes of stomatal closure are:

High concentrations of CO2 increase plasma membrane permeability, leading to K+ leakage, eliminating solute potential gradients inside and outside the plasma membrane.

CO2 acidifies the cell, affecting the establishment of transmembrane proton concentration differences. Therefore, high CO2 concentrations inhibit stomatal transpiration.

Lighting

Light can increase the transpiration of plants. Light increases the leaf temperature, accelerates the evaporation of mesophyll water, and increases the vapor pressure in the intercellular space and the cavity under the stomata of the mesophyll. The sunlight increases the atmospheric temperature and decreases the relative humidity, which increases the vapor pressure difference between the inside and outside of the leaf and the temperature difference between the leaf and the atmosphere. The light opens the stomata and reduces the impedance of transpiration.

Atmospheric humidity

The greater the relative humidity of the atmosphere, the smaller the vapor pressure difference between the inside and outside of the leaf, and the weaker the transpiration intensity. The relative humidity of the normal leaf stomatal cavity is about 91, and when the atmospheric relative humidity is 40 48, transpiration can be carried out smoothly. The weather is dry, and transpiration is strengthened due to the increase of vapor pressure difference between the inside and outside of the leaf.

Temperature

When the soil temperature increases, it is conducive to the root system to absorb water and promote transpiration. When the temperature rises, the free energy of water increases, the diffusion rate of water molecules accelerates, and the transpiration rate of plants accelerates. Therefore, the temperature increases and transpiration intensifies within a certain range.

Wind

The breeze promotes transpiration because the wind can blow away the water vapor outside the stomata and supplement some water vapor with low relative humidity, which reduces the diffusion resistance inside and outside the leaf and strengthens transpiration. Strong winds cause the stomata to close and the leaf temperature to drop, which in turn weakens transpiration.

Transpiration is affected by a combination of many environmental factors. The changes of crops in one day are: after sunrise in the early morning, the temperature increases, the atmospheric humidity decreases, and the transpiration is enhanced, generally reaching the peak around 2 o'clock in the afternoon, and after 2 o'clock, due to the gradual weakening of light, the water in the plant body decreases, the stomata are gradually closed, the transpiration decreases, and the transpiration decreases to the lowest point after sunset.