Name: Translocation of Mineral Ions
Uploaded: 2019-07-19
Duration: 8 min 6 s
Description: Translocation of mineral ions occurs in the plants through special channels called phloem. Watch this video to learn how the minerals are absorbed and transl...

Question

Describe the factors affecting the transpiration in plants.

Accepted Answer

Stomatal transpiration occurs when stomata are fully open. The increase or decrease in the osmotic concentration of the guard cells affects the opening and closing of stomata and thus the transpiration process. Similarly, Transpiration depends on many other factors such as the rate of evaporation, temperature, light, and wind speed, etc. The factors that affect transpiration are:

1. External factors

Atmospheric humidity- The rate of transpiration is higher in low atmospheric humidity while at higher atmospheric humidity, the atmosphere is moistened, resulting in decreasing the rate of transpiration.

Temperature- Water vapor holding capacity of air is increased at high temperature, resulting in an increase in the rate of transpiration.

Light- The rate of transpiration is faster in blue light than that of red light. Because stomata are completely opened in the blue light.

Wind velocity- Transpiration increases in the beginning at high wind velocity (30 - 35 km. /hour) But later on it causes closure of stomata due to mechanical effect and thus transpiration decrease.

Atmospheric Pressure- At low atmospheric pressure, rate of the diffusion increases and thus, increase the rate of transpiration.

2. Internal factors:

Area of the leaf- The greater the leaf area, the higher will be the water loss due to transpiration.

Stomatal frequency- More is the number of stomata, enhanced transpiration process is likely to take place.

Structure of leaf- The presence of thick cuticle, wax layers, sunken stomata, and trichomes on the surface of leaves reduce the rate of transpiration.

Root-Shoot Ratio- The rate of transpiration decreases with a decrease in root - shoot ratio. The rate of transpiration increases with an increased root-shoot ratio.

Describe the factors affecting the transpiration in plants.

Important Questions on Transport in Plants

Learn and Prepare for any exam you want !