(b) Humidity of the atmosphere: If the air outside is humid the rate of transpiration is reduced, since the outward diffusion … Transpiration occurs because plants take in more water than they actually need at a given time. Dry atmosphere means lack of moisture content in the air. The apparatus shown in the following diagram is Garreau’s potometer designed to demonstrate unequal transpiration from the two surfaces of a dorsiventral leaf Before keeping the leaf in between the cups, anhydrous calcium chloride (CaCl 2) contained in two small vials were weighed and placed in both the cups.The ends of … Function of Transpiration. How Do Plants Lose Water? In dim light or on a cloudy day the stomata are partially closed reducing the rate of transpiration. Transpiration vs humidity. Solution:-(b) temperature is high. However, if the atmosphere is dry, there will be a steep water concentration gradient between the humid inside of the stomata and the outside air and the rate of transpiration will therefore be fast. 3. Since relative humidity is the actual amount of water vapours in the atmosphere at any given time, the rate of transpiration is mainly dependent on it. Similarly, high temperatures evaporate the water at a much higher rate thus again increasing the rate of transpiration. Sunken stomata, as in adelfa or Nerium oleander, also lessen the rate of transpiration by sheltering the boundary layer from wind movement. One of the internal factors which affect the rate of transpiration, is (a) big size of the leaf (b) Colour of the leaf (c) sunken stomata … Any reduction in water in the atmosphere creates a gradient for water to move from the leaf to the atmosphere. 4. Factors that affect the rate of transpiration also affect water uptake by the plant. Due to this, air has a lot of capacity to hold water and thus the rate of transpiration increases. The lower the RH, the less moist the atmosphere and thus, the greater the driving force for transpiration. Figure 5.17: Transpiration vs humidity. However, if the atmosphere is dry, there will be a steep water concentration gradient between the humid inside of the stomata and the outside air and the rate of transpiration will therefore be fast. Thus higher the wind speed, greater is the rate of evaporation. Transpiration is the process by which water contained in plant tissues is lost to the atmosphere by the process of evaporation. If the rate of transpiration increases, the rate of absorption of water by the root increases too. Transpiration is very important for maintaining moisture conditions in the environment. - … The rate of transpiration is more when (a) atmosphere is dry (b) temperature is high (c) humidity is high (d) atmosphere is dry and temperature is high. Solution 1: (a) Open stomata, dry atmosphere and moist soil Question 2: With decrease in atmospheric pressure, the rate of transpiration will (a) increase (b) decrease rapidly (c) decrease slowly (d) remain the same Solution 2: (a) increase Question 3: The rate of transpiration is more when (a) atmosphere is dry (b) … If there is wind, it moves this water vapor laden air away while dry air takes its place. In strong light, the rate of transpiration is more because stomata are wide open. The cuticle, being made of wax, has a limiting effect on the transpiration rate by hampering the diffusion of water vapor to the outside atmosphere. As much as 10 percent of the moisture in the Earth’s atmosphere is from transpiration of water by plants. Rate of transpiration is more when:- (a) atmosphere is dry, (b) temperature is high, (c) humidity is high, (d) atmosphere is high and temperature is high. 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