(a) State whether the following statements are True (T) or False (F)? Hence, the stoma from the diagram can be of a monocot leaf or of a dicot leaf. After few hours, CaCl2 vials were taken out and weighed again. Give a suitable explanation for the following: (a) A higher rate of transpiration is recorded on a windy day rather than on a calm day. More the, (e) Cork and Bark of trees are tissues of old woody stems. (2003) provided that a single corn plant transpired almost 500 liters of water during a 4-month growing period. Set-up B. (g) The structure in a leaf that allows guttation. Leaves of some plants wilt during midday and recover in the evening. Potometer is a device that measures the rate of water intake by a plant (L. poton: drink, meter: measure), and this water intake is almost equal to the water lost through transpiration. Question A.8. It evaporates most of the water and allows more molecular space for more to come. In the absence of transpiration, excess water will get accumulated in the plant cells, and the cells will eventually burst. Ganong’s potometer is used to measure the rate of water intake by a plant. Solution:-. The loss in weight by the plant during that time is due to loss of water by transpiration. Transpiration helps in creating suction force and in eliminating excess water. Briefly explain how the rate of transpiration is affected by: Of the water given to a plant, 97 to 99.5% is lost to transpiration and guttation, a process where plants exude water droplets. The soil surface and the pot should be fully covered to prevent evaporation from the surfaces other than the plant. Soil Water Content: It also cause the stomata to open, thus more transpiration occurs during the day and the rate is higher on a sunny day compared to a cold dull day. The pot is covered with a plastic sheet to prevent evaporation of water from the soil. Solution:-, Leaf spines and protection and reduced transpiration, (c) Lenticels and…………………………………. Thus, the weight of the entire set will decrease. Best Answer (d) hot, dry and windy . Fewer stomata:- The number of stomata may be reduced. gallons of water every day through the process of transpiration, the evaporation of water ... where it joins the fast moving column of water or transpiration stream, headed to the leaves. 9. Transpiration is the loss of water as water vapour from the aerial parts of the plant. Hence a huge amount of water is escaped into the atmosphere by forests. The remaining 97–99.5% is lost by transpiration and guttation. Transpiration, in botany, a plant’s loss of water, mainly though the stomates of leaves. As transpiration proceeds, i.e., as the water is lost from the twig, a suction force is set up which pulls the water from the beaker and the bubble in the capillary tube moves along. A humid environment hampers transpiration while the roots continue to absorb water from the soil. The first bell jar (A) would show water vapour condensing on its inner walls. sun is mostly behind the clouds making evaporation difficult. Most of the transpiration in tall trees occurs through (a) Stomata (b) Lenticels (c) Cuticle (d) Bark. High humidity in the air reduces the rate of outward diffusion of the internal water vapour across stomata, thereby reducing the rate of transpiration. Your email address will not be published. As the stomata open during the daytime, the diffusion of gases in and out starts fulfilling the need for photosynthesis as well as allowing transpiration. The ends of the cups were closed with corks through which two mercury manometers were connected. Hence, the water in the test will get reduced. (g) On a bright sunny day, the leaves of certain plants roll up. Solution:-. Closing of stomata and shedding of leaves reduce transpiration. 9. Following are the steps which will help you understand the complete process. Slowest transpiration rate in the plant that had the bag around it. Solution:-(d) hot, dry and windy. There are more stomatal openings on the lower surface of a dorsiventral leaf and therefore, more transpiration occurs from the lower surface. List any three major factors that accelerate the rate of transpiration. Solution:-(b) Lenticels. This would prevent the escape of water vapour from the pot. (B) coated on the lower surface. force and in eliminating excess…………. Temperature Plants transpire more rapidly at higher temperatures because water evaporates more rapidly as the temperature rises. (b) Oil is put on the surface of water to prevent loss of water by evaporation. In test tube is transpiration will be fastest when the day is measure the pressure exerted by the roots continue to absorb.! The two parts of the day, when the transpiration rate understand and crack questions... 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