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www.GOALias.blogspot.comWell, Boojho is right. Plants havepipe-like vessels to transport water andnutrients from the soil. The vessels aremade of special cells, forming thevascular tissue. A tissue is a group ofcells that perform specialised functionin an organism. The vascular tissue forthe transport of water and nutrients in theplant is called the xylem [Fig. 11.7 (a)].The xylem forms a continuousnetwork of channels that connects rootsto the leaves through the stem andbranches and thus transports water tothe entire plant [Fig. 11.7 (b)].Paheli says her mother putsladyfinger and other vegetables inwater if they are somewhat dry.She wants to know how waterenters into them.You know that leaves synthesisefood. The food has to be transported toall parts of the plant. This is done bythe vascular tissue called the phloem.Thus, xylem and phloem transportsubstances in plants.Activity 11.3Take a large potato and peel off its outerskin. Cut one of its ends to make thebase flat. Now make a deep and hollowcavity on the opposite side. Fill half ofthe cavity with sugar solution and markthe level by inserting a pin in the wallof the potato (Fig. 11.8). Put the potatoPotatoSugarsolutionPinWaterFig. 11.8 Transportation of water through cellsinto a dish containing a small amountof water. Make sure that the level of wateris below the level of the pin. Allow theapparatus to stand for a few hours.You would find an increase in thelevel of sugar solution. How did waterget inside the potato? For very shortdistances water can move from one cellto another. In the same way waterreaches xylem vessels of the root fromthe soil [Fig. 11.7 (a)].TranspirationIn Class VI you learnt that plants releasea lot of water by the process oftranspiration.Plants absorb mineral nutrients andwater from the soil. Not all the waterabsorbed is utilised by the plant. Thewater evaporates through the stomatapresent on the surface of the leaves byBoojho wants to know whyplants absorb a large quantityof water from the soil, then giveit off by transpiration!129TRANSPORTATIONIN ANIMALSAND PLANTS129