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Transportation in plant explain for a 5 marks

Answer» TRANSPORTATION IN PLANTSSoil is the natural and richest source of raw material for plants.Raw materials like nitrogen, phosphorous and other minerals are absorbed by plants from soil by roots.Plants absorb water and minerals from soil by roots and transport to the leaves.As the distance between roots and leaves is large, diffusion is not sufficient to provide raw materials to leaves and energy to roots.Plants use slow transport system but large as required in tall plants to transport energy from leaves and raw materials form roots.A group of special cells forming vascular tissue transport water and nutrients to all the cells of the plants.Two types of vascular tissues are xylem and phloem.Xylem transports water and minerals obtained from the soil.Phloem transports products of photosynthesis from the leaves to other parts of the plant.Vessels, tracheids of the roots, stems and leaves are connected to form a continuous system in xylem cells to transport water to all the parts of the plants.Cells in the roots which are in contact with the soil take up ions which creates a difference of concentration between the roots and the soil and therefore water moves to the roots to eliminate the difference.Water is moved into xylem of roots and from where it is pushed upward.Plants use different mechanisms to pull water upwards through xylem like-\tWater which is lost through stomata is replaced by water absorbed by the roots.\tEvaporation of water from leaf creates a suction force which pulls water.The loss of water in the form of water vapor is calledImportance of transpiration-\tRegulates temperature.\tHelps in absorption of water and upward movement of water and minerals.When stomata are open during the day, large amount of water is lost and thus upward movement of water also becomes more.Phloem transports soluble products of photosynthesis, amino acids, and other substances.The transport of soluble products of photosynthesis is called\xa0translocation.The substances are transported to the storage organs of roots, fruits and seeds.The translocation takes place in the sieve tubes with the help of adjacent companion cells.The movement of substances is bidirectional i.e both upward and downward.Energy from ATP is utilized for translocation.Materials like sucrose move to phloem using energy, increasing the osmotic pressure of the tissue causing water to move and materials in the phloem to tissues according to the plant’s needs.Example- when the buds grow t


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