ROOTS ARE THE UNDERGROUND PART OF PLANTS.They have three main functions .First,they anchor the plant in the soil.Second , they absorb water and minerals from the space between soil particles ;the roots' absorptive properties are increased by root hair ,which grows behind the root tips , allowing maximum uptake of vital substances .Third , the root is the part of the plant's transport system :xylem carries water and minerals from the root to the stem and leaves,and phloem carries nutrients from the leaves to all parts of the root system.In addition , some roots (e.g carrots)are food stores.Roots have an outer epidermis covering a cortex of parenchyma(packing tissue ) and a central cylinder of vascular tissue .This arrangement helps the roots resist the force of compression as they grow through the soil.
INDUSTRIAL REVOLUTION Starts in Europe particularly in England in eighteen century.It changed the whole of Europe and England 's economy.During this period New machines are invented in England to speed up the spinning of wool and cotton .At first they were powered by water wheels but later steam engines are developed.Iron become cheaper and stronger as Iron making techniques improved.Canals are dug to carry coal from the mines and to transport finished goods.After ...
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