ROOTS
ARE THE UNDERGROUND PART OF PLANTS.They have three main
functions .Firs
t,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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