2019-03-01 Biology Times

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Biology Times March 19

The primary growth of the plant body is brought about by the apical meristem. Sometimes, as in monocots
and vascular cryptogams, the primary structure is permanent. There will not be any secondary growth
brought about by secondary meristems. But, in dicotyledonous angiosperms the primary permanent tissues
constitute only the fundamental parts of the plant body. Further growth in thickness is always by secondary
meristems. This type of growth in girth is brought about by a secondary meristem, is called secondary
Secondary growth may be classified into two types viz., Normal and Anamolous. Any secondary growth
brought about by a fascicular cambium (inner or intra) is called normal. Secondary growth of vasculature
brought about by extrafascicular cambia (arising either in the pith or in the cortex) is called anomalous.

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