Meristems are parts of the plant where mitotic activity is active. Undifferentiated self-renewing cells are found in the meristems. There are two types of meristems: apical meristems (shoot apical meristem/SAM and root apical meristem/RAM) and lateral meristem (secondary growth).
The apical meristems are found in the shoots and the roots and produce three types of primary meristems: protoderm, ground meristem, and procambium.
Features of apical meristems (SAM/RAM):
• adds length to the plant, ,(1)
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• Forms the epidermis and the ground tissues (ground meristem) ,(3)
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• Generates the protoderm, procambium, and the ground meristems ,(5)
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• Produces the primary plant body ,(7)
The lateral meristems produce the secondary growth (increase in girth/diameter) of the plants. It includes vascular cambium (found in the procambium and pericycle of the roots) and cork cambium (found in the pericycle of the roots and the parenchymal cells of the cortex in stems).
Features of lateral meristems:
• adds diameter to the plant, ,(2)
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• produces the secondary plant body ,(4)
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• cork cambium and vascular cambium, ,(6)
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• produces bark ,(8)