BioCoach Activity

Concept 7: Primary Growth

Primary growth is the lengthening of the stem and roots.

All plant growth occurs by cell division and cell elongation. Cell division occurs primarily in regions of undifferentiated cells known as meristems.

Cell division in the apical meristems and subsequent elongation and maturation of the new cells produces primary growth.

The other type of growth, secondary growth, is the increase in girth of stems and roots.

Primary Growth and the Location of Apical Meristems Cell Elongation
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Notice that the internode distance increases during primary growth (elongation), but then this distance becomes set.