Growth

Meristem: tissue consisting of undifferentiated cells
                     -gives rise to various organs
                     -keeps it growing
Primary Growth: occurs at apical meristems and lengthens stems and roots

 Secondary Growth: increases girth of  root or stem & is a result of activity of vascular cambium

Vascular Cambium: lateral meristem that forms secondary tissue & is located between the xylem and phloem

Cork Cambium: secondary meristem that develops in region outside vascular tissues & produces periderm

Auxin:
   -development of embryo
   -leaf formation
   -phototropism
   -root initiation

Cytokinin:
   -promotes cell division in roots and shoots
   -bud growth
   -leaf senescence

Tropism: turning of all or part of an organism in a particular direction in response to an external stimulus

Bean