External Structure of the Stem
of a Typical Dicotyledonous Plant
a. Support of main
body of plant & leaves.
b. Conduct water & food.
c. Photosynthesis in new green stems.
Leaf Scar: Heart-shaped scar on
twig where last years leaf grew.
Node: Growth region on stem. Region
around bud or leaf stem.
Bundle Scar: Tiny bumps in leaf
scar where veins enter the leaf from the stem.
Terminal Bud: Bud on end of a branch,
where all of next years length (of branch) is added.
Lateral Bud: Small buds along length
of branch that develop into leaves, lateral branches, or flowers.
Apical Dominance: The terminal bud
dominates all other lateral buds by giving off hormones. If the terminal bud
is cut off, the lateral buds will grow longer.
Girdling: Cutting of bark around
tree into cambium layer kills tree (no sap to roots!).