Plant Morphology
Basic Plant Parts:
Root - absorbing/anchoring organ (sometimes
storage)
Stem - supportive, conductive organ (sometimes
storage)
Leaf - photosynthetic organ (sometimes
modified)
Shoot
= stem + associated leaves
Bud
= immature shoot,
usually with protective scale leaves
Each leaf
primordium
develops into
one leaf.
Caryota sp.
Arecaceae
Branch
= elongated shoot, arising from bud
Plant Habit
Herb - plant with annual above-ground parts
Vine - weak stems, supported by another pl.
Shrub - woody, >1 trunk
Tree - woody, 1 trunk
Root Types/Parts
taproot
fibrous roots
Root Types/Parts
storage roots Raphanus sativus, radish
Stem (Shoot) Types
bulb
corm
(mostly leaves)
(mostly stem)
both underground storage stems
Stem (Shoot) Types
horizontal, thickened, storage,
underground
develops from
stem tip
long internodes,
ends in plantlet
sharp-pointed
stem
Leaf Structural Type
Leaf Structural Type
Stipular Spine - Euphorbia spp. (Euphorbiaceae)
Leaf Structural Type
Leaf Spine (arising from areole) - Cactaceae
Leaf Structural Type
Tendril - Lathyrus (Fabaceae)
Leaf Structural Type
Bract
-modified, usually reduced leaf
associated with flowers
Bud Scale
-modified leaf functioning to
protect apical meristem of bud
Leaf Type / Parts
simple - blade not divided into leaflets
compound-leaf divided into discrete leaflets
Leaf Type / Parts
simple
pinnately
compound
bipinnately
compound
Leaf Type / Parts
ternate/
trifoliolate
palmate
leaf arrangement
alternate
spiral
1 leaf / node
opposite
2 leaves / node
whorled
3+ leaves / node
Leaf Venation
2 major types:
parallel - monocots
netted - eudicots
vestiture
= cover of plant "hairs" (trichomes)
glabrous - smooth, with no trichomes
glaucous - waxy coating
viscid - sticky secretion