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Explore the intricate structures of plant shoots and stems in this detailed guide, including shoot apical meristem, leaf components, vascular tissue, and stem morphology of dicot and monocot plants.
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PLANTS (External & Internal Structures) (Part 2)
shoot apical meristem terminal bud leaf axillary bud blade vascular tissue petiole node Shoot system internode vascular tissue vascular tissue Root system root hair dermal tissue root apical meristem ground tissue root cap root tip vascular tissue
Morphology of a Dicot Stem
shoot apical meristem leaf scar node bundle scar internode lenticel
Shoot apical meristem Leafprimordium Youngleaf Axillarybud Magnified section of the shoot apical meristem
Meristematic region Enlargement region Protoderm epidermis cortex Ground meristem pith phloem Procambium vascular cambium xylem
Morphology of a Monocot Stem
Intercalary Meristem • Occur only in monocot (particularly grass) stems at the base of nodes and leaf blades. • Capable of cell division and allow for rapid growth and regrowth of many monocots. • Leaf regrowth in grasses evolved in response to damage by grazing herbivores.
vascular bundle bundle sheath companion cell phloem sieve tube pitted vessel xylem annular vessel air space
vascular bundle phloem fiber phloem parenchyma sieve tube companion cell vascular cambium tracheid vessel xylem parenchyma xylem fiber
Vascular bundle of a dicot stem phloem vascular cambium interfascicular cambium fascicular cambium xylem
Woody dicot stem Periderm Primary phloem Secondary phloem Secondary xylem Primary xylem pith
lenticels phellem phellogen phelloderm
Bark Sapwood Annual rings Heartwood
For Support Squash (Cucurbita sp.) Morning Glory (Ipomea sp.) Tendrils Twines
For Support Hydrangea (Hydrangea petiolaris) Bougainvillea (Bougainvillea sp.) Clinging roots at the nodes Scramblers (Hooks)
For Photosynthesis Mimosa (Acacia cyanophylla) Stick plant (Euphorbia tirucalli) Phylloclades – green, flattened, thin, leaf-like structures Green stem
For Protection For Storage Onion (Allium cepa) Rose (Rosa sp.) Enlarged, thickened of fleshy subterranean stem Thorns
For Reproduction Strawberry (Fragania sp.) Bermuda grass (Cynodon dactylon) runners stolons