Stems and Leaves Flashcards
Major functions of stems
Support, transport, storage, photosynthesis
Determines the pattern of tissues and organs in the plant
Shoot tip
Concentric cylinders vascular arrangement
Ring of xylem and a ring of phloem in concentric circles
Name for the vascular cylinders of both xylem and phloem in concentric arrangement
Stele
Ring of vascular bundles arrangement
Ring of bundles of xylem inside and phloem outside
Name for area between 2 vascular bundles in ring arrangement
Interfascicular region
Scattered vascular bundles
Xylem and phloem bundles scattered and randomly oriented
Copies of SAM at junction of leaf and stem
Axillary buds
Horizontally oriented stem functioning in asexual reproduction
Stolon
Modified stem that has twining shoots that coil and attach to objects
Tendrils
Modified stem into a spiny protruberance
Thorns
Whole stem modified for water storage
Succulent stems
Flattened, photosynthetic stem that can break off for asexual repo
Cladodes/cladophylls
Underground modded stem that never elongates, highly condensed nodes, and fleshy leaves
Bulbs
Underground modded stem that’s horizontal, near or below surface
Rhizome
Underground modded stem that’s vertical, for storage and asexual repo
Corm
Underground modded stem that’s the swollen tip of a stolon, for storage and asex
Tuber
Plant part that attaches leaf to stem
Petiole
Word for a leaf with no petiole
Cessile
Plant part that attaches leaflets of a leaf
Petiolule
Node where leaflets attach
Rachis
Compound leaf where all leaflets arise from common point
Palmate
Compound leaf where leaflets arise from several locations on elongated rachis
Pinnate
Word for the arrangement of leaves
Phyllotaxis
3 types of Phyllotaxis
Opposite
Alternate
Whorled
Palisade Mesophyll
1-cell thick, columnar, upper side of leaf, many chloroplasts
Spongy Mesophyll
Irregular cells with 70% of the space in region empty to facilitate CO2 diffusion
Ring of parenchyma around vascular bundle
Bundle sheath
Leaf in sun
Smaller, thicker cuticles, more palisade Mesophyll
Shade leaf
Bigger, thinner, thinner palisade, maybe chloroplasts in epidermis
Leaf morphology adapted to neither extreme
Mesophytes
Leaf morphology adapted to extreme dry
Xerophytes
Leaf morphology adapted to wet/underwater
Hydrophytes
Xerophyte characteristics
Small thick leaves, large vacuoles, stomates in pits, much support to prevent dessication
Hydrophyte characteristics
Thin, large surface area, no cuticle, lack stomata or stomata on top, less developed parenchyma
Modded leaf for storage
Storage leaves
Modded leaf into sharp protuberance
Spine
Leaf mods for protecting SAM
Bud scales, bracts
Modded leaves for better floral display
Attractive leaves
Modded leaves for climbing(same name as stem)
Tendrils
Modded leaves for trapping water or bugs
Trap leaves
Modded leaves for reproduction
Reproductive leaves
Hormones that stimulate abscission
Auxin, ethylene
Two layers of abscission zone
Separation
Protection
Major functions of leaves
Photosynthesis
Gas exchange
Storage
Vegetative propagation
