Plant morphology - PLSC 214 Exam 1

Mycorrhizae

Fungus that grows in association with the roots of a plant in a symbiotic relationship

Angiosperms

Covered seeds, flowering plants

Gymnosperms

Naked seeds, conifers/cone-bearers

Cotyledon

First leaf or pair of leaves developed by the embryo from a seed

Monocot

Flowering plant embryo developing a single cotyledon

Dicot

Flowering plant embryo developing two cotyledons

Leaf

Includes blade, venation, bud, and petiole

Blade

Portion of leaf distinct from the petiole

Midrib

Main vein running through the center of leaf

Petiole

Stalk of a leaf

Stipule

Leaf-like appendages that occur at the base of the petioles in some leaves

Bud

An undeveloped flower, leafy shoot, or stem

Apex

Tip of the leaf

Sinus

Cleft or recess between two lobes

Lobe

Rounded segments of the leaf with adjacent sinuses

Margin

Outer edge of the leaf

Base

Lowest point of the leaf where it connects to the petiole

Simple Leaf

Bud exists at the base of a single leaflet

Compound Leaf

Located at the base of a leaf containing multiple leaflets

Rachis

Main axis of structure for compound leaves

Palmately Compound

Leaflets coming form one point at the end of the Petiole

Odd Pinnate

Leaflets paired along either side of the central rachis with a terminal non-paired leaflet

Even Pinnate

Leaflets paired along either side of the central rachis with a non terminal leaflet

Bipinnate

Pinnate leaflet structure existing on another pinnate structure

Needle-like Leaves

Leaves that are long and narrow, often evergreen, may be flattened or rounded

Awl-like Leaves

Narrow, flat, stiff, shark-pointed leaves, usually less than ½”

Scale-like Leaves

Small Leaves that are often compressed to the branches

Nodes

Points of attachment for leaves, roots, and flowers

Internodes

Regions in between nodes

Opposite Leaf Arrangement

Leaves and buds exist across from each other on the stem

Alternate Leaf Arrangement

Leaves and buds are arranged in alternating patterns on the stem

Whorled Leaf Arrangement

Three or more leaves and buds arranged a the same point on the stem

Subopposite Leaf Arrangement

Leaves and buds are arranged in patterns that are not truly opposite or alternate

Obovate

Leaf Shape:

Oblanceolate

Leaf Shape:

Obcordate

Leaf Shape:

Oblong

Leaf Shape:

Linear

Leaf Shape:

Ovate

Leaf Shape:

Lanceolate

Leaf Shape:

Cordate

Leaf Shape:

Elliptical

Leaf Shape:

Hastate

Leaf Shape:

Reniform

Leaf Shape:

Cuneate

Leaf Shape:

Peltate

Leaf Shape:

Entire

Leaf Margins:

Serrate

Leaf Margins:

Serrulate

Leaf Margins:

Doubly-Serrate

Leaf Margins:

Dentate

Leaf Margins:

Crenate

Leaf Margins:

Incised

Leaf Margins:

Sinuate

Leaf Margins:

Undulate

Leaf Margins:

Lobed

Leaf Margins:

Acuminate

Leaf Apex:

Acute

Leaf Apex:

Truncate

Leaf Apex:

Emarginate

Leaf Apex:

Mucronate

Leaf Apex:

Cuspidate

Leaf Apex:

Cuneate

Leaf Base:

Acute

Leaf Base:

Rounded

Leaf Base:

Cordate

Leaf Base:

Oblique

Leaf Base:

Sagittate

Leaf Base:

Hastate

Leaf Base:

Truncate

Leaf Base:

Auriculate

Leaf Base:

Parallel Venation

Veins run parallel lines to margin

Pinnate Venation

Veins extend from a midrib toward the edge

Palmate Venation

Veins radiate from a central point in a fan shape away from the petiole

Glabrous

Having smooth, hairless leaf surface

Glutinous

Sticky leaf surface

Scabrose

Rough sandpaper-like leaf surface

Glaucous

Whitish or blueish waxy covering leaf surface

Pubescent

Hairy leaf surface

Uniform Pith

Solid core filled with pith parenchyma (pith cells)

Chambered Pith

Solid Core of pith cells absence, only contains distinct partitions (think bamboo)

Hollow Pith

Disintegrated pith with a large central cavity

Evacuated/Spongey Pith

Pith cells are perforated with holes

Narrowly Conical

Bud morphology:

Ovoid

Bud morphology:

Conical

Bud Morphology:

One-scaled

Bud morphology:

Superposed

Bud morphology:

Accessory

Bud morphology:

Taproot

Sends a main root deep into the soil in search for water/nutrients

Fibrous Root

Roots grow down and out in search of nutrients and water

Rhizomes

Modified stem that grows laterally under the surface, sending out new roots and shoots at nodes

Stolons

Horizontal stem growing laterally along the group, sending out new roots and shoots at nodes

Tubers

Swollen, fleshy root that stores nutrients

Bulbs

Compressed stems growing underground that stores nutrients and surrounds a flower bud

Smooth Bark

Bark with little to no texture, common among younger trees

Papery Bark

Bark with horizontal peeling in large sheets or thin strips

Knobby

Bark that looks warty or bumpy

Furrowed

Fissured bark, similar to plow lines, deeper with age, sometimes in diamond pattern

Pistil

Female reproductive organ of a flower, consists of ovary, style, and stigma