UTK EEB:330 Botany Terms

Internode

The portion of the stem between two nodes or points of leaf insertion.

Monoecious

Having male and female flowers on the same plant. (both unisexual individually)

Peduncle

Branch that supports the entire inflorescence.

Petiole

A leaf stalk.

Receptacle

The end of the stem to which flower parts are attached.

Tepals

Sepals and petals that look the same.

Terminal Flowers

The flower at the top of the stem and other flowers.

Achene

Small, dry, single-chambered, one-seeded fruit that does not split open when mature, with the seed coat and ovary wall separate.

Aggregate Fruit

A compound fruit derived from the coherence of two or more simple, superior ovaries of a single flower.

Berry

Pulpy or juicy, multi-seeded, indehiscent fruit.

Capsule

A dry, dehiscent fruit derived from two or more carpels.

Caryopsis

Drupe

A fleshy, pulpy, one-seeded fruit in which the seed has a protective stony covering.

Follicle

A dry, single-chambered pod-like fruit, splitting open along a single line on one side at maturity.

Locule

A compartment, cavity, or cell of an ovary, fruit, or anther.

Legume

A dry fruit from a simple pistil that opens along two lines or sutures.

Loment

A type of legume fruit with constrictions between the seeds.

Multiple Fruit

A fruit derived from the fusion of the ovaries of numerous flowers; a ripened inflorescence.

Nut/Nutlet

A hard, dry, indehiscent, one-seeded fruit derived from a two-to-many carpellate ovary.

Pome

A fleshy, indescendent fruit derived from an inferior ovary and surrounded by an adnate hypanthium.

Samara

An indehiscent, single-seeded, dry-fruit with a prominent wing.

Schizocarp

A dry fruit splitting into two or more indehiscent segments or seeds.

Silique

A pod-like fruit of certain members of the Mustard family, splitting longitudinally, leaving a center partition with seeds.

Simple Fruit

Undivided fruit.

Deciduous

Falling after competition of its normal function, often at the approach of a dormant season.

Oxalic Acid

Acts as a defense mechanism against herbivores. When eaten, they cause immediate physical pain.

Urushiol

A colorless-to-pale-yellow, oily organic mixture found in the sap that causes severe itching, redness, swelling, and fluid-filled blisters when it comes into contact with skin. (Toxicodendron)fluid-filled blisters

Bract

A reduced leaf at the base of a flower or an inflorescence.

Fascicles

A small bundle or dense, close cluster.

Plication

Folded; fan-like.

Chasmogamous Flowers

With pollination after the flower opens.

Cleistogamous Flowers

Bearing self-pollinated flowers that do not open.

Cross-pollination/Outcrossing

The transfer of pollen from one flower to the stigma of another.

Self-pollination/Inbreeding

When plants take pollen from their anther and transfer it to the stigma of the same flower or a different flower on the same plant.

Haustorium

A specialized rootlike or branchlike organ that parasitic plants use to penetrate a host organism and absorb water, minerals, and organic nutrients.

Diadelphous

Filaments united into two bundles; nine united and one free filaments.

Monadelphous

Filaments united into one bundle with sheath continuous or split.

Epidermal Extensions

Outgrowths of the outer epidermal layer that serve critical functions like water absorption, protection, and defense.

Porate

Anthers that open via terminal or apical pores rather than splitting open longitudinally.

Terminal Spike

At the apex or tip.

Verticillasters

Arranged in compressed whorls.

Allelopathy

When a plant releases a biochemical compound into the environment around it that kills off other plants surrounding it.

Early Leaf-Out

A tree or plant sprouts and opens its new leaf buds earlier in the spring or earlier than its usual historical average.

Explosive Dehiscence

Mature plant fruits, pods, or capsules split along built-in lines of weakness violently, catapulting seeds away from the parent plant.

Infructescence

An inflorescence in fruiting stage.

Areola

A clearly delineated area on a surface such as a seed of leaf.

Compressed Stem

A plant stem with very short internodes.

Convergent Evolution

The independent evolution of similar traits or features in unrelated or distantly related species.

Cyathium

Reduced inflorescence of cymes. Inflorescence of Euphorbaceae.

Mericarp

An individual carpel that separates in a compound fruit.

Spines

Modified leaves or modified stipules.

Biennial

Living for 2 years. Only flowering the 1st year and bearing fruit the 2nd.

Bipinnate Leaves

Twice pinnate.

Tri-pinnate Leaves

Three times pinnate, with leaflets twice divided again.

Dissected Leaves

A simple leaf with deep lobes that make it look like it might be compound.

Stolons

Connecting stems above ground.

Rhizomes

Connecting stems underground.

Spathe

Bract beneath inflorescence or flower.

Cypsela

An achene with an adherent calyx or pappus.

Air Roots

Any plant root that grow above the ground, water or soil.

Anther Cap

The lid-like or cap-like tissue structure at the tip of an orchid’s flower column that covers and protects the pollinia until ready to spread.

Chaffy Bract

Thin, dry scales or bracts; often used for the bracts in the flower head of Asteraceae.

Column (Gyandry/Gyandrium)

The central part of an orchid flower, in which the stamen, style, and stigma are united into a common structure.

Epiphyte vs. Terrestrial

An epiphyte is a plant that grows on another plant, but doesn’t insert itself into it. Just grows on top of it.

Terrestrial is when a plants grows in the ground or soil.

Floret

Individual, usually small, flowers in Asteraceae and Poaceae.

Involucral Bracts/Phyllary

One or more series of bracts immediately surrounding a flowers cluster(s).

Pappus

Modified calyx. Types: Scale, Bristle, Plumose, and Capillary.

Pollen Sacs (Pollinia)

A mass of waxy pollen, as in orchids.

Ray Flowers

A flower with a strap=like corolla.

Disk Flowers

A flower with a tubular corolla.

Receptive

Fertile = split stigma

Not Receptive

Sterile = unsplit stigma.

Resupinate

Inverted, reversed, or appearing upside down.

Viscid

Sticky.

Tuber

A thick, underground storage system.

Corms

A solid, more or less globular, underground stem.

Formic Acid

In Urticaceae, stinging hairs cause the stinging sensation.

Calcareous soil

Substrate with limestone or marble rock base = Calcium-rich soils

Mafic Soil

Substrate with silicate or igneous rock base = Magnesium & Iron Rich soils

Winter Annual

Specific type of Biennial Plant. They germinate in late summer or autumn, survives through cold winter months as a small plant, and then matures, produces flowers and seeds, and dies during the following spring or summer.

Awn

Hair point on pappus.

Closed/Fused vs Not Closed/Unfused Sheathing Leaves

Closed/Fused Sheathing Leaves: Look at the tube surrounding the stem; there is no split. You cannot pull the edges apart without tearing the tissue.

Not Closed/Unfused Sheathing Leaves: the edges usually overlap or sit against one another, but they feature a vertical split. You can easily peel or separate the edges away from the stem without ripping the tissue.

Culm

The flowering stem of grasses and sedges.

Glume

One of the two sterile bracts at the base of a grass spikelet.

Lateral vs terminal inflorescences

A terminal inflorescence forms directly at the tip of the main stem or branch, while a lateral inflorescnce forms along the sides of the stem in the axils of leaves.inflorescence

Lemma

The lower of the two bracts immediately enclosing the grass flower.

Ligule

A tongue-like appendage at the juncture of the leaf sheath and blade in Cyperaceae and Poaceae; the limb of the corolla of a ray flower in Asteraceae.

Perigynium

The membranous or papery sack-like structure that envelopes the achene in the sedge Genus Carex.

Plumose

Resembling a feather, a central axis bearing fine hairs or side branches.

Solid stems

A plant stem that is filled with tissue through its center, rather than being hollow.

Spikelets

The basic unit of the inflorescence of grasses and sedges, composed of reduced flowers and their subtending bracts.

Tristichous

Leaves arranged in three vertical rows or ranks.

Sedges have edges, rushes are round, grasses have knees that bend to the ground.

Cyperaceae = Triangular cross-section, Juncaceae = Round, smooth stems, and Poaceae = have hollow stems and swollen nodes.

Palea

The uppermost of the two bracts immediately enclosing the grass flower.

Aril

A fleshy stem structure is part of the Taxaceae family.

Cone (Male/Female) what are the differences between male and female cones

Evergreen vs deciduous

Integument

Pollen Tube

Resin