Botany Flashcards: Leaves, Twigs, Buds, and Flowers

=== Lab 1 - Leaves ===

Odd pinnately compound

Leaflets along both sides of a central axis with a single terminal leaflet at the end.

Even pinnately compound

Similar, but with no terminal leaflet; leaflets are paired to the tip.

Palmately compound

All leaflets attach at a single point at the end of the petiole.

Palmately lobed

Lobes spread from a central point (e.g., maple).

Pinnately lobed

Lobes arranged along both sides of a midrib (e.g., oak).

Opposite

Two leaves per node, opposite each other.

Alternate

One leaf per node, alternating sides.

Whorled

Three or more leaves at a node.

Petiole

Stalk connecting leaf blade to stem.

Sinuses

Spaces or indentations between lobes.

Lobes

Rounded or pointed projections on a leaf edge.

Palmate venation

Main veins radiate from a single point.

Pinnate venation

Single midvein with smaller side veins.

Serrate

Saw-toothed edge, teeth point forward.

Entire

Smooth, unbroken edge.

Sinuate

Gently wavy edge.

Double serrate

Large teeth with smaller teeth on them.

Cordate

Heart-shaped, notched base.

Ovate

Egg-shaped, broader at base.

Lanceolate

Long and narrow, widest below middle.

Obovate

Reverse of ovate; widest near tip.

Cuneate

Wedge-shaped, tapering to petiole.

Truncate

Flat or squared-off base.

Rounded

Smoothly curved base.

=== Lab 2 - Twigs, Buds, and Modified Leaves ===

Leaf scar

Mark where a leaf was attached.

Vascular scar

Small dots/lines in leaf scar showing vein connections.

Terminal bud

Bud at the tip of a twig for upward growth.

Lateral bud

Bud on the side of a twig at a node.

Pseudoterminal bud

Lateral bud taking over terminal bud's role.

Bud scale scar

Ring mark left by protective bud scales from prior year.

Imbricate

Overlapping bud scales like roof shingles.

Valvate

Bud scales meet edge to edge without overlap.

Naked buds

Buds without protective scales, only hairs or bare tissue.

Thorns

Sharp, woody modified stems.

Prickles

Sharp outgrowths of epidermis (e.g., rose).

Spines

Sharp modified leaves or parts of leaves.

Node

Point where leaves or buds attach.

Internode

Stem section between two nodes.

Short shoots

Very short twigs with closely spaced nodes.

Collateral buds

Two or more buds side by side at a node.

Superposed buds

One bud directly above another at same node.

Infrapetiolar buds

Buds hidden beneath the base of a petiole.

=== Lab 3 - Flowers ===

Sepals / Calyx

Outermost whorl, green, protective in bud stage.

Petals / Corolla

Colorful whorl inside sepals, attracts pollinators.

Pedicel

Stalk supporting a single flower.

Perianth

Collective term for calyx and corolla.

Connation

Fusion of similar floral parts (e.g., petals to petals).

Adnation

Fusion of different floral parts (e.g., stamens to petals).

Stamens

Male reproductive organs of a flower.

Anthers

Produce pollen.

Filament

Stalk supporting the anther.

Pistil

Female reproductive organ(s).

Stigma

Sticky surface that receives pollen.

Style

Stalk connecting stigma to ovary.

Ovary

Contains ovules that develop into seeds.