Plant Systematics - Exam 1

Synapomorphy

shared derived trait that’s present in a group of organisms and their common ancestor

Whorled leaves

more than two leaves per node

Basal leaves

leaves that grow at the base of the plant/stem

describe the leaf shape

elliptical

describe the leaf shape

linear

describe the leaf shape

lanceolate

describe the leaf shape

ovate

describe the leaf shape

oblong

describe the leaf shape

cordate

describe the leaf apex

acuminate

describe the leaf apex

acute

describe the leaf apex

obtuse

describe the leaf margin

crenate

describe the leaf margin

denate

Indument

hairs on a plant

Stipules

paired or sheathing (wrapped around stem). Little flaps of tissue near the base of the petiole

Tendrils

modified stem or leaf used for climbing

Thorns

modified branch, come out from auxiliary buds and at the node

Spines

modified leaves or stipules, usually paired

Prickles

outgrowth of epidermis, can be anywhere on the plant

Rhizome

horizontal stem, usually underground

Bulb

compact underground stem

Tuber

thickened stem or roots, usually full of starches for storage

Liana

a woody vine

Carpel

female reproductive unit of a flower

Sepal

1st whorl: the green, leaf-like part of a flower (isn’t always green), protects developing flower

Calyx

what sepals are collectively called. All sepals on a flower

Petals

2nd whorl: brightly colored to attract pollinators

Corolla

what petals are collectively called. All petals on a flower

Perianth

term used to describe both calyx and corolla together

Stamen

3rd whorl: pollen producing structure. 2 parts: anther and filament

Androecium

what stamen are collectively called. All stamen in a flower

Pistil

4th whorl: seed producing structure, comprised of carpel(s). 

Gynoecium

what pistils are collectively called. All the pistils in a flower

Stigma

part of carpel that’s the landing pad for pollen

Style

part of carpel where the pollen tube passes down

Ovary

enlarged basal part of carpel, contains one or more ovules (which will eventually become seeds)

What is the order that pollen travels?

stigma→style→ovary

Perfect flowers

flower has both stamens and pistil(s)

Imperfect flowers

flowers that have the stamens or pistils that are highly reduced so they don’t function. Only one of the two works

Monoecious

A single plant has staminate and pistillate flowers

Diecious

Male or female plants, will only have either staminate or pistillate flowers

Connate fusion

when parts of the same whorl are fused together

Adnate fusion

when parts of adjacent whorls are fused together (stamens + petals, or pistil + stamens)

Hypanthium

fusion of sepals, petals, and stamens, can form a cup-like structure

Radially symmetrical/actinomorphic

can be cut anywhere and folded in half and be symmetrical

Bilaterally symmetrical/zygomorphic

can be cut in half in only one spot and be symmetrical

Superior ovary

ovary is above the other whorls, sepals “below” the fruit

Half-inferior ovary

ovary is in the middle of the whorls, between superior and inferior

Inferior ovary

ovary below the other whorls, sepals “above” the fruit

Inflorescence

the arrangement of flowers

Indeterminate inflorescence

oldest growth towards the base of the stem, youngest growth at the tip

Determinate inflorescence

youngest growth towards the base of the stem, oldest towards the tip

What type of inflorescence is this?

receme, flowers of pedice

Peduncle

axis that stems all the flowers

What type of inflorescence is this?

cyme, indeterminate. Central flower develops firs

What type of inflorescence is this?

spike, flowers are sessile (no pedicels)

What type of inflorescence is this?

Panicle, branched lateral axis

Sessile

flowers that lack a pedicel (a little stem)

What type of inflorescence is this?

Umbel, flat-topped, pedicels attach at one point

What type of inflorescence is this?

Corymb, pedicels attach at more than one point

Fruit

seed bearing structure derived from an ovary/ovaries

Pericarp

what the endocarp, mesocarp, and exocarps are collectively called

Simple fruit

fruits that come from one pistil (can be simple pistil or compound pistil)

Aggregate fruit

fruit that come from many simple pistils together (that are all from the same flower)

Multiple fruit

fruit that come from many flowers

Accessory fruit

aggregate or multiple fruit embedded in non-ovary tissue

Dehiscent fruits

splits open along seam to release seeds

Indehiscent fruits

fruit that doesn’t split open to release seeds

Follicle

derived from simple pistil, has one locule, splits open along one seam

Legume

derived from simple pistil, splits open along two seems

Loment

legume that breaks into one-seeded pieces

Capsule

derived from compound pistil, multiple locules, opens along joined seams

Schizocarp

one seed per locule, splits apart into one-seededunits

Locule

chamber within an ovary/fruit

Achene

single-seeded indehiscent fruit, seeds held loosely within hardened pericarp

Nut

single-seeded indehiscent fruit, seed is fused to a hardened pericarp, usually with involucer

Involucer

cup-like structure derived from bracts

Berry

has one or more seeds, has fleshy pericarp, usually has “skin” or “rind”

Drupe

has one seed that’s surrounded by a “pit” (hardened endocarp)

Marginal placentation

seeds attached along a single line along the ovary wall, fruits w/ simple pistil and one locule

Parietal placentation

seeds attached along several lines along the ovary wall, fruits w/ compound pistil and one locule

Axile placentation

seeds attached along the central column, fruits w/ compound pistil and multiple locules

Free-central placentation

seeds attached along the central column, fruits w/ compound pistil and one locule

Basal placentation

a single seed attached at the base of the ovary

Monocots

leaf venation parallel, flower parts in multiples of 3, never woody

Water lilies, magnolias, and relatives

not monophyletic, flower whorls poorly differentiated (spiraled), strong odors

Dicots

leaf venation netted, flower parts in multiples of 4 or 5

Rosids (dicots)

petals not fused, stamen # greater than petal #, stamens not fused to petals

Asterids

petals connate, stamen # equal or less than petal #, stamen adnate to petals

Bract

modified leaf in an inflorescence 

Araceae

rhizome or tuber, huge variation in size, inflorescence is a spathe and spadix, flowers tinyP(a)4-6(or 0), A 1-6, G 1-3 (g is circled and underlined)

Alismataceae

rhizomes, basal leaves, latex, inflorescence is receme or panicle, radially symmetrical, fruit aggregate of achenes. Ca3, Co(a)3, A6-infinity, G6-infinity

Juncaceae

rhizomes, rush family, leaves basal and round, inflorescence: congested cyme, flowers bisexual. P(a)6, A6, (G3) (circle and line under)

Cyperaceae

sedge family, sometimes rhizomatous, stems solid and triangular, leaves in 3 ranks and sheaths closed, often monoecious

Poaceae

grass family, stem internodes hollow, leaves in 2 ranks, sheaths open, leaves with ligules. A3, G2

Spikelet

one or more flowers and bracts

Glumes

bracts at the base of the spikelet

palea and lemma

bracts at the base of each flower