Plant Taxonomy: Angiosperms: Flowers

Calyx

The lowest whorl of the flower, made up of sepals

Corolla

All of the petals

If the petals and sepals look the same, they’re called tepals

Androecium

All of the male parts, or stamens

Gynoecium

All of the female parts, or pistil/carpel(s)

Perfect flower

Has both male (anthers) and female (pistils/carpels) parts

Plants with perfect flowers are always monoecious

Imperfect flower

Has male or female parts, not both

Monoecious plants

Can have either perfect flowers, or both types of imperfect flowers on one plant

Dioecious plants

Only have imperfect flowers, with different plants holding different types of imperfect flowers

They cannot have perfect flowers and still be dioecious

Hypogynous

The corolla, calyx, and androecium originate below the gynoecium

Ovary superior

Perigynous

The corolla, calyx, and androecium are attached to a hypanthium surrounding, but not attached to, the ovary

Ovary half-inferior

Epigynous

The corolla, calyx, and androecium are attached to the top of the ovary

Ovary inferior

Hypanthium

A cup or strap of tissue the rim of which the corolla, calyx, and androecium are attached to

It usually surrounds or encloses the ovary

Adnate

Fusion of different types of flower parts

Connate

Fusion of the same flower parts

Sympetalous petals

Petals that are fused together

Polypetalous petals

Petals that are completely separate from each other

Monocarpous

One carpel on its own

Apocarpous

Multiple unfused carpels

Syncarpous

Multiple fused carpels

Apostemonous

Unfused stamens

Didynamous, tetradynamous, didymous

Epipetalous

A stamen fused to a petal

Diadelphous

9 stamens with fused filaments and one stamen basally fused

Monadelphous

All stamens with filaments fused

Syngenesious

Multiple stamens with anthers connate

Actinomorphic

Multiple lines of symmetry

Zygomorphic

One line of symmetry

Sepals

The lowest whorl on a flower

Collectively called the calyx

Petals

The second whorl on a flower

Collectively called the corolla

Tepals

Collective term for identical sepals and petals

Receptacle

Part of the stem where the floral organs are attached

Anther

Part of the stamen that produces and releases pollen

Style

Slender stalk in the pistil that connects the stigma to the ovary

Ovary

Base of the pistil that contains ovules and develops into fruit after fertilization

Stigma

The sticky tip of the pistil where pollen lands and begins germination

Filament

Stalk that supports the anther in the stamen

Perianth

Collective term for the petals and sepals of a flower