Chapter 29: Life Cycles of Flowering Plants

calyx

A flower's outer, protective whorl of sepals.

corolla

A flower's whorl of petals; forms within sepals and encloses reproductive organs.

pollinator

An animal pollination vector.

pollination vector

Animal or environmental agent that moves pollen grains from one plant to another.

double fertilization

Fertilization as it occurs in flowering plants. Two cells are fertilized: One sperm cell fuses with the egg to form the zygote; the second sperm cell fuses with the central cell to form a triploid (3n) cell that gives rise to endosperm.

stamen

Floral reproductive organ that consists of an anther and, in most species, a filament.

carpel

Floral reproductive organ that produces the female gametophyte; consists of an ovary, stigma, and usually a style.

vegetative reproduction

Growth of new roots and shoots from extensions or fragments of a parent plant; a form of asexual reproduction.

pollen grain

Immature male gametophyte of a seed plant.

ovary

In flowering plants, the enlarged base of a carpel, inside which one or more ovules form.

coleoptile

In monocots, a rigid sheath that protects the plumule (embryonic shoot).

tissue culture propagation

Laboratory method in which embryonic plants are grown from individual meristem cells.

fruit

Mature ovary of a flowering plant, often with accessory parts; encloses a seed or seeds.

seed

Mature ovule of an angiosperm. Consists of an embryo sporophyte, nutritive tissue, and a protective seed coat.

endosperm

Nutritive tissue in the seeds of flowering plants.

ovule

Of a seed plant, the part of the carpel where the female gametophyte forms.

megaspore

Of seed plants, haploid spore that forms in an ovule and gives rise to an egg-producing gametophyte.

microspore

Of seed plants, haploid spore that gives rise to a pollen grain.

anther

Part of the stamen that produces pollen grains.

dormancy

Period of temporarily suspended metabolism.

flower

Specialized reproductive structure of an angiosperm.

nectar

Sweet fluid exuded by some flowers; rewards pollinators.

pollination

The arrival of pollen on a pollen-receiving reproductive part of a seed plant.

germinate

To resume metabolic activity after dormancy.

sepal

Unit of a flower's calyx; typically photosynthetic and inconspicuous.

petal

Unit of a flower's corolla; often showy and conspicuous.

stigma

Upper part of a carpel; adapted to receive pollen.