In an angiosperm, the terminal pollen sac of a stamen, where pollen grains containing sperm-producing male gametophytes form.
A member of one of three clades of early-diverging lineages of flowering plants. Examples are Amborella, water lilies, and star anise and its relatives.
The ovule-producing reproductive organ of a flower, consisting of the stigma, style, and ovary.
A mechanism of fertilization in angiosperms in which two sperm cells unite with two cells in the female gametophyte (embryo sac) to form the zygote and endosperm.
The female gametophyte of angiosperms, formed from the growth and division of the megaspore into a multicellular structure that typically has eight haploid nuclei.
In angiosperms, a nutrient-rich tissue formed by the union of a sperm with two polar nuclei during double fertilization. The endosperm provides nourishment to the developing embryo in angiosperm seeds.
A mature ovary of a flower. The fruit protects dormant seeds and often aids in their dispersal.
Layer of sporophyte tissue that contributes to the structure of an ovule of a seed plant.
Member of the angiosperm clade that is most closely related to the combined eudicot and monocot clades. Extant examples are magnolias, laurels, and black pepper plants.
A pore in the integuments of an ovule.
Member of a clade consisting of flowering plants that have one embryonic seed leaf, or cotyledon.
In flowers, the portion of a carpel in which the egg-containing ovules develop.
A structure that develops within the ovary of a seed plant and contains the female gametophyte.
A modified leaf of a flowering plant. Petals are the often colorful parts of a flower that advertise it to insects and other pollinators.
In seed plants, a structure consisting of the male gametophyte enclosed within a pollen wall.
The transfer of pollen to the part of a seed plant containing the ovules, a process required for fertilization.
A modified leaf in angiosperms that helps enclose and protect a flower bud before it opens.
The pollen-producing reproductive organ of a flower, consisting of an anther and a filament.
The sticky part of a flower's carpel, which receives pollen grains.
The stalk of a flower's carpel, with the ovary at the base and the stigma at the top.