Chapter 30: Plant Diversity II Flashcards
Embryo sac
The female gametophyte of angiosperms, formed from the growth and division of the megaspore into a multicellular structure that typically has eight haploid nuclei.
Seed
An adaptation of some terrestrial plants consisting of an embryo with a store of food within a protective coat.
Magnoliid
A member of the angiosperm clade that is most closely related to the combined eudicot and monocot clades.
Gymnosperm
A vascular plant that bears naked seeds, seeds not enclosed in protective chambers.
Pollination
The transfer of pollen to the part of a seed plant containing the ovules, a process required for fertilization.
Endosperm
In angiosperms, a nutrient-rich tissue formed by the union of a sperm with two polar nuclei during double fertilization. It provides nourishment to the developing embryo in angiosperm seeds.
Pollinator
An organism that spreads the pollen of an angiosperm.
Micropyle
A pore in the integuments of an ovule.
Pollen tube
Forms after germination of the pollen grain and functions in the delivery of sperm to the ovule.
Basal angiosperm
A member of one of three clades of early-diverging lineages of extant flowering plants.
Gnetophyta
The gymnosperm phylum that includes three genera: Gnetum, Ephedra, and Welwitschia.
Integument
Layer of sporophyte tissue that contributes to the structure of an ovule of a seed plant.
Cotyledon
A seed leaf of an angiosperm embryo. Some species have only one, and others two.
Coniferophyta
Largest gymnosperm phylum consisting of cone-bearing plants.
Gingkophyta
The gymnosperm phylum with only one surviving species.
Pollen grain
In seed plants, a structure consisting of the male gametophyte enclosed within a pollen wall.
Anthophyta
The phylum of angiosperms.
Seed coat
A tough outer covering of a seed, formed from the outer coat of an ovule. In a flowering plant, it encloses and protects the embryo and endosperm.
Archaefructus
Early fossil of larger flowering plant structures discovered in China in rocks that are about 125 million years old.
Double fertilization
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.
Cycadophyta
The gymnosperm phylum of 300 species that have large cones, palmlike leaves, and flagellated sperm.
Ovary
In flowers, the portion of a carpel in which the egg-containing ovules develop.
Monocot
A member of a clade consisting of flowering plants that have one embryonic seed lead, or cotyledon.
Ovule
A structure that develops within the ovary of a seed plant and contains the female gametophyte.
Eudicot
A member of a clade that contains the vast majority of flowering plants that have two embryonic seed leaves, or cotyledons.
