Phylum Anthopyta-The Flowering P

Phylum Anthopyta-The Flowering Plants: Key Terms and Concepts

Angiosperms- “enclosed seed”

Flower Structure

Androecium-male portion of the plant that consists of stamens, filaments, and anthers. It is responsible for the production of male gametes.

Anther-the part of the stamen the holds and produces pollen.

Calyx- the collection of sepals on a flower.

Carpel- an ovule bearing structure in angiosperms.

Corolla- The collection of petals on a flower.

Gynoecium- female portion that consists of carpels, ovary, style, and stigma. Responsible for the production of female gametes.

Peduncle-the flower stem.

Perinath-the calyx and the corolla.

Petals- whorls of structures located inside and usually above the sepals.

Pigmented petals= insected pollination

Absent petals= wind pollination.

Pistil- a single or group of carpels.

Receptacle- the portion to the flower stem that bears the floral organs

Sepals-lowermost or outermost whorls of structures, leaflike. Responsible for protection of developing flower.

Stamen-(sporophyll) filament and anther responsible for pollen production.

Stigma- apical portion (tip) of the pistil which receives the pollen grains and on which they germinate.

Style- enlogated portion of the pistil bearing the stigma.

Microsporogenesis-male

Generative Nucleus- replicates to produce 2 sperm nuclei. Found in the nucleus of a pollen grain.

Pollen Grains-microgametophytes formed from the growth and maturation of microspores.

Microsporogenesis- the production of microspores within the microsporangia via meiosis of the microspore mother cells located in the anthers. Results in the production of multiple pollen grains.

Microsporocytes (2N)->meiosis-> Microspores (N)-> mitosis-> Formation of Generative nucleus and Tube Nucleus= mature pollen grain.

Tube Nucleus- controls growth of the pollen tube. Found in the nucleus of a pollen grain.

Megasporogenesis-female

Antipodal cells-any of three haploid cells in most angiosperms that are grouped at the end of the embryo sac farthest from the micropyle.

Embryo sac- the ovule and its protective tissues.

Megasporogenesis- the production of megaspores in the sporangia of the flower ovary by meiosis of the megaspore mother cells. Results in the production of a single egg (ovule).

Megasporocyte (2N)-> meiosis-> 4 Megaspores (N)-> 3 of the nuclei degenerate-> 1 < Megaspore (egg).

Ovule- the haploid (n) megagametophyte (egg) and surrounding integument tissues.

Synergid cells- one of two small cells lying near the micropyle of the embryo sac of an angiosperm

Pollination and Fertilization

Double Fertilization- fertilization characteristic of angiosperms in which one sperm nucleus fuses with the egg nucleus to form an embryo (2N) and another fuses with polar nuclei to form endosperm (3N).

Fertilization- the process of union of two gametes. In angiosperms it refers to the union of the sperm from the pollen grain to the egg in the ovule.

Pollination- the transfer of pollen from the anther (male) to the stigma (female).

Seed and Embryo Development

Coleoptile- the first leaf of a monocotyledon that forms a protective sheath.

Coleorhiza- a protective sheath from which the roots will emerge.

Cotyledons (scutellum)- seed leaves responsible for the storage of nutrients.

Monocots- have one cotyledon per embryo

Dicots- have two cotyledons per embryo.

Endosperm- a nutritive tissue formed within the embryo sac. Provides food for the embryo.

Embryo- the young sporophyte of an angiosperm.

Hilum- an adjacent, eliptical area at which the ovule was attached to the ovary.

Meristem- tissue made up of small cells capable of dividing indefinitely to produce definitive tissues and organs

Stem apical meristem-meristem responsible for increased shoot length.

Root apical meristem-meristem responsible for increased root length.

Micropyle- a small opening on the surface of the seed through which the pollen tube grew.

Plumule- primary bud of an embryonic plant.

Radicle- embryonic root of a seedling.

Seed- a fertilized ovule.

Fruit-a mature, ripened ovary plus associated tissues.

Endocarp- the inner layer of the pericarp

Exocarp- the outermost layer of the pericarp.

Pericarp- the ripened and variously modified walls of a plant ovary

Mesocarp- middle layer of the pericarp.

Be sure you can identify the different types of fruits (ie: pomes, aggregates, berries, and legumes).