Evolution of Seeds and Gymnosperms, Mosses and Early Vascular Plants, Angiosperms Pollination and Seed Dispersal, Plant Structure and Development

Seed

Embryo and nutrients in a protective coat.

Seed Plants

Plants with seeds, including gymnosperms and angiosperms.

Reduced Gametophyte

Gametophyte develops within sporophyte tissues.

Heterospory

Production of male and female spores in seed plants.

Ovule

Structure containing megasporangium and megaspore.

Pollen

Microspores develop into pollen grains with male gametophyte.

Pollination

Transfer of pollen to ovules for fertilization.

Fertilization

Fusion of sperm and egg within female gametophyte.

Dormancy of Seeds

Seeds can remain inactive until conditions favor germination.

Stored Food in Seeds

Seeds contain nutrients for embryo development.

Seed Dispersal

Seeds can be transported by wind or animals.

Gymnosperms

Seed plants with exposed seeds on cones.

Angiosperms

Flowering plants with seeds enclosed in fruits.

Cycadophyta

Phylum of cycads, large cones and palm-like leaves.

Gingkophyta

Phylum with one species, Ginkgo biloba.

Gnetophyta

Phylum with diverse genera, includes Ephedra.

Coniferophyta

Largest gymnosperm phylum, includes pines and spruces.

Bristlecone Pine

Slow-growing tree, can live over 5000 years.

Megasporangium

Structure producing megaspores in ovules.

Microsporangia

Structures producing microspores in pollen.

Hermaphrodites

Plants with both male and female reproductive structures.

Integument

Protective layer surrounding ovules in seed plants.

Sporophyte

Dominant generation in seed plants, diploid (2n).

Gametophyte

Reduced stage in seed plants, haploid (n).

Egg Nucleus

Nucleus of the female gametophyte's egg cell.

Sperm Nucleus

Nucleus of the male gametophyte's sperm cell.

Food Supply in Seeds

Nutrient reserves for developing embryo.

Microspores

Spores that develop into male gametophytes.

Megaspores

Spores that develop into female gametophytes.

Eukarya

Domain including all eukaryotic organisms.

Land Plants

Plants adapted to terrestrial environments.

Dinoflagellates

Single-celled organisms with flagella.

Forams

Protozoans with porous shells.

Green Algae

Photosynthetic protists related to land plants.

Ciliates

Protozoans with hair-like structures for movement.

Diatoms

Algae with silica cell walls.

Red Algae

Multicellular algae with red pigments.

Cellular Slime Molds

Fungi-like organisms that form multicellular structures.

Amoebas

Single-celled organisms that move using pseudopodia.

Trypanosomes

Parasitic protozoans causing sleeping sickness.

Euglena

Photosynthetic protists with flagella.

Animals

Multicellular organisms that consume organic material.

Leishmania

Parasitic protozoans causing leishmaniasis.

Fungi

Eukaryotic organisms that decompose organic matter.

Alternation of Generations

Life cycle alternating between haploid and diploid stages.

Gametophyte

Haploid stage producing gametes by mitosis.

Sporophyte

Diploid stage producing spores by meiosis.

Dependent Embryos

Embryos retained within female gametophyte tissue.

Multicellular Gametangia

Organs producing gametes in land plants.

Apical Meristems

Regions of growth at plant tips.

Nonvascular Plants

Plants lacking vascular tissue; includes bryophytes.

Bryophytes

Nonvascular plants including mosses, liverworts, hornworts.

Mosses

Small plants requiring water for reproduction.

Peat

Accumulated decayed plant material in wetlands.

Liverworts

Nonvascular plants with thalloid or leafy structures.

Hornworts

Plants with simple sporophytes, colonizing disturbed areas.

Seedless Vascular Plants

Plants with vascular tissue but no seeds.

Lycophytes

Club mosses and spike mosses, small herbaceous plants.

Monilophyta

Ferns and horsetails, diverse seedless vascular plants.

Sori

Clusters of sporangia on fern leaves.

Fiddlehead

Young, coiled fern leaf.

Seed

Embryo and nutrients in a protective coat.

Seed Plants

Plants that produce seeds for reproduction.

Reduced Gametophyte

Gametophyte stage is greatly reduced in seed plants.

Heterospory

Production of male and female spores in seed plants.

Ovule

Structure that protects female gametophytes and produces eggs.

Pollen

Structure that protects male gametophytes and produces sperm.

Gymnosperms

Seed plants with exposed seeds on cones.

Angiosperms

Flowering plants with seeds enclosed in fruits.

Megasporangia

Structures producing megaspores for female gametophytes.

Microsporangia

Structures producing microspores for male gametophytes.

Sporophyte

The dominant diploid stage in seed plants.

Germinating Pollen Grain

Male gametophyte that has begun to grow.

Pollen Tube

Structure that delivers sperm to the egg.

Carpel

Female reproductive structure in angiosperms.

Stamen

Male reproductive structure in angiosperms.

Anther

Part of stamen that produces pollen.

Style

Structure connecting ovary and stigma in flowers.

Filament

Stalk supporting the anther in flowers.

Ovary

Encloses ovules in angiosperms.

Embryo Sac

Female gametophyte within the ovule.

Zygote

Fertilized egg that develops into a new sporophyte.

Seed Coat

Protective layer surrounding the seed.

Food Reserves

Nutrients that nourish the developing embryo.

Sporophyte

Diploid generation producing gametophytes.

Microsporangium

Structure where microspores develop into pollen.

Microspores

Four haploid spores formed by meiosis.

Generative cell

Cell that divides to form two sperm.

Male gametophyte

Pollen grain containing sperm cells.

Nucleus of tube cell

Controls pollen tube growth towards ovule.

Megasporangium

Structure where megaspores develop in ovules.

Megaspore

Haploid spore that develops into female gametophyte.

Antipodal cells

Three cells at the opposite end of the ovule.

Polar nuclei

Two nuclei that fuse with sperm to form endosperm.

Egg

Female gamete fertilized by sperm to form zygote.

Synergids

Two cells assisting in pollen tube guidance.

Pollination

Transfer of pollen from anther to stigma.

Pollen tube

Structure delivering sperm to the ovule.

Endosperm nucleus

Triploid tissue providing nutrition to the developing zygote.

Double fertilization

One sperm fertilizes egg; another forms endosperm.