PLANT KINGDOM INTRODUCTION
What are Plants?
What is a plant?
Plants are derived from green algae (protists).
Most algae are aquatic protists.
Life on land presented opportunities.
Plants meet the challenges of terrestrial life in various ways.
Key adaptations in the evolution of plants.
Figure from Campbell, et.al. Biology, 10th ed. Pearson/Benjamin Cummings, NY.
Key adaptations in the evolution of plants.
Figure from Campbell, et.al. Biology, 10th ed. Pearson/Benjamin Cummings, NY.
PHYLOGENY OF THE PLANT KINGDOM
Phylogeny of the plant kingdom.
Figure from Campbell, et.al. Biology, 10th ed. Pearson/Benjamin Cummings, NY.
THE THREE LIFE CYCLES
animal (diplontic) cycle
fungus/algae (haplontic) cycle
plant (alternation of generations) cycle
Terms involving chromosomes.
Nuclear division processes, and reproductive cells.
Animal life cycle.
Animal life cycle.
Figure from Campbell, et.al. Biology, 10th ed. Pearson/Benjamin Cummings, NY.
Algae/fungus life cycle.
Plant life cycle.
Another view of the plant life cycle.
Figure from Campbell, et.al. Biology, 10th ed. Pearson/Benjamin Cummings, NY.
PLANT LIFE CYCLES IN DETAIL
bryophytes (moss example)
seedless vascular plant (fern example)
seed plant (angiosperm example)
Moss life cycle.
Figure from Campbell, et.al. Biology, 10th ed. Pearson/Benjamin Cummings, NY.
Features of bryophytes
A moss showing both gametophyte and sporophyte stages of the life cycle.
In bryophytes, the gametophyte is the dominant stage.
Liverworts are a separate “bryophyte” phylum.
Hornworts are a separate “bryophyte” phylum.
Fern life cycle.
Figure from Campbell, et.al. Biology, 10th ed. Pearson/Benjamin Cummings, NY.
Traits of ferns.
The familiar fern plant is a sporophyte.
Fern gametophyte is green, tiny, flat, and separate from the sporophyte.
The undersurface of a woodfern bears sporangia.
Flowers are aggregates of sexual organs in angiosperms.
Figure from Campbell, et.al. Biology, 10th ed. Pearson/Benjamin Cummings, NY.
Flowers are aggregates of sexual organs in angiosperms.
Pollination.
Fertilization.
A fruit is a ripened ovary containing seeds.
A peanut is a fruit.
A peanut is a fruit.
Flowering plant gametophytes are tiny.
In fact, the female gametophyte is contained completely within the sporophyte!
Double fertilization is a unique angiosperm feature that ties food (endosperm) development to the presence of an embryo in need of nourishment.