Domain Eukarya – Kingdom Plantae*

Domain Eukarya – Kingdom Plantae*
 Characteristics: Multicellular, photosynthetic
(autotrophic), eukaryotic organisms
 Origins: Phylum Chlorophyta, Charophyceans (green
o Both have:
 Chlorophyll a, b, and carotene
 Thylakoid membranes stacked in grana
 Walls of cellulose
 Store carbohydrates as starch
 Cell plate that divides cytoplasm during mitosis
 Adaptations to land
o Roots: obtain water & minerals, anchorage for plant
o Stems & Leaves: obtain light & CO2
o Apical meristems:* growth producing regions at tips
of roots and stems
o Vascular Tissue: transport materials. Xylem* (dead
cells): convey water up & Phloem* (living cells):
distribute sugars down
o Lignin:* imbedded in wall for strength and support
o Cuticle: waxy layer to prevent water loss
o Stomata: pores on leaf surface, allows for gas
o Gametangia:* houses and protects gametes (2n) of a
o Sporangia:* houses and protects spores (n) of a plant
o Seed:* embryo surrounded by protective tissues
 Embryophytes:* distinguishes plants from algae,
dependent embryo attached to the plant
o Pollen:* formed from flagellated sperm
 No longer need water for fertilization
 Spread by wind, helps disperse over a wider area
 Life cycle: Alternation of Generations
o Multicellular, diploid (2n) & haploid (n) stages are
 Haploid: produce gametophyte (the gametes)
which in turn make gametangia
 Fertilization of gametes
 Diploid: produce sporophyte (the spores) which
in turn make sporangia
▫ uses meiosis so spores are haploid (may be
male, female or both), grow into
 Evolution: moved from sporophyte dependent on
gametophyte to gametophyte dependent on
o Gametophyte can reproduce asexually
Plant Major Groupings
 Bryophytes
o Nonvascular: lack lignified cells
o Waxy cuticle, flagellated sperm, apical meristems
o Bryophyta: Mosses, fuzzy with stalks
o Heptophyta: Liverworts, lobes with springs
o Anthocerophyta: Hornworts, lobes with horns
 Seedless Vascular Plants
o Psilophyta – whisk “ferns”
o Lycophyta – club moss
o Sphenophyta – horsetails
o Pterophyta – Ferns
Microphylls (large leaves)
 Sporangia (sacs on under side), cluster called sori
 Flagellated sperm
Seed Plants
o Seed: embryo packaged with a food supply within a
protective covering
o Do not require water for fertilization
o Gymnosperms:* “Naked Seeds,” seeds are not in
specialized chambers
Coniferophyta: cone-bearing trees; pines, firs
o Angiosperms:* seeds in protective chambers
Flowering plants
Life Cycles of Plant Groupings
 Mosses: dominant gametophyte
 Ferns & most plants: dominant sporophyte
 Gymnosperms: sporophyte with gametophytes in its cones
o Cones with scales make:
Megaspore (♀): give rise to ovules
Microspores (♂): give rise to pollen
o Spore develops into 3 cell gametophyte (egg/pollen)
o All happens on the scale of the cone
 Angiosperms: sporophyte with gametophytes in its flowers
o Flower makes megaspores (♀) & microspores (♂)
Mitosis makes spores (n) into egg sac and
Pollination = fertilization
Zygotes develop into seed (2n)
o Groups: Monocots* & Dicots*
 Flower Structure:
o Sepal: encloses flower
o Petal: Attract pollinators
o Stamen: Stalk /Filament
o Anther: Pollen grains develop
o Carpal: Has the stigma, style & ovary
o Stigma: Sticky, traps pollen
o Ovary: Seed develops
 Evolutionary trend in angiosperms
o # floral parts reduced
o Parts get fused
o Symmetry from radial to bilateral
o Ovary drops below petals and sepals