AP Biology Domain Eubacteria Domain Archaea Domain Eukarya Common ancestor Kingdom: Plants Domain Eukarya

AP Biology Evolution of Land Plants  500 mya land plants evolved  special adaptations for life on dry land  protection from drying = desiccation  waxy cuticle  gas exchange (through cuticle)  stomates  water & nutrient conducting systems  from roots/soil to leaves  xylem & phloem  protection for embryo  seeds

AP Biology Plant Diversity Bryophytes non-vascular land plants Pteridophytes seedless vascular plants Gymnosperm pollen & “naked” seeds Angiosperm flowers & fruit pollen & seeds vascular system = water conduction mossesferns conifers flowering plants colonization of land Tracheophytes xylem cells = tracheids Ancestral Protist flowers monocot 1 seed leaf dicot 2 seed leaves

AP Biology Animal vs. Plant life cycle diploid multicellular individual 2n diploid multicellular sporophyte 2n haploid multicellular gametophyte 1n haploid unicellular gametes 1n gametes 1n AnimalPlant alternation of generations meiosis fertilization mitosis fertilization mitosis no multicellular haploid meiosis spores 1n zygote 2n

AP Biology diploidhaploid Bryophytes: 1 st land plants Where must mosses live?  Bryophytes: mosses & liverworts  vascular system?  No! non-vascular  no water transport system  no true roots  dominant stage?  haploid gametophyte stage  reduced, dependent sporophyte  fuzzy moss plant you are familiar with is haploid  reproduction?  swimming sperm  flagellated  spores  sprout to form gametophyte

AP Biology Bryophytes: mosses & liverworts

AP Biology Pteridophytes: 1 st vascular plants diploid haploid  Pteridophytes: ferns  vascular system?  Yes! vascular  water transport system  xylem, phloem, roots, leaves  dominant stage?  diploid sporophyte stage  fragile, independent gametophyte (prothallus)  reproduction?  swimming sperm  flagellated  spores  sprout to form gametophyte Where must ferns live?

AP Biology Pteridophytes: Ferns SelaginellaPsilotum HorsetailsFerns

AP Biology  Gymnosperm: conifers  vascular system?  Yes! vascular  xylem, phloem, roots, leaves  dominant stage?  diploid sporophyte stage  reduced (microscopic) gametophyte  reduction of gametophyte protects delicate egg & embryo in protective sporophyte  protected from drought & UV radiation  heterospory: male vs. female gametophytes  reproduction?  seeds  naked seeds (no fruit)  pollen  contain male gametophyte First seed plants: Gymnosperm Where can conifers live?

AP Biology Early Gymnosperm: ginkgo

AP Biology Early Gymnosperm: cycads

AP Biology Gymnosperm: conifers

AP Biology Cones & naked seeds

AP Biology male female male (pollen) cones female cones sporangium & pollen pine embryo

AP Biology First flowering plants  Angiosperm: flowering plants  vascular system?  Yes! vascular  dominant stage?  diploid sporophyte stage  reduced (microscopic) gametophyte  protects egg & embryo  heterospory: male vs. female gametophytes  reproduction?  flower ◆ sexual selection: attract pollinators  seeds inside fruit ◆ sexual selection: attract seed spreaders  pollen  contain male gametophyte

AP Biology Angiosperm: flowering plants

AP Biology pollen grains new sporophyte in seed (diploid) ovary sac 3n endosperm 2n zygote double fertilization female gametophyte = ovary sac (haploid) male gametophyte = pollen grain (haploid) sperm nuclei travel down pollen tube 2n embryo polar nuclei egg cell Angiosperm life cycle

AP Biology Anther Filament Stamen Stigma Style Ovary Carpel Sepal Petal Ovule sepals petals Flower  Modified shoot with 4 rings of modified leaves  sepals  petals  stamens  male  carpel / pistil  female stamens carpel adaptations through mutations

AP Biology Co-evolution: flowers & pollinators How a bee sees a flower…insects see UV light = a bulls-eye to the nectar

AP Biology Angiosperm: fruiting plants

AP Biology Other fruits…

AP Biology Seed & Plant embryo  Seed offers…  protection for embryo  stored nutrients for growth of embryo seed coat endosperm (3n) cotyledons embryo (2n) cotyledons = “seed” leaves, first leaves of new plant cotyledons = “seed” leaves, first leaves of new plant

AP Biology Monocots & dicots  Angiosperm are divide into 2 classes  dicots (eudicot)  2 cotyledons (seed leaves)  leaves with network of veins  woody plants, trees, shrubs, beans  monocots  1 cotyledon  leaves with parallel veins  grasses, palms, lilies

AP Biology