Liverworts Mosses Hornworts Lycophytes Major lineages and life cycles of land plants Green plants: viridiplantae Green plants Embryophytes (land plants) Bryophytes Tracheophytes (vascular plants) Seed plants Green algae Ferns Gymnosperms Angiosperms
Green plants: viridiplantae life.umd.edu Green algae Green plants Embryophytes (land plants) Nitella (Characeae) algalweb.net embryo sporopollenin cuticle Coleochaete Land plants: embryophyta Embryophytes (land plants) Bryophytes Anthoceros Tracheophytes (vascular plants) tracheids Ceratadon stomata Marchantia
Vascular plants: tracheophyta Tracheophytes (vascular plants) Seed plants (Gymnosperms +Angiosperms) Polypodium pollen seeds true leaves (megaphylls) Lycopodium Seed plants: spermatophyta Seed plants Zamia Ginkgo Welwitschia Pinus Conifers Gymnosperms Gnetophytes Ginkgo Cycads Angiosperms
Gymnosperms Pinus monticola Thuja plicata Taxus brevifolia Chaw et al., 2000 Angiosperms Seed plants Gymnosperms Angiosperms triploid endosperm reduced female gametophyte bitegmic ovules carpel sieve tubes ovary ovule placenta
Monocots vs. dicots Monocot& One&cotyledon& Pollen&with&one&aperture&(monosulcate)& Floral&parts&in&mul5ples&of&three& Leaf&veina5on¶llel& Vascular&bundles&sca=ered&throughout&stem& Adven55ous&roots&only& Dicot& Two&cotyledons& Pollen&with&one&or&three&apertures&(tricolpate)& Floral&parts&in&mul5ples&of&four&or&five& Leaf&veina5on&re5culate& Vascular&bundles&arranged&in&a&ring& Primary&and&adven55ous&roots& Monocots vs. dicots Monocot& One&cotyledon& Pollen&with&one&aperture&(monosulcate)& Floral&parts&in&mul5ples&of&three& Leaf&veina5on¶llel& Vascular&bundles&sca=ered&throughout&stem& Adven55ous&roots&only& Dicot& Two&cotyledons& Pollen&with&one/three&apertures&(tricolpate)& Floral&parts&in&mul5ples&of&four&or&five& Leaf&veina5on&re5culate& Vascular&bundles&arranged&in&a&ring& Primary&and&adven55ous&roots&
Monocots vs. dicots Monocot& One&cotyledon& Pollen&with&one&aperture&(monosulcate)& Floral&parts&in&mul<ples&of&three& Leaf&veina5on¶llel& Vascular&bundles&sca=ered&throughout&stem& Adven55ous&roots&only& Dicot& Two&cotyledons& Pollen&with&one&or&three&apertures&(tricolpate)& Floral&parts&in&mul<ples&of&four&or&five& Leaf&veina5on&re5culate& Vascular&bundles&arranged&in&a&ring& Primary&and&adven55ous&roots& Monocots vs. dicots Monocot& One&cotyledon& Pollen&with&one&aperture&(monosulcate)& Floral&parts&in&mul5ples&of&three& Leaf&veina<on¶llel& Vascular&bundles&sca=ered&throughout&stem& Adven55ous&roots&only& Dicot& Two&cotyledons& Pollen&with&one&or&three&apertures&(tricolpate)& Floral&parts&in&mul5ples&of&four&or&five& Leaf&veina<on&re<culate& Vascular&bundles&arranged&in&a&ring& Primary&and&adven55ous&roots&
Monocots vs. dicots Monocot& One&cotyledon& Pollen&with&one&aperture&(monosulcate)& Floral&parts&in&mul5ples&of&three& Leaf&veina5on¶llel& Vascular&bundles&scaCered&throughout&stem& Adven55ous&roots&only& Dicot& Two&cotyledons& Pollen&with&one&or&three&apertures&(tricolpate)& Floral&parts&in&mul5ples&of&four&or&five& Leaf&veina5on&re5culate& Vascular&bundles&arranged&in&a&ring& Primary&and&adven55ous&roots& Monocots vs. dicots Monocot& One&cotyledon& Pollen&with&one&aperture&(monosulcate)& Floral&parts&in&mul5ples&of&three& Leaf&veina5on¶llel& Vascular&bundles&sca=ered&throughout&stem& Adven<<ous&roots&only& Dicot& Two&cotyledons& Pollen&with&one&or&three&apertures&(tricolpate)& Floral&parts&in&mul5ples&of&four&or&five& Leaf&veina5on&re5culate& Vascular&bundles&arranged&in&a&ring& Primary&and&adven<<ous&roots&
Angiosperm phylogeny Dicots with monosulcate pollen = paraphyletic Monocots = monophyletic Dicots with tricolpate pollen = monophyletic Eudicots (tricolpates) Angiosperm phylogeny Soltis et al., 2011 Rosids& Saxifragales& Asterids& Caryophyllales& Ranunculaceae& Monocots& Magnoliids& ANITA&grade&
Life cycles: animals vs. plants Life cycles: plants Alternation of generations cycle between haploid (1n) and diploid (2n) phase. =&fer5liza5on& http://en.wikipedia.org/wiki/alternation_of_generations
Life cycles: plants devbio.com Life cycles: plants devbio.com
Life cycles: plants Pollina5on& devbio.com Life cycles: pollination and fertilization Seed plants Gymnosperms Angiosperms triploid endosperm reduced female gametophyte bitegmic ovules carpel sieve tubes ovary ovule placenta
Life cycles: pollination and fertilization pollen grain = male gametophyte pollination pollen tube ovule ovary embryo sac = female gametophyte micropyle fertilization Life cycles: review Pollination transfer of pollen from anther to stigma (or male cone to female cone). Occurs only in seed plants. Fertilization fusion of egg and sperm to form zygote. Occurs in all sexually reproducing organisms. Zygote in embryophytes becomes embryo. Sporophyte the diploid (2n) generation in plants. Embryo becomes sporophyte. Produces spores. Spore the haploid product of meiosis. Gametophyte The haploid (1n) generation in plants. Spore becomes gametophyte. Produces gametes. Gamete the haploid cells that participate in fertilization: egg and sperm. Gametes in embryophytes are produced by mitosis.