Kingdom Plantae An Evolutionary History of Plants Life on Earth: The First Forests Complete the information on the next two slides (also shown on the handout provided in class) as you view the film. From the film, list the order of development of the members of the plant kingdom. _______________________________ _______________________________ _______________________________ _______________________________ _______________________________ _______________________________ Circle the group(s) that exhibit each of the properties listed below. a. Require water for swimming gametes mosses club mosses ferns cycads conifers angiosperms b. Possess a vascular system mosses club mosses ferns cycads conifers angiosperms c. Produce spores mosses club mosses ferns cycads conifers angiosperms d. Produce seeds mosses club mosses ferns cycads conifers angiosperms Algae are the Ancestors of Plants Liverworts Ancestral green alga Origin of land plants (about 475 mya) Hornworts 1 Mosses Lycophytes (club mosses, spike mosses, quillworts) Origin of vascular plants (about 425 mya) 2 Pterophytes (ferns, horsetails, whisk ferns) Gymnosperms 3 Origin of seed plants (about 360 mya) Angiosperms 500 450 400 350 Millions of years ago (mya) 300 0 Characteristics of Plants • • • • • • • Eukaryotic Multicellular Autotrophic: photosynthetic Sexual and asexual reproduction Cell wall made of cellulose Usually non-motile except for gametes Adapted to life on land Adaptations to Life on Land • • • • • • Roots and root-like structures Conduction vessels Structural support Water-proof covering Pores for gas and water exchange Mechanisms for dispersal of reproductive products Vascular Plants Non-vascular Seed Plants Plants Liver- Mosses Ferns Gymno- Angioworts sperms sperms Evolutionary Tree of Major Plant Groups Flowers & Fruits appear True vascular tissue and lignin appear Ancestral Algae Seeds and pollen appear Shows increasing adaptations for land dwelling Plant Life Cycle: Alternation of Generations Gametes form by mitosis Gametophyte n Spores form by meiosis Spores n n n n n Sperm Gametes meet Haploid n Egg & fuse to form zygote 2n Spore Mother Cell 2n Zygote Diploid Sporophyte 2n 2n Embryo Evolutionary trend: reduction of gametophyte Bryophytes: Mosses • No fluid-conducting vascular system • Enclosed reproductive structures • Require moist environments Sporophyte (stalk) Female Gametophyte (leafy) Vascular Plants • Specialized groups of conducting cells organized into vessels • Functions of vessels – conduct water and nutrients – provide support to plant body with lignin • Largest group of plants Vascular Plants: Ferns • Seedless vascular plants • Tall leafy Sporophyte • Gametophyte requires moist environment Archegonia produce eggs Antheridia produce sperm Gametophyte Mature Sporophyte mitosis, differentiation, growth Young Sporophyte mitosis, differentiation, growth fusion to form zygote meiosis Spore Case mitosis, differentiation, growth Egg growth Zygote Mature Gametophyte Sperm Diploid 2n Haploid 1n Fern Life Cycle Vascular Plants: Gymnosperms • Seed-producing vascular plants • Pollinated by wind • Conifers adapted to cold, dry climate – cones to protect seeds – evergreen – waterproof needle-like leaves – sap does not freeze Vascular Plants: Gymnosperms Coastal Redwood (Tallest Trees) Giant Sequoia (Largest Living Thing) Two Uncommon Gymnosperms Gingko Cycad These plants have separate sexes, ie. male and female plants. Vascular Plants: Angiosperms • Seed and fruit-producing vascular plants • Broad, waterproof leaves • Modified leaves = Flower = reproductive structure • Many have animal pollinators; some use wind • Greatly reduced gametophyte (pollen grain and embryo sac with egg) • Largest number of species (250,000) Applying Your Knowledge 1. 2. 3. 4. Mosses Ferns Gymnosperms Angiosperms Which group of plants • Encloses seeds within fruit? • Does not have a vascular system? • Protects seeds within a cone? • Has a vascular system but does not produce seeds?