Ch 22- Plant Diversity

1. Ch 22- Plant Diversity • What is a plant? • Multicellular eukaryotes, have cell walls made of cellulose • Carry out photosynthesis using pigments-chlorophyll a and b • Welcome to Discovery Education Player • Plant Life Cycle • Sporophyte- diploid phase produces spores • Gametophyte- haploid phase produces gametes • What do plants need to survive? • Sunlight, water and minerals, gas exchange, and transport of water and nutrients

3. First plants evolved from organism similar to modern multicellular green algae • 4 groups in plant kingdom based on water-conducting tissues, seeds and flowers • Mosses and their relatives • Ferns and their relatives • Cone-bearing plants • Flowering plants

5. Sec 2- Bryophytes • Bryophytes- nonvascular plant • Depend on water for reproduction • Mosses • What adaptations of bryophytes enable them to live on land? • Can draw up water by osmosis a few cm above ground • Three main groups of bryophytes • Mosses, liverworts, and hornworts

7. 3 phyla of non-vascular called Bryophytes • Mosses belong to Phylum Bryophyta • Others include liverworts and hornworts • Characteristics include • Usually grow on land near streams and rivers • Most primitive type of plant and abundant in polar regions • Closely related to algae and most terrestrial • Need water to reproduce sexually • Contain rhizoids-false roots-root like structure that anchors moss and absorbs nutrients • Life cycle of bryophytes • Gametophyte is dominant stage • Antheridia- male reproductive structure • Archegonia- female reproductive structure

9. Sec 3- Seedless Vascular Plants • Vascular tissue- type of tissue that transports water and dissolved substances from roots to leaves • Types include xylem and phloem • Xylem transports water made up of tracheids- hollow cells with thick cell walls that resist pressure • Phloem transports organic compounds • Can move fluids against gravity • Seedless vascular plants- club mosses, horsetails, and ferns • Ferns have underground stems called rhizomes and fronds which are large leaves • What are the characteristics of three phyla of seedless vascular plants? • Roots, leaves, veins, stems • Roots- underground organs that absorb water and minerals • Leaves- photosynthetic organs, contain one or more bundles of vascular tissue • Veins- vascular tissue in leaves made of xylem and phloem • Stems- supporting structures, connect roots and leaves, carry water and nutrients

14. Life Cycle of Ferns • Diploid sporophyte is dominant stage in ferns and other vascular plants • Sporangia- structure in ferns that contains spores, diploid • Sori- cluster of sporangia on underside of a fern frond

17. Sec 4- Seed Plants • Gymnosperms- seed plants that bear seeds directly on surface of cones • Gymnosperm means “naked seed” • Conifers such as pines and spruces, cycads, ancient ginkgoes • Angiosperms- flowering plants that bear their seeds within layer of tissue that protects seed • What adaptations allow seed plants to reproduce without standing water? • Flowers or cones- allow transfer of sperm by pollination and protection of embryos in seeds

18. Cones- seed bearing structure • Flowers- seed bearing structure of angiosperm • Pollen grain- male gametophyte in seed plants • Pollination- transfer of pollen from male reproductive structure to female reproductive structure • Seed- embryo of living plant that is encased in protective covering • Embryo- organism in its early stage of development • Seed coat- structure that surrounds and protects a plant embryo and keeps it from drying out • What are the four groups of gymnosperms? • Gnetophytes, cycads, ginkgoes, and conifers • All reproduce with seeds • Conifers- most common • Includes pines, cedars, spruces, redwoods, sequoias, junipers

19. Sec 5- Angiosperms • Angiosperms- members of phylum Anthophyta, originated on land • What are the characteristics of angiosperms? • Flowers- reproductive organs • Flowers contain ovaries- surround and protect the seeds • Fruit- wall of tissue surrounding the seed

20. Diversity of Angiosperms • What are monocots and dicots? • Named for # of seed leaves, or cotyledon- first leaf or first pair of leaves produced by embryo of seed plant • Monocots- single cotyledon, parallel veins, flowers in multiples of 3’s, vascular bundles scattered throughout stem, fibrous roots • Corn, wheat, lilies • Dicots- two cotyledon, branched veins, flowers in multiples of 4 or 5, vascular bundles in ring, taproot • Roses, tomatoes, oaks

21. Woody plants- thick cell walls • Trees, shrubs, vines • Herbaceous- smooth and nonwoody stems • Dandelions, sunflowers • What are the three categories of plant life spans? • Annuals- flowering plants that complete a life cycle within one growing season • Wheat • Biennials- flowering plants that complete life cycle in 2 yrs • Celery • Perennials- flowering plants that live for more than 2 yrs • Asparagus, palm and maple trees