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Kingdom Plantae. Plant Characteristics. Eukaryotic Multicellular Cell walls made of cellulose Develop from multicellular embryos Carry out photosynthesis Contain chlorophyll a & b Reproduce by alternation of generations. Plant Adaptations to Land. Solutions:
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Plant Characteristics • Eukaryotic • Multicellular • Cell walls made of cellulose • Develop from multicellular embryos • Carry out photosynthesis • Contain chlorophyll a & b • Reproduce by alternation of generations
Plant Adaptations to Land Solutions: • Roots absorb H2O & minerals • Lignin & cellulose in cell walls • VascularTransport System • Waxy cuticle & stomatawith guard cells • Pollencontaining sperm Problems: • Need minerals • Gravity • Increase in Height for Light • Adaptations for Drier environment • Reproduction
Plant Evolution • First plants evolved from organisms similar to today’s multicellular green algae.(from kingdom protista)
Bryophytes • Life cycle that depends on water so the sperm can swim to the egg. • Lack vascular tissue, so they obtain water through osmosis (this limits their height) • Includes mosses, liverworts, & hornworts
Tracheophytes: seedless vascular plants • Includes club mosses, horsetails and ferns • Tracheid: new cell type that specializes in water transport. -Hollow cells with thick walls that resist pressure. • Xylem: primary fluid transport • Phloem: transport nutrients and carbs
Tracheophytes • Seedless vascular plants • Contain xylem & phloem (vascular tissue) • Xylem – carries water up from the roots • Phloem– transports products of photosynthesis
Tracheophytes • Have roots, stems, and leaves with veins • Include club mosses, horsetails, and ferns. • Ferns have rhizomes & fronds with sori • Rhizomes – fern stems • Fronds – fern leaves • Sori – fern spores
Spermatophytes • Seed Plants • Have adaptations that allow them to reproduce without water • Flowers or cones • Transfer of sperm by pollination • Protection of embryos in seeds • Two types: • Gymnosperms • Angiosperms
Gymnosperms • Bear their seeds directly on the surface of cones • Means “naked seeds” • Include conifers, ginkgo, cycads, and gnetophytes
Angiosperms • Flowering plants • Bear seeds within ovaries which surround and protect the seed. • Two types: • Monocot • Dicot
Monocots • All monocots have the following characteristics: • Single cotyledon – seed leaf • Parallel veins • Flower petals in multiples of 3 • Vascular tissue scattered throughout the stem • Fibrous roots
Dicots • All dicots have the following characteristics: • Double cotyledon seeds • Branched veins • Flower petals in multiples of 4 or 5 • Vascular tissue arranged in a ring • Taproot
Angiosperm Life Spans • Annuals – complete life cycle in one growing season • Biennials – complete life cycle in two years • First year: grow roots, short stems and sometimes leaves • Second year: grow new stems, leaves, produce flowers and seeds • Perennials – live many years
Plant Structure • Flower • Male reproductive structures - Stamen • Female reproductive structures - Carpal
Root Function • Anchor plant to the ground • Absorb water and dissolved nutrients from the soil • Water – through root pressure • Nutrients – through active transport
Types of Roots Fibrous: root formed in bundles where it is not possible to determine the primary root.Cauline: roots that shoot from the stem.Tubercular: root in the form of a tubercle.Taproot: root that grows vertically into the earth.
Plant Growth • Most plants grow and produce new cells at the tips of their roots and stems for as long as they live. • Meristematic tissue – cluster of tissue responsible for continuing growth throughout the plant’s lifetime.