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PLANt KINGDOM. CHARACTERISTICS. Eukaryotic cell Autotrophic nutrition ( photosynthesis ) Multicellular organisms . Reproduction : Asexual ( spores or fragments ) Sexual ( seeds ) Interaction : movements of growth. Classification of plants.
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CHARACTERISTICS • Eukaryoticcell • Autotrophicnutrition (photosynthesis) • Multicellularorganisms. • Reproduction: Asexual (sporesorfragments ) • Sexual (seeds) • Interaction: movements of growth.
Classification of plants • Plantswithoutseeds: • Plantswithoutflowersthat reproduce trhoughspores and live in wetenvironmenttobeableto reproduce. • Plantswithseeds: • Theyhaveflowersthatcontainthereproductiveorgans and haveseedswichpropagatebetterthanspores. Spermatophytes
EVOLUTION IN PLANTS • WITHOUT SEEDS WITH SEEDS (Spermatophyta) • MossesFernsGymnospermsAngiosperms • (bareseeds) (fruits) • Evolutionary time
Plantswithoutseeds Mosses • No tissuesororgans. • They reproduce bysporesformed in capsules. (Sporangium) • Non-vascular (no xylemorphloemtissue) • Without true roots, leavesorstems. Withrhizoids. • Thesurfacemustremainmoist
Plantswithoutseeds Ferns • Theyhaveroots, stem, undergroundstem (rhizome) and leaves (fronds) • Spores are formedontheunderside of thefrond in sorus. • Theylive in humidhabitats , theyneed a lot of watertosurvive. • Thereproductioniscomplex. Thecycleinvolvesspores and gametes!!!!
Plantswithseedsbut no fruitGYMNOSPERMS • Seeds are notenclosed in a fruit. Conifers are themostcommongymnosperms. • They are trees; theyhavethin and waterproofleaves. • Themajority are trees.Theflowers are theconesthatcontaintheirreproductivestructures. Unisexual. • Femalecones: largerthanmalecones. Central axis and sclaesarranged in a spiralshapearoundit. Eachscalecontainstwo ovules. • Malecones: smaller and grow in clusters. Thescalescontainmillions of pollengrains. • A pinetree’sseediscalledpinenut.
Plantswithbothseeds and fruits.Angiosperms • Most are deciduoustrees. Flowershavecalix and corolla. They can be unisexual orhermaphrodite. • Seedsare developedinto a fruitthat comes formthefertilisation of an ovule. • Ovules and pollengrains are produced in thestamen and carpels. • Pollinationisthetransference of thepollenfromtheanthertothestigma. • Thefertilised ovule developsinto a seedthatcontainsanembryo (withfood) and a seedcoat . Theovaryripensintothefruitthatcontainstheseeds
Plantstructure • Organs: • Roots: toanchortheplant and toabsorbwater and mineral salts • Stem: tosupportleaves, flowers and fruits. Itcontains a system of vascular vesselsthattransportsap • Xylem: fromrootstoleaves • Phloem: fromtheleavestoeverywhere • Leaves: with a waxylayer and stomata. Photosynthesis