Plant diversity

• Plant


  Multicellular, eukaryotic organism with cell walls made of cellulose and capable of autotrophic (photosynthetic) nutrition
• Kingdom Plantae


  • Organisms must be: Multicellular, Eukaryotic, Cell walls made of cellulose, Autotrophic (photosynthesis)
• Plant life cycles


  Alternation of generations with haploid gametophyte and diploid sporophyte stages
• Gametophyte


  Haploid individual that produces gametes
• Sporophyte


  Diploid individual that produces haploid spores through meiosis
• The first plants evolved from algae
• Adaptations for land


  • Ability to absorb nutrients, Prevent water loss, Disperse across dry land
• Roots


  Evolved to absorb nutrients from surroundings
• Cuticle


  Waxy, watertight covering to prevent water loss
• Plant groups


  • Nonvascular plants, Vascular plants, Nonseed plants, Seed plants
• Streptophytes are the green plants, including embryophytes (land plants)
• Seedless plant groups


  • Bryophytes (nonvascular), Lycophytes, Pterophytes (vascular)
• Bryophytes (nonvascular plants)


  • Do not have vascular tissue (veins) to transport water, Water moves by osmosis and diffusion, Limited in size
• Vascular plants


  • Developed vascular tissue (xylem and phloem) to transport water and nutrients over long distances, Able to grow tall
• Seed plant groups


  • Gymnosperms, Angiosperms
• Gymnosperms


  Conifers, plants with "naked seeds" not enclosed in fruit
• Angiosperms

  Flowering plants, with seeds enclosed in fruit
• Angiosperm classes


  • Monocots, Dicots
• Monocots vs Dicots

  • Monocots have one seed leaf (cotyledon), parallel venation, flower parts in multiples of 3; Dicots have two seed leaves, net venation, flower parts in multiples of 4 or 5, tap root system