Kingdom Plantae

• Kingdom Plantae characteristics:

  • Eukaryotic
  • Multicellular
  • Photosynthetic
  • Cell walls contain cellulose
  • Develop from embryos protected by parental tissue
• Earliest land plants may have evolved from algal-like organisms
• Generalized life cycle of plants involves alternation of generations:

  • Gametophyte generation (n)
  • Sporophyte generation (2n)
• Plant types:

  • Non-Vascular (bryophytes)
  • Vascular (tracheophytes)
  • Non-Vascular plants include mosses, liverworts, and hornworts
• Non-Vascular plants:

  • Lack true roots, stems, leaves, and vascular tissue
  • Grow in moist environments
  • Reproduction: Sexual (spores) or asexual (vegetative propagation)
• Vascular plants have conducting tissue (xylem & phloem) allowing for greater heights
• Spore-producing vascular plants include club mosses, horsetails, and ferns
• Reproduction in non-vascular & spore-producing vascular plants requires water for sperm to fertilize egg
• Seed-producing vascular plants are the most successful on Earth, with specialized leaves, stems, and roots
• Gymnosperms:

  • Reproductive structures: pollen cones (male) and seed cones (female)
  • Pollen dispersed by wind
  • Example: Conifers
• Angiosperms:

  • Known as flowering plants
  • Most successful plants on Earth
  • Reproduction: ovum fertilized by sperm, zygote develops into an embryo contained in a seed
• Angiosperms have well-protected seeds and a variety of seed dispersal mechanisms like wind, water, or animals
• Asexual reproduction in plants can occur through vegetative reproduction methods like runners and roots
• Comparison of reproductive processes between angiosperms and gymnosperms:

  • Angiosperms: ovum fertilized by sperm, zygote develops into an embryo contained in a seed enclosed in a fruit
  • Gymnosperms: pollen cones produce sperm that fertilizes ovules, zygotes grow into seeds
• Difference between self-pollination and cross-pollination:

  • Self-pollination: pollen from the same plant fertilizes the ovum
  • Cross-pollination: pollen from one plant fertilizes the ovum of another plant