Plant Diversity and Reproduction


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A Powerpoint intended for the South African Grade 11 Life Sciences syllabus. Contains information on plant classification, diversity, reproduction, the plant 'life cycle' and more.

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Plant Diversity and Reproduction

  1. 1. Module Three: Diversity, Change and Continuity Paper One
  2. 2. Simple green algaeVascular Plants Nonvascular Plants Seedless Seed-bearingCone-bearing Flowering Plants
  3. 3. Type of Vascular True leaves Need Seeds or Cones or Fruit Plant tissue and roots water to spores flowers reproduceBryophytes No No Yes Spores No NoPterophytes Yes Yes Yes Spores No No Cone- Yes Yes No Seeds Cones No bearing plants Flowering Yes Yes No Seeds Yes Yes plants
  4. 4. • Includes mosses, liverworts and hornworts• Have no vascular tissues – they have to absorb food and water through entire surface• Have no true roots, stems or leaves – They instead have rhizoids, fine outgrowths of the ‘stem’ to anchor the plant• No strengthening tissues such as xylem, therefore cannot grow tall• Are homosporous, i.e. haploid spores are all the same size• Depend on water for fertilization. The motile (flagellated) sperm depends on water to swim to the egg for fertilization
  5. 5. Are adapted for terrestrial life as they have adaptations that:• Aid nourishment – Roots absorb water and mineral salts, anchor plant and store food – Vascular tissue conduct water, glucose and minerals around plant – Supporting tissues• Aid reproduction – Have spores or seeds• Prevent desiccation – Cuticles and stomataAlso:• Sporophyte is the dominant generation• Divided into seedless and seed-bearing vascular plants
  6. 6. • Have roots, stems and leaves – Leaves, fronds, are deeply divided and are coiled in the bud• Have vascular tissue• Have a thin cuticle and stomata• Produce motile male gametes (sperm), reliant on water for reproduction. Therefore, pterophytes often live in moist areas• Have an independent sporophyte.• No flowers, seeds or cones.• New leaves are coiled up• Sporangia on undersurface of leaves• Proper roots and waxy cuticle enable them to live in dryer areas
  7. 7. • Have stems, roots and leaves• Have vascular tissue• Do not depend on water for fertilization• Are heterosporous, unlike mosses and ferns.• Produce pollen grains and resistant seeds.• Are divided into: – Cone-bearing plants – Flowering plants
  8. 8. • Are mostly trees with needle-like or strap-like leaves• Has open spore-bearing leaves (sporophylls) arranged into male and female cones.• Are heterosporous because: – The male cones produce microspores, which develop into pollen grains – Female cones produce megaspores, which develop into an ovule• After fertilization the ovule develops into an exposed seed on the female cone. It is ‘naked’ as it is not enclosed by a protective ovary wall.• Include conifers, welwitshia, cycads and ginkgo
  9. 9. • Most advanced plant, with: – Fruit – Flowers• Flowers include: – Monocotyledons – Dicotyledons
  10. 10. • Fertilization of the female gamete takes place within the ovule.• The ovary matures and contains the seeds.• The seeds are thus protected by the ovary wall, as opposed to the naked gymnosperms.• This is called the fruit.• The fruit serves as a means of seed dispersal
  11. 11. • Consists of a series of modified leaves arranged in 4 whorls: – The calyx (often green) – The corolla (often coloured) – Stamens (male whorl) – Carpels(female whorl)• The calyx and corolla are together called the perianth.
  12. 12. • Attract pollinators. – Avoid self-pollination – Not a wasteful means of production• Contain male and female reproductive organs.