LS1 Lecture 6: land plants part 2

  1. The primary wall is made up of __. Plants now have a secondary wall composed of __, the first vascular tissue that provided structural support. The secondary cell wall ends contain __
    cellulose; lignin; pits
  2. microphyl
    may have orignated as small stem outgrowths supported by single, unbranched strands of vascular tissue (needle-like projections)
  3. megaphyl
    branched vascular systems, may have evolved by the fusion of branched stems
  4. Seeds allow for __
    • stored moisture
    • allowed humans to go from nomadic to settling in one location
    • reduced gametophyte (becomes microscopic)
    • heterospory
    • ovules & pollen
  5. ovule
    • consists of the megasporangium that makes the megaspore
    • Image Upload 1
  6. pollen
    male gametophyte that goes to the megasporangium: pollination
  7. germination
    Pollen tube seeks out the egg. Then fertilization occurs.
  8. 3 generations in one seed
    • Image Upload 2
    • seed coat from integument (2n): 1st generation 
    • female gametophyte tissue, food supply for embryo (n): 2nd generation 
    • embryo, new sporophyte (2n): 3rd generation

    The new sporophyte will grow and consume the megasporangium.

    She calls them "grandmother, mother, granddaughter."
  9. gymnosperms
    • not enclosed in an ovary "naked seed"
    • Seeds sits on modified leaves of the cones

    examples of oldest gymnosperms: cycads & ginkos (only 1 extant species: ginko biloba)
  10. gnetophyta
    type of gymnosperm, short plants with large leaves.

    3 genera: gnetum, wetwritschia, ephedra
  11. coniferophyta
    most diverse gymnosperms

    large trees: pine, sequoia, yew, juniper, fir
  12. progymnosperm
    • extinct, has some features of gymnosperms such as heterospory and vascular tissue that leads to wood structure
    • no seeds
  13. special characteristic of gymnosperm life cycle
    temporal separation of megasporangia (ovulate cone) and microsprorangia (pollen cone)
  14. In gymnosperms, microsporangium produces microsporocytes that release __
    • pollen grains (containing male gametophytes) to the megasporangium (female)
    • Image Upload 3
  15. angiosperms
    • ovary seeds
    • have flowers
  16. sepals
    protect the developing bud
  17. petals
    modified leaves that attract pollinators
  18. stamen
    male parts of the angiosperm

    2 parts: anther & filament
  19. carpel
    female parts of the angiosperm

    Multiple carpels are called pistils.

    3 parts: stigma (where pollen sticks), style (pollen goes down pollen tube), ovary (holds ovules)
  20. angiosperm structures (figure)
    Image Upload 4
  21. fruit
    type of ovary that disperses seeds
  22. pericarp
    fruit "skin" acting as walls of the ovary that surround the seed
  23. proto-angiosperm
    ancestors of angiosperms that still has carpels, stamens, seeds, but doesn't have sepals or petals
  24. angiosperm monocot vs eudicot
    monocot: 1 cotyledon (embryonic leaves), parallel veins, scattered vascular tissue, fibrous roots, pollen grain with one opening, floral organs usually in multiples of 3

    eudicot: 2 cotyledons, netlike veins, ring-arranged vascular tissue, tap roots, pollen grain with 3 openings, floral organs usually in multiples of 4 or 5
Card Set
LS1 Lecture 6: land plants part 2
Ch. 31, 32, 33, 34