1. PLANTS!! Food, habitats, carbon dioxide taker uppers, oxygen providers What more could we ask for???

2. Kingdom: Plantae 280,000 species Ecological, industrial and medical importance Thought to evolve from green algae, 500 mya Both have chlorophyll a and b, store excess carbs, cellulose in cell walls.

3. 4 Evolutionary milestones Nonvascular plants that nourish a multicellular embryo within the body of the female plant (different from green algae) Vascular tissue specialized for transport (430 mya) Production of seeds (contains embryo and stored nutrients within a protective coat) 400mya Flower –reproductive structure 135 mya See cladogram pg 415

4. Alternation of Generations 2 multicellular individuals alternate, each produce the other 1.Sporophyte – diploid generation 2.Gametophyte – haploid generation

5. Sporophyte generation (2n) Sporophyte – production of spores by meiosis Spore – haploid reproduction cell that develops a new organism without fusing with another organism. Spores undergo mitosis and becomes a gametophyte

6. Gametophyte generation (n) Production of gametes Sperm and eggs are developed by mitosis fuse = diploid zygote Undergoes mitosis = sporophyte

7. Alternation of generations Meiosis produces haploid spores (gametophyte generation) Mitoisis occurs when Spore becomes a gametophyte Zygote becomes a sporophyte

8. Alternation of Generations In nonvascular plants – gametophyte is dominant Vascular seedless, naked seed and flowering plants – sporophyte is dominant Adaptation to life on land Gameotphyte becomes microscopic

9. Adaptations to terrestrial life Water transport and conservation – vascular tissue Protection from desiccation – waxy cuticle, stomata

10. Nonvascular Plants No means of transporting water or organic nutrients No true roots, stems or leaves, just root like… bryophyte – term for nonvascular plants Gametophyte is dominant generation, the part of the plant we see. Females produce eggs in archegonia Males produce flagellated sperm in antheridia need film of water for sperm to meet egg Characteristics limits size of bryophytes 3 phyla, hornworts, liverworts, and mosses

11. Hornworts and liverworts Hornworts – most live in moist shaded areas Can reproduce asexually by fragmentation Horns are sporophyte that grow from gametophyte Liveworts – most terrestrial, some epiphytes Thallose – with a flattened thallus Leafy – look like mosses Lobes look like liver Phizoids – extensions that anchor in soil

12. Mosses Gametophyte appear as leaflike structures Peat, true and rock mosses Prefer damp, shaded areas, can dry up and turn brown, and be revived with rain Can reproduce asexually by fragmentation Moss life cycle figure 24.9 Uses include sphagnum – ability to absorb water, used in gardening Peat – accumulated dead moss can be used as fuel and bandages.

13. Vascular plants Xylem – conducts water and minerals up from the roots Walls of cells are strengthened by lignin Phloem – conducts sucrose and other organic compounds down from point of photosynthesis Seedless vascular – homosporous (1 type) Seed plants – heterosporous (2 types, m/f), leads to evolution of pollen grain and seed

14. Seedless vascular plants Sporophyte dominant Independent gametophyte, archegonium and antheridium, still need water. Club mosses Ground pines, spike mosses and quillworts Have 1 strand of vascular tissue Rhizome – horizontal underground stem Strobili (cones) – contain sporangia

15. Seedless vascular Ferns and allies Horsetails Have rhizomes and stroboli Whisk ferns No leaves, sporangia are yellow, look like whisk broom Fern first fiddleheads that unrolls into fronds Megaphylls (more than 1 vascular strand) Dominant sporophyte produces windblown spores Life cycle figure 24.16 Uses: decorative, building material, medicinal, expel intestinal parasites

16. Seed plants Gymnosperms (naked seed) and angiosperms (flowering plants) Contain sporophyte embryo and stored food within a protective seed coat Allows survival during harsh conditions Heterosporous, 2 types of gametophytes (m/f) Pollen grains – male gametophyte Pollination – when pollen grain is brought to vicinity of female gametophyte by wind/pollinator, no water needed! Female gametophyte develops within an ovule which eventually becomes a seed

17. Gymnosperms Conifers, cycads, ginkgoes and gnetophytes Ovules and seeds are exposed, not enclosed by fruit (naked seed)

18. Conifers Conifers – evergreens, including pines, spruces, firs, cedars, redwoods…bears cones Tallest – redwood, oldest – bristlecone pine Life cycle of pine fig. 24.18 Used in construction, soft due to amount of xylem tissue, resin (turpentine) Monoecious – tree produces both pollen and seed cones

19. Cycads Tropical, subtropical Used in landscaping, resemble palms Pollen and seed cones on separate plants Pollinated by insects

20. Ginkgoes Maidenhair tree 1 species remains, Gingko biloba Dioecious – some trees produce seeds, other pollen Female seeds produce an odor, males preferred Resistant to pollution Seeds a delicacy Extracts used medically

21. Gnetophytes Lack archegonia, like angiosperms, thought to be most closely related Ephedra – shrub, ephedrine is extracted

22. Angiosperms Flowering plants Provide clothing, food, medicines Ovules are enclosed within diploid tissues Dominance of angiosperms is related to evolution of flying insects (pollination)

23. Monocots and Eudicots Cotyledon – seed leaf, contains nutrients that nourish the plant embryo Monocots – corn, tulips, poineapple, bamboo Eudicot – cactuses, strawberries, dandelions

24. The Flower Common structures in all flowers Peduncle – flower stalk Receptacle – expanded tip, contains the following: Sepals – (calyx) – protect the flower bud before opening Petals – (corolla) – differ in color, shape and size Stamens – consists of anther (produce pollen grains) and filament Carpels – stigma (sticky knob), style (stalk) and ovary (enlarged base that encloses ovule)

25. Flowering plant life cycle Megaspores – in ovule within ovary of carpel, develops into egg bearing female gametophyte embryo sac Microspore – produced in anthers, pollen grains, develop into sperm bearing male gametophytes Fruit – derived from an ovary

26. Diversificaiton Wind pollinated – usually bland Insect/bird pollinated – usually colorful Night blooming flowers – aromatic and white Fruits protect and aid in dispersal of seeds