1. Origin of the Land Plants

2. Alternation of Generations

3. Charophycean Algae Don’t display alternation of generations Most closely related to land plants by homology Organisms are haploid Examples: Chara and Coleochaete Single-celled zygote produces haploid spores by meiosis Gametes are bi-flagellate

4. Homologies Between Charophyceans and Land Plants Chloroplasts have chlorophyll a & b, carotenoids and other accessory pigments Cell walls with cellulose (20-26%) Peroxisomes with anti-photorespiration enzymes Phragmoplasts for cell plate formation Rosette cellulose-synthesizing complexes Molecular systematics: DNA, rRNA, chloroplast DNA

5. Chara – Pond Algae

6. Challenges of Moving to Land Lack of moisture Ultraviolet light Separation of water, minerals, and carbon source (CO 2 ) Lack of support for the plant body Rapidly changing environmental conditions

7. Bryophytes Nonvascular plants Dominant form is the haploid gametophyte Swimming gametes require water Diploid dependent sporophyte produces haploid spores by meiosis. Spores grow into gametophyte plants that produce haploid gametes by mitosis. Mosses, liverworts, hornworts

8. Liverwort Gemmae cups of Marchantia

9. Marchantia

10. Moss Sporophyte and capsule Gametophyte plant (n)

11. Polytrichum - Moss

13. Peat Bogs Store Carbon

14. Spagnum Moss

15. VASCULAR PLANTS (TRACHEOPHYTES)

16. Branched, independent sporophytes Sporophytes are the dominant plant Asexual reproduction: Spores Sexual reproduction: Gametes Swimming gametes require water Possess Xylem and Phloem True roots, stems and leaves in some groups Pteridophytes (Seedless Vascular Plants)

17. Lycophyta: Club MossesPterophyta: Whisk Ferns Sphenophyta: Horsetails Pterophyta: Ferns

18. Lycophyta Woody trees dominating Carboniferous period (300 mya) Epiphytes – “Air Plants” Club-shaped spore-bearing cones called strobili Spores very flammable

19. Sphenophyta Woody trees during Carboniferous period Hollow ribbed stems jointed at nodes Silica (silicon dioxide) granules Equisetum hyemale or Scouring rush

20. Polypodium fern

21. Fern Life Cycle

22. Sori on lower side of frond

23. Sorus and mature sporangium

24. Fern Prothalus (Gametophyte Plant)