The document discusses the evolution of land plants from their origins in charophycean algae. It describes the main groups of land plants including bryophytes, pteridophytes, gymnosperms and angiosperms. Bryophytes were the first plants to adapt to land through developments like an embryo protected within female structures. Vascular plants like ferns and horsetails further adapted through structures like roots, stems, leaves and vascular tissue to transport water and nutrients. Most advanced are seed plants including conifers, cycads and flowering plants.

1. Plant Diversity I Level 1 Biological Diversity Jim Provan Campbell: Chapter 29

3. Highlights of plant evolution Simple charophyceans Complex charophyceans Mosses Liverworts Hornworts Lycophytes Ferns, horsetails, whisk ferns Gymnosperms Angiosperms

4. Ten phyla of extant plants Common name Approximate number of extant species Nonvascular plants (bryophytes) Division Bryophyta Division Hepatophyta Division Anthocerophyta Vascular plants Seedless vascular plants Division Lycophyta Division Pterophyta Seed plants Gymnosperms Division Coniferophyta Division Cycadophyta Division Gingkophyta Division Gnetophyta Angiosperms Division Anthophyta Mosses Liverworts Hornworts Lycophytes Ferns Conifers Cycads Gingko Gnetae Flowering plants 12,000 6,500 100 1,000 12,000 550 100 1 70 250,000

7. Alternation of generations

10. Alternation of generations in plants may have originated by delayed meiosis Meiosis delayed Zygotic mitosis produces multicellular sporophyte

12. Bryophytes

14. The gametophyte is the dominant generation in the life cycle of bryophytes

19. Pteridophytes

21. A sporophyte-dominant life cycle evolved in seedless vascular plants MITOSIS