Chapter 29 Reading Quiz

1. Chapter 29 Reading Quiz • About how many species of plants inhabit earth today? • What are the two generations in the “alternation of generations”? • What structure made of waxes coats most land plant’s leaves? • What is the purpose of the structure in #3? • Which vascular tissue transports water & minerals?

2. 1. List the characteristics that distinguish plants from organisms in the other kingdoms. Plants: • Are multicellular photosynthetic eukaryotic autotrophs • have cell walls with cellulose • Store food as starch 

3. 2. Diagram a generalized plant life cycle indicating which generation is sporophyte/gametophyte, which individuals are haploid/diploid, where meiosis occurs and where mitosis occurs.

4. 3. Describe four major periods of plant evolution that opened new adaptive zones on land. • 475 million years ago  origin of plants from aquatic ancestors (green algae) • 400 million years ago  diversification of seedless vascular plants • 360 million years ago  origin of seed plants • 130 million years ago  beginning of the flowering plants 

6. 4. Distinguish between the categories division and phylum. • Division is the same as phylum, but in plants • For example: in plants the taxonomic order is  Kingdom Division (instead of Phylum) Class Order Family Genus Species 

7. 5. Using the classification scheme presented in the text, list the plant divisions; give the common name for each; and categorize them into nonvascular, vascular seedless and vascular seed plants. Nonvascular • Bryophyta  mosses • Hepatophyta  liverworts • Anthocerophyta  hornworts Seedless Vascular • Lycophyta  lycophytes • Sphenophyta  horsetails • Pterophyta  ferns continued…

9. #5 continued… Vascular seeds • Gymnosperms • Coniferophyta  conifers • Cycadophyta  cycads • Ginkgophyta  ginkgoes • Gnetophyta  gnetae • Angiosperms • Anthophyta  flowering plants 

10. 6. Provide evidence to defend the position that plants evolved from green algae. Homologies in: • Cell wall composition (cellulose) • Structure and pigmentation of chloroplasts • Biochemical similarity showing a genetic relationship 

11. 7. Describe three adaptations that made bryophytes’ move onto land possible. • Waxy cuticles (prevents dessication, or drying out on land) • Protection of gametes (seed coat, tough membranes) • Protection of developing embryos 

12. 8. Explain how bryophytes are still tied to water. • They still need water to reproduce – flagellated sperm swim to egg • No vascular tissue to carry water – must happen through diffusion, capillary action, and cytoplasmic streaming 

13. 9. List and distinguish among the three divisions of Bryophytes. Bryophyta  the mosses • Rhizoids grip ground • have stem & leaflike structures Hepatophyta the liverworts • Bodies divided into lobes • Can reproduce asexually from gemmae Anthocerophyta the hornworts • Sporophyte is horn-shaped • Cells have one large chloroplast • Most closely related to vascular plants 

15. 10. Diagram the life cycle of a moss including gamete production, fertilization, and spore production. • Separate male and female gametophytes with antheridia and archegonia • Sperm swims to archegonium and fertilizes egg • Diploid zygote divides by mitosis and develops into an embryonic sporophyte • Sporophyte grows from archegonium and remains attached • Top of sporophyte is sporangium where meiosis occurs and haploid spores develop – spores scatter • Spores germinate by mitotic development • Haploid protonema continue to grow and differentiate eventually forming sexually mature gametophytes, completing the life cycle 

17. 11. Compare environmental conditions faced by algae in an aquatic environment and plants in a terrestrial environment. Obvious issues: • Algae  live in water; don’t need vascular tissue or seeds • Plants  live on land where it’s dry; need seeds and vascular tissue to survive most effectively 

18. 12. Provide evidence that suggests the division Bryophyta is a phylogenetic branch separate from vascular plants. • The life cycle is different  the haploid gametophyte is the dominant generation in mosses and other bryophytes; the sporophytes are smaller and depend on the gametophyte for water and nutrients 

20. 13. Describe six adaptations of vascular plants, including modifications of the life cycle and modifications of the sporophyte that have contributed to their success on land. • Regional specialization of the plant body (roots, stems, leaves) • Structural support – lignin embedded into cellulose • Vascular system – xylem (water) and phloem (food) • Pollen – eliminated need for water to transport gametes • Seeds • Increased dominance of diploid sporophyte 

21. 14. List and distinguish among the three extant (not extinct) divisions of seedless vascular plants. Lycophyta  the club mosses and ground pines • Rhizomes and true leaves Sphenophyta  the horsetails • Live in damp locations with flagellated sperm • Are homosporous with a conspicuous sporophyte • Have free-living gametophytes Pterophyta  about 12,000 species of ferns • Dominant sporophyte, homosporous, free-living gametophyte • Water needed for fertilization 

23. 15. Distinguish between homosporous and heterosporous. • Homosporous  - produces a single type of spore - each spore develops into a plant with both sex organs • Heterosporous  - produces 2 types of spores 1. Megaspores – female with archegonia 2. Microspores – male with antheridia 

24. 16. Distinguish among spore, sporophyte, sporophyll, and sporangium. Spore – haploid cell that produces the gametophyte Sporophyte – multicellular diploid form resulting from the union of gametes; produces spores Sporophyll – where sporangia are found – leaves that are specialized for reproduction Sporangium – capsule in which meiosis occurs and haploid spores develop 

25. 17. Diagram the life cycle of a fern including spore production, gamete production and fertilization. • Spore production  in sporangium from the sporophyte • Gamete production  from the antheridium and archegonium on the gametophyte • Fertilization  egg (n) + sperm (n) becomes zygote (2n) and grows to become new sporophyte 

28. 18. Point out the major life cycle differences between mosses and ferns. • sporophyte is dominant in ferns, not in mosses • Spores are protected by sporopollenin in ferns, not mosses 

29. 19. Describe how coal is formed and during which geological period the most extensive coal beds were produced. • happened in the Carboniferous period - organic rubble of the seedless plants accumulated as peat - later it was covered by the sea and sediments, heat and pressure transformed the peat into coal The End!