2. Fern Life Cycle

3. Alternation of generations Defined: Plants alternate between a diploid organism and a haploid organism

4. Alternation of generations Zygote created from egg & sperm (fertilization begins sporophyte phase)

5. Alternation of generations Zygote divides by mitosis to create adult sporophyte

6. Alternation of generations Haploid spores created by meiosis (beginning of gametophyte stage)

7. Alternation of generations Haploid spores released into air

8. Alternation of generations Female gametophyte creates eggs Male gametophyte creates sperm Spore grows into male or female gametophyte

9. Alternation of generations Sperm & egg create diploid zygote (sporophyte stage restarts)

10. Alternation of generations Cycle repeats

11. Group 2: Seedless, Vascular Plants Evolutionary Advancement: Vascular system –a–allows nutrient transport to greater heights Live in moist environments –S–Swimming sperm Structure: –R–Rhizoids = primitive roots –L–Leaves = fronds Categories: –C–Club mosses –H–Horsetails –F–Ferns water glucose

12. Sporophyte phase –Dominant stage; Diploid See appendix B in your text book Fern Life Cycle

13. Sporophyte phase –Dominant stage; Diploid –Fronds house sori (pl.) See appendix B in your text book Fiddlehead Fern Life Cycle Fiddlehead uncurling Frond

14. Sporophyte phase –Dominant stage; Diploid –Fronds house sori (pl.) Sorus (sing.) = Cluster of sporangia See appendix B in your text book Fern Life Cycle

15. Sporophyte phase –Dominant stage; Diploid –Fronds house sori (pl.) Sorus (sing.) = Cluster of sporangia Sporangia make spores Spores created by meiosis Spores released into air See appendix B in your text book Fern Life Cycle

16. Sporophyte phase –Dominant stage; Diploid –Fronds house sori (pl.) Sorus (sing.) = Cluster of sporangia Sporangia make spores Spores created by meiosis Spores released into air See appendix B in your text book Fern Life Cycle Sporangia act like catapults

17. Sporophyte phase –Dominant stage; Diploid –Fronds house sori (pl.) Sorus (sing.) = Cluster of sporangia Sporangia make spores Spores created by meiosis Spores released into air See appendix B in your text book Fern Life Cycle Sporangia act like catapults

18. Sporophyte phase –Dominant stage; Diploid –Fronds house sori (pl.) Sorus (sing.) = Cluster of sporangia Sporangia make spores Spores created by meiosis Spores released into air Gametophyte phase –Spore grows into prothallus See appendix B in your text book Fern Life Cycle

19. Sporophyte phase –Dominant stage; Diploid –Fronds house sori (pl.) Sorus (sing.) = Cluster of sporangia Sporangia make spores Spores created by meiosis Spores released into air Gametophyte phase –Spore grows into prothallus –Prothallus contains: Archegonium: produces female egg Antheridium: produces male sperm Sperm swims to fertilize the egg See appendix B in your text book Fern Life Cycle

20. Sporophyte phase –Dominant stage; Diploid –Fronds house sori (pl.) Sorus (sing.) = Cluster of sporangia Sporangia make spores Spores created by meiosis Spores released into air Gametophyte phase –Spore grows into prothallus –Prothallus contains: Archegonium: produces female egg Antheridium: produces male sperm Sperm swims to fertilize the egg Fertilization restarts sporophyte stage See appendix B in your text book

21. Adult Sporophyte (diploid).... 1)Sporophyte creates haploid spores by meiosis. Spores are released from the sori on the under-side of fronds ground

22. .. 2) Haploid spores land in the soil

23. ground 3) From the haploid spores, the prothallus (gametophyte) grows Let’s zoom in..

24. 4) Sperm swim through water from the antheridia (XY) to the archegonia (XX) Let’s zoom back out zygote

25. ground 5) Diploid sporophyte grows from the zygote on the prothallus -- prothallus eventually dies sporophyte

26. 6) Fiddlehead uncurls…fronds open up ground 7) Cycle repeats… -- Haploid spores created and released....

27. Place the steps of the fern life cycle in order, from the step started for you: __ 1 ___ Spores land on soil. _______ Sporophyte releases spores. _______ Through water, sperm swim from antheridium to archegonium on prothallus. _______ Prothallus grows. _______ Fertilization occurs. _______ Diploid sporophyte begins to grow. 2 3 4 5 6

28. Plant Life Cycle Comparisons Plant typeSporophyteGametophyteDominant? MossStalk with cup (capsule) at tip, which is where spores are produced. More familiar, carpet-like plant that produces specialized gametes GAMETOPHYTE FernMore familiar, leafy plant with clusters of spore producing sacs (sori) Haploid plant body (prothallus) is size of a finger nail, produces both male and female parts SPOROPHYTE ConiferMore familiar- like pine trees, produces male and female cones that produce spores Pollen grains are male gametophytes  sperm, female gameotphytes are microscopic  eggs SPOROPHYTE

29. Review 1)What is the major difference between moss and ferns? 2)What are the leaves of ferns called? 3)What is needed for moss and ferns to reproduce? 4)Which stage is the main stage of ferns: sporophyte or gametophyte? 5)What stage is created when sperm and egg fuse: sporophyte or gametophyte? 6)Name the gametophyte of ferns. 7)Which process begins the gametophyte stage? 8)What structure on the fern creates spores?