1. Plant life cycles alternate between a sporophyte phase and gametophyte phase through the process of meiosis and fertilization. 2. The sporophyte phase produces spores via meiosis while the gametophyte phase produces gametes via mitosis which can fuse during fertilization. 3. Flowering plants undergo a double fertilization process within flowers where one sperm cell fertilizes the egg to form the embryo while another sperm cell fuses with polar nuclei to form endosperm.

1. KEY CONCEPTAll plants alternate between two phases in their life cycles.

2. SPOROPHYTE PHASEfertilizationmeiosisGAMETOPHYTE PHASEPlant life cycles alternate between producing spores and gametes.A two-phase life cycle is called alternation of generations. haploid phase diploid phase alternates betweenthe two

3. The spore-producing plant is the mature sporophyte.sporophyte phase is diploid begins with fertilized egg spores produced through meiosis The gamete-producing plant is the mature gametophyte. gametophyte phase is haploid

4. begins with spore

5. gametes produced through mitosissporophyte (2n)capsulespores (1n)gametophyte (1n)Life cycle phases look different among various plant groups.Nonvascular plants have a dominant gametophyte phase. moss gametophytes look like green carpet moss sporophytes shoot up as stalklike structures

6. sporophyte (2n)soriThe sporophyte is the dominant phase for seedless vascular plants. Fern spores form in sacs, sori, on underside of mature sporophytes (fronds).A fern gametophyte, or prothallus, produces sperm and eggs.gametophyte (1n))rhizoidA zygote forms on the prothallus, growing into the sporophyte. The sporophyte is the dominant phase for seed plants. pine trees are typical seed plant sporophytesfemale spores produced in female cones male spores produced in male cones male spores develop into pollen grains, the male gametophytes female spores develop into female gametophytes that produce eggs sperm from pollen travel down pollen tube toward egg fertilized egg develops into embryo ovule develops into protective pine seed

7. The sporophyte is the dominant phase for seed plants.

8. KEY CONCEPTReproduction of flowering plants takes place within flowers.

9. sepalFlowers contain reproductive organs protected by specialized leaves.Sepals and petals are modified leaves.Sepals are outermostlayer that protectsdeveloping flower

10. petalPetals can help to attract animal pollinators

11. stamenfilamentantherA stamen is the male structure of the flower.anther produces pollen grains

12. filament supports the anther stigmastylecarpelovaryThe innermost layer of a flower is the female carpel. stigma is sticky tip

13. style is tube leading from stigma to ovary

14. ovary produces female gametophyte Flowering plants can be pollinated by wind or animals.Flowering plants pollinated when pollen grains land on stigma.Wind pollinated flowers have small flowers and large amounts of pollen.

15. Animal pollinated flowers have larger flowers and less pollen. many flowering plants pollinated by animal pollinatorspollen grainspollination occurs as animal feeds from flower to flower

16. animal pollination more efficient than wind pollinationFertilization takes place within the flower.Male gametophytes, or pollen grains, are produced in the anthers. male spores produced inanthers by meiosis

17. each spore divides bymitosis to form twohaploid cells

18. two cells form asingle pollen grainpollen grain

19. One female gametophyte can form in each ovule of a flower’s ovary.four female spores produced in ovule by meiosis one spore develops into female gametophyte female gametophyte contains seven cells one cell has two nuclei, or polar nuclei one cell will develop into an egg

20. pollen tubespermstigmaPollination occurs when a pollen grain lands on a stigma. one cell from pollen grain forms pollen tube

21. other cell forms two sperm that travel down tube femalegametophyteeggspermpolar nucleiovuleFlowering plants go through the process of double fertilization.

22. endospermseed coatembryoFlowering plants go through the process of double fertilization.one sperm fertilizes the egg

23. other sperm unites with polar nuclei, forming endosperm

24. endosperm provides food supply for embryoEach ovule becomes a seed.The surrounding ovary grows into a fruit.

25. KEY CONCEPTSeeds disperse and begin to grow when conditions are favorable.

26. Animals, wind, and water can spread seeds.Seeds dispersed by animals can have nutritious fruits or fruits that cling.

27. CypselaeDouble samarasSeeds dispersed by wind can have wing- or parachute-like fruits.

28. Seeds begin to grow when environmental conditions are favorable.Seed dormancy is a state in which the embryo has stopped growing. Dormancy may end when conditions are favorable.

29. While dormant, embryo can withstand extreme conditions.Germination begins the growth of an embryo into a seedling. water causes seed to swell and crack coat

30. embryonic root, radicle, is first to emerge

31. water activates enzymes that help send sugars to embryoGermination begins the growth of an embryo into a seedling. water causes seed to swell and crack coatembryonic root, radicle, is first to emerge water activates enzymes that help send sugars to embryoembryonic shoot, plumule, emerges next Germination begins the growth of an embryo into a seedling. water causes seed to swell and crack coatembryonic root, radicle, is first to emerge water activates enzymes that help send sugars to embryoembryonic shoot, plumule, emerges next leaves emerge last Once photosynthesis begins, the plant is called a seedling.

32. KEY CONCEPTPlants can produce genetic clones of themselves through asexual reproduction.

33. Plants can reproduce asexually with stems, leaves, or roots.Asexual reproduction allows a plant to make copies of itself.Regeneration is one type of asexual reproduction.plants grow a new individual from fragment of parent occurs when piece of a stem, leaf, or root falls off parent plant