1. Plant Classification

2. Alternation of generations
Sporophyte (diploid)
Begins when sperm fertilizes egg (zygote)
Diploid zygote divides by mitosis to create a mature sporophyte
Meiosis produces haploid cells called spores
Haploid spores released

3. Alternation of generations
Gametophyte (haploid)
Begins with spores created by meiosis
Spore grows into gametophyte
Male gametophyte creates sperms
Female gametophyte creates eggs
Sperm & egg create diploid zygote (process repeats)

4. Group 1: Seedless, Nonvascular Plants
Live in moist environments
Liverworts
Hornworts
Mosses

5. Mosses Nonvascular, seedless Grow low to ground to retain moisture
Lack true leaves
Leaf-like structures only 1 cell thick
Rhizoids anchor into soil
Early inhabitant of new ecosystems (succession)

6. Moss Life Cycle Gametophyte phase Sporophyte phase Dominant stage
Carpet of moss growing near ground
Archegonium: produces female egg
Antheridium: produces male sperm
Sperm swims through water to fertilize egg
Sporophyte phase
Stalk grows up from the gametophyte
Sporangia houses haploid spores
Spores land and new gametophyte grows
Moss Life Cycle
See appendix B in your text book

7. . . . . . 1) Moss gametophytes grow near the ground (haploid stage)
2) Through water, sperm from the male gametophyte will swim to the female gametophyte to create a diploid zygote
3) Diploid sporophyte will grow from the gametophyte where the zygote is located
4) Sporophyte will create and release haploid spores . . . . .
sporophyte
gametophyte

8. . . . . . 5) Spores land and grow into new gametophytes
6) The process repeats . . . . .
ground
gametophyte

10. Group 2: Seedless, Vascular Plants
Vascular system allows nutrient transport to greater heights
Club mosses
Horsetails
Ferns

11. Ferns Seedless, vascular plants
Vascular: allows taller growth
Rhizoids: underground stems draw nutrients
Fronds: leaves uncurl
sporangia on underside
Sori: clusters of sporangia

12. Fern Life Cycle Sporophyte phase Gametophyte phase Dominant stage
Sporangia produces haploid spores
Spores released into air
Gametophyte phase
Spore grows into prothallus
Archegonium: produces female egg
Antheridium: produces male sperm
Sperm swims to egg
Zygote begins sporophyte stage
See appendix B in your text book

13. . . . . 1) Sporophyte creates and releases haploid spores Adult
Sporophyte (diploid)
ground

14. 2) Spores land in the soil. . . .
ground

15. 3) From the haploid spores, a prothallus (haploid gametophyte) grows in the soil
-- Rhizoids anchor
Let’s zoom in
ground

16. 4) Sperm swim through water from the antheridium to the archegonia
Let’s zoom back out

17. 5) Diploid sporophyte (fiddlehead) grows from the prothallus
-- prothallus eventually dies
ground

18. . . . . 6) Fiddlehead uncurls into fronds of ferns. 7) Cycle repeats
-- Sporangia creates spores to be released . . . .
ground

20. Group 3: Seed producing, Vascular Plants
Gymnosperms
Cycads
Ginko
Conifers
Angiosperms

21. Group 3: Seed producing, Vascular Plants
1) Seed plants don’t depend on water to reproduce
Pollen (contains sperm) combines with egg
Egg hardens into a seed
2) Nourishment and protection
Nourish: Nutrients inside seed for the embryo
Protection: Hard shell
3) Allow dispersal
Carried by wind, water, animals

22. Group 3: Seed producing, Vascular Plants
Type 1: Gymnosperms
Seeds not enclosed in a fruit
produced inside cones
Cone = reproductive structure
Male cones: produce pollen
Female cones: produce eggs and seeds

23. Group 3: Seed producing, Vascular Plants
Gymnosperm example: Conifers
Cone plants
Needle-like leaves
Common to lumber industry
Evergreen, Pine, Redwood, Cedar

24. Conifers Seed advantages Conifers: woody cone houses seeds
Don’t depend on water
Protects & nourishes embryo
Allow plants to grow in new locations
Conifers: woody cone houses seeds
Male cones: produce pollen
Female cones: produce egg
Pines, redwoods, spruce, cedar

25. Conifer Life Cycle Sporophyte phase (dominant) Cones grow on tree
Female cones
Megaspores inside archegonia (gametophyte)
Male cones
Microspores (gametophyte) released from antheridia
sticks to archegonium
Pollen tube grows from pollen
Sperm travels down pollen tube (zygote/seed created)
Sporophyte stage restarts

26. 1) Male and female seed cones grow in adult sporophytes

27. 2) Pollen grains released from the male seed cones
2) Pollen grains released from the male seed cones -- Pollen is the male gametophyte
Let’s zoom into the female seed cone

28. 3) Pollen grain sticks to the female ovule
4) Pollen tube grows from the male spore
5) Two nuclei transfer into female spore - one fertilizes the egg
6) Diploid embryo develops (sporophyte stage restarts)

29. 7) After seeds harden, the cone reopens and the seeds are released

30. 8) Seed will land
ground

31. 9) Seedling grows into (sporophyte)…the cycle repeats
ground

32. female
male

33. Group 3: Seed producing, Vascular Plants
Type 2: Angiosperms (flowering plants)
Flower = reproductive structure
Protects gamete and fertilized eggs
Seeds enclosed in a fruit
Fruit: Plant ovary
Often attract animals to disperse the seeds inside

34. Angiosperm types (flowering plants)
2 groups: Monocots and Dicots (based on seed type)
Cotyledon: embryonic leaf
Monocots: embryo with 1 seed leaf
Dicots: embryo with 2 seed leaves

35. Monocots vs. Dicots

36. Angiosperm Life Spans Three Life Span Types: Annuals Biennials
1 year: Mature…produce seeds…die
Biennials
1st year: produces short stem, low growth leaves, food reserves
2nd year: taller stem, leaves, flowers, seeds
Perennials
Live for more than 2 years

37. Flowers Reproductive structure of flowering plants Sepals
outer ring of leaves
protection
Petals
Inner ring of leaves
Brightly colored to attract pollinators
Open petals & sepals reveal male and female structures

38. Flowers Female Carpel Male Stamen Inner most part
Ovary: within the base (female gametophyte)
Style: long stalk
Stigma: sticky tip, collects pollen
Male Stamen
Surrounds carpel
Filaments: long stalks
Anther: produces pollen (male gametophyte)

39. 1) Flower matures and opens

40. 2) Microspores (male gametophytes) created in the anthers

41. In the Anthers Meiosis makes 4 microspores In each microspore
Nucleus splits in two
1 nucleus: forms pollen tube
1 nucleus: splits again to make 2 more nuclei
1 nucleus: fertilizes the egg
1 nucleus: fuses to make endosperm

42. 3) Microspores continue to develop

43. 4) Ovaries divide by meiosis to create megaspore

44. In the Ovules Meiosis makes 4 megaspores (only 1 survives)
In megaspore
Mitosis creates 8 nuclei
1 nucleus: egg cell
2 nuclei: form embryo sac
5 nuclei: disintegrate

45. Microspore lands on stigma

46. Microspores (pollen) released

47. Microspores (pollen) land on the stigma

48. Pollen tube and 2 nuclei transfer into the ovule. .

49. 5 & 6) Pollen tube grows from pollen
Two sperm nuclei follow down the pollen tube

50. 7) Double fertilization:
1 sperm nuclei fuses w/ egg (zygote created)
1 sperm nuclei fuses w/ the embryo sac (endosperm created)

51. 8) Ovule hardens to form seed

52. Fruit Production In the seed Embryo Endosperm
Surrounding ovary grows into a fruit
Fruit attracts animals to eat and spread the seeds
Fruit seeds in fox droppings

53. 9) Seed germinates…cycle repeats