1. PLANT REPRODUCTION Chapter 43 Opener
Amorphophallus titanium, also known as "corpse flower," has rarely been coaxed to bloom in the U.S. The central projection, called a spadix, is often over six feet tall and is filled with small male and female flowers.

2. Plant Reproduction What Are the Basic Features of Plant Life Cycles?
How Is Reproduction in Seed Plants Adapted to Drier Environments?
What is the Function and Structure of the Flower?
Chapter 43 Opener
Amorphophallus titanium, also known as "corpse flower," has rarely been coaxed to bloom in the U.S. The central projection, called a spadix, is often over six feet tall and is filled with small male and female flowers.

3. Terms to Know
Haploid: having a single set of chromosomes in each cell.
Diploid: having two sets of chromosomes in each cell.
Mitosis: cell division, which produces two genetically identical cells.
Meiosis: reduction division, which produces four haploid reproductive cells.

4. Plants and Animals Plant Reproduction Animal Reproduction Life cycle
Alternation of generations
No alternation of generations
Gametes
Haploid (n) gametes
Haploid gametes
Spores
Haploid (n) spores
No spores
Gametes made by
Haploid gametophyte, by mitosis
Diploid organism, by meiosis
Spores made by
Diploid sporophyte, by meiosis

5. REPRODUCTION! 1:21 Asexual Reproduction Sexual Reproduction
involves only 1 parent
offspring genetically identical to parent
involves regular body cells
its quick
Sexual Reproduction
involves 2 parents
offspring genetic mix of both parents
involves specialized sex cells
its slow
1:21

6. Asexual Reproduction Binary fission
happens in bacteria, amoeba, some algae
one parent cell splits into 2 identical daughter cells
Budding
happens in yeast, hydra, corals
parent produces a bud
bud gets detached and develops into offspring which is identical to parent

7. 2 daughter cells are identical to parent
Binary Fission
Rod-Shaped Bacterium,
hemorrhagic E. coli
2 daughter cells are identical to parent

8. Budding

9. Asexual Reproduction contd.
Spore Formation
happens in fungi, green algae, moulds and non flowering plants (e.g. ferns)
spores are produced and each spore develops into offspring which are identical to parent
Vegetative Reproduction
does not involve seeds
some offspring can grow from cuttings (e.g. coleus), runners (e.g. strawberries), tubers (e.g. potatoes) or bulbs (e.g. tulips)… which are part of the parent plant

10. Spore Formation
Fern
Fungi

11. Vegetative Reproduction

12. Sexual Reproduction in Animals
involves specialized sex cells called gametes
the union of a male and female gamete results in the formation of a zygote that develops into a new individual

13. Sexual Reproduction in Plants
Female Parts
Male Parts
(Pistil)
pollen (male) + ovule (female) → single-celled zygote → multi-celled embryo (contained in a seed) → new individual

14. Sexual Reproduction in Plants
stamen is the male part and contains pollen
carpels or pistil is the female part and contains ovule (eggs)
pollen grains from the anther are transferred to the stigma by the process of pollination
self pollination (plant pollinates its own eggs)
cross pollination (pollen from one plant pollinates another plants eggs)

15. Pollination
flowers are designed to lure insects to help with the pollination process
also wind, animals, birds can transport pollen

16. Sexual Reproduction Summary
Male Gamete
Female Gamete
Type of Union
Result of Union
Final Result
Plants
pollen
ovule (egg)
pollination
single cell zygote
multi-cell embryo
(in seed)
Animals
sperm
egg
fertilization

17. Some Organisms do Both
most plants that produce seeds (sexual reproduction) can also reproduce asexually by things like cuttings or runners
this gives them an advantage for survival
Mosses produce asexual spores in the early part of their life cycle and then egg and sperm cells are produced in a later part of the same cycle.
sponges and hydra
mosses

18. Which is Better? It depends!
Asexual Reproduction
advantages
does not require special cells or a lot of energy
can produce offspring quickly
in a stable environment creates large, thriving population
disadvantages
limited ability to adapt
face massive die-off if environment changes
Sexual Reproduction
advantages
lots of variation within a species
able to live in a variety of environmental settings
able to adapt to changes in the environment
disadvantages
needs time & energy
produce small populations

19. Asexual Reproduction Natural “cloning.” Genetically Identical.
Fast, no mate required.
Beneficial for plants that must compete for scarce resources (Stable Environs).
Part of a single plant divides by mitosis to give rise to a new plants.
Spreading of runners (strawberries)
Production of bulbs (daffodils)
Sprouting of rhizomes (irises)

20. Sexual Reproduction
Fusion of egg and sperm cells (haploid), from meiosis, gamete formation and fertilization.
May be limited to a certain season.
Slower than asexual reproduction.
Allows genetic mixing, increasing variability in a population. Two parents give rise to genetically variable offspring. Favored in variable environments.

21. Alternate “Generations”
All plant life cycles are characterized by alternating of portions (haploid-to-diploid-to-haploid).
Multicellular diploid plants (sporophytes) and multicellular haploid plants (gametophytes) take turns producing each other during the reproductive life cycle.
Sporophyte: diploid (2n), produce haploid spores by meiosis.
Gametophyte: haploid (n), produce gametes by mitosis.

22. Life Cycle

23. Life Cycle
Diploid sporophyte (spore-forming plant) produces haploid spores by meiosis.
Spore germinates (begins to grow and develop); divides repeatedly by mitosis forming a haploid gametophyte (gamete-forming plant).
Gametophyte produces haploid sperm and eggs by mitosis (gametes are produced at different times to prevent self-fertilization).

24. Life Cycle
Sperm and egg fuse to form a diploid zygote (fertilized egg).
Zygote undergoes repeated mitosis to form a new diploid sporophyte plant.

25. Non-Flowering Plants
Mosses, ferns, and related plants have motile, swimming sperm.
Reproduction in these plants requires wet conditions, and requires having male and female parts close together.
Living conditions, plant size, and genetic mixing is limited.

26. Moss and Fern Life Cycles

27. Group 1: Seedless, Nonvascular Plants
Live in moist environments to reproduce
Grow low to ground to retain moisture (nonvascular)
Lack true leaves
Common pioneer species during succession
Gametophyte most common (dominant)
Ex: Mosses, liverworts, hornworts

28. A. How Do Mosses/Liverworts Get Water?
Nonvascular plant
Only about 2 to 5 cm tall, cling to damp soil, sheltered rocks, and the shady side of trees
Leaves have only one or two cells
Rhizoids: root-like fibers that are on the outside; take in water from surroundings
Continue on to next slide.

29. A. How Do Mosses/Liverworts Get Water?
Spores: cells that can develop into new organisms (seedless)
Close relative club mosses, horsetails, ferns, and spike mosses are VASCULAR
They grow thick and tall
Click this link to see pictures of moss and answer Question 1 on your sheet.

30. Continue on to next slide.
Life Cycle of Mosses
Asexual reproduction: a plant that needs only one type of cell to reproduce
This process uses spores
Sexual reproduction: a plant that needs two types of cells to reproduce
This process completes the cycle to allow reproduction
Continue on to next slide.

31. B. Life Cycle of Mosses
Alternation of generations: process of going from asexual reproduction to sexual reproduction
Click this link to learn more about what causes moss to grow and answer Question 2.

32. Moss Life Cycle

33. 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 zygote
4) Sporophyte will create and release haploid spores
Diploid sporophyte . . . . .
zygote
egg
egg
zygote
zygote
egg
egg
zygote
Haploid gametophytes
male
male
female
female
female
male
female
male

34. 5) Haploid spores land and grow into new gametophytes
6) The process repeats . . . . .
ground
Haploid gametophytes

35. Haploid gametophytes . . . . . sporophyte male male female female
zygote
egg
zygote
egg
egg
zygote
egg
zygote
Haploid gametophytes
male
male
female
female
female
male
female
male

36. Group 2: Seedless, Vascular Plants
Vascular system allows
Taller growth
Nutrient transportation
Live in moist environments
swimming sperm
Gametophyte stage
Male gametophyte: makes sperm
Female gametophyte: makes eggs
Sperm swims to fertilize eggs
Sporophyte stage
Spores released into air
Spores land and grow into gametophyte
Ex: Ferns, Club mosses, Horsetails

37. Continue on to next slide.
Parts of a Fern
Fronds: the front leaves of ferns
Rhizome: underground stem which ferns grow from; roots sprout from this
Continue on to next slide.

38. Life Cycle of Ferns
Reproduce by alternation of generation; just like mosses
Fern seeds are on the fronds of the ferns and scatter on the ground
Click this link to see the different types of ferns and the life cycle of a fern.

39. Fern Life Cycle

40. 1) Sporophyte creates and releases haploid spores
Adult
Sporophyte . . . .
ground

41. 2) Haploid spores land in the soil. . . .
ground

42. Fern gametophytes are called a prothallus
3) From the haploid spores, gametophyte grows in the soil
Let’s zoom in
Fern gametophytes are called a prothallus
ground

43. 4) Sperm swim through water from the male parts (antheridium) to the female parts (archegonia)…zygote created
Let’s zoom back out
zygote
egg
zygote
egg
zygote
egg

44. Fern gametophytes are called a prothallus
5) Diploid sporophyte grows from the zygote
sporophyte
Fern gametophytes are called a prothallus
ground

45. . . . . fiddlehead frond 6) Fiddle head uncurls….fronds open up
7) Cycle repeats
-- Haploid spores created and released . . .
fiddlehead
frond .
ground

46. 2) Haploid spores land in the soil. . . .
ground

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

48. 4) Sperm swim through water from the male antheridium to the female archegonia
Let’s zoom back out
zygote
egg
zygote
egg
zygote
egg

49. 5) Diploid sporophyte grows from the zygote
fiddlehead
sporophyte
ground

50. 6) Fiddlehead uncurls….fronds open up.
7) Cycle repeats . . . .
ground

51. Review Why do moss grow so low to the ground?
Which stage is the main stage of moss: sporophyte or gametophyte?
How do moss reproduce?
What is the major difference between moss and ferns?
What are the leaves of ferns called?
What is needed for moss and ferns to reproduce?
Which stage is the main stage of ferns: sporophyte or gametophyte?
What stage is created when sperm and egg fuse: sporophyte or gametophyte?
Name the gametophytes of ferns.

52. Conifer Pollination
Conifers (also non-flowering plants) have reduced gametophytes.
Male gametophyte is contained in a dry pollen grain.
Female gametophyte is a few cells inside of the structures that become the seed.

53. Conifer Pollination Conifers are wind-pollinated plants.
Chance allows some pollen to land on the scales of female cones.
Pollen germinates, grows a pollen tube into the egg to allow sperm to fertilize the egg.
Wind pollination is inefficient.

54. FIGURE 21-9 Life cycle of the pine
The pine tree is the sporophyte generation (upper left) and bears both male and female cones. Haploid female gametophytes develop within the scales of female cones and produce egg cells. Male cones produce pollen, the male gametophytes. A pollen grain, dispersed by the wind, may land on the scale of a female cone. It then grows a pollen tube that penetrates the female gametophyte and conducts sperm to the egg. The fertilized egg develops into an embryonic plant enclosed in a seed. The seed is eventually released from the cone, germinates, and grows into a sporophyte tree.

55. Pollen In-between
Showy flowers are the result of selection for more efficient pollination strategies.
Flower parts are modified leaves. Those that were brightly colored attracted insects in search of pollen.
Pollen itself is a protein- rich food for insects. Some plants offer other rewards, such as nectar.

56. Seed Plant Reproduction
43.2 How Is Reproduction in Seed Plants Adapted to Drier Environments?
Seed plants (gymnosperms and angiosperms).
Gametophytes develop within sporophytes.
Reproduction can occur in dry habitats.

57. Seed Plant Reproduction
Male gametophyte is surrounded by a protective coat called a pollen grain.
The pollen grain encloses sperm cells in a watertight packet that can be easily transported to another plant.
Egg-producing female gametophyte remains moist and protected within the sporophyte, and the pollen grain ensures that the sperm are delivered directly to the egg.

58. Seed Plant Reproduction
The fertilized egg becomes enclosed in a drought- resistant seed.
Consists of an embryonic plant and a food reserve encased within a protective outer coating.
May lie dormant up to years waiting for conditions favorable for germination and growth.

59. Seed Plant Reproduction
Non-flowering gymnosperms were the earliest seed plants.
Gymnosperms bear male and female gametophytes on separate cones.
Male cones release pollen grains that travel via wind to female cones.

60. Flowers

61. Sexual Reproduction - General
Angiosperms produce flowers
Flowers with both male and female reproductive organs are perfect flowers.
Flowers that have only male or only female reproductive organs are imperfect flowers.
Some angiosperms produce separate male and female flowers (imperfect flowers).
Monoecious plants
Dioecious plants

62. Angiosperms Sexual reproduction involves flowers and seeds.
Flowering can be controlled by hormones, genes and/or environmental factors

63. Flower Parts

64. Flower Structure
Evolution of the flower – purpose is attraction of pollinators.
A change from radial to bilateral symmetry.
Fusion or loss of whorls.
Odors and colors.
Nectar.
Oddly shaped petals
Flowers with 4 complete whorls = complete flower; flowers missing 1 or more whorls = incomplete flower.

65. Incomplete flowers
Flowers are complete if they have all parts, and perfect if they have both male and female parts.
Grass flowers: incomplete, usually imperfect (separate male and female flowers)
A tulip is complete (though the sepals are the same color as the petals) and perfect.

66. Imperfect flowers

67. Angiosperm Life Cycle

68. Gametogenesis: Male

69. Gametogenesis: Female

70. Double Fertilization

71. Flower to Fruit

73. Ovule to Seed

74. Seed Germination