1. An overview of angiosperm reproduction
Anther
Germinated pollen grain (n)
(male gametophyte)
Anther
Stigma
Stamen
Carpel
Style
Ovary
Filament
Pollen tube
Ovary
Ovule
Embryo sac (n)
(female gametophyte)
Sepal
FERTILIZATION
Petal
Egg (n)
Sperm (n)
Receptacle
Zygote
(2n)
Mature sporophyte
plant (2n)
(a) Structure of an idealized flower
Key
Haploid (n)
Diploid (2n)
Seed
Figure 38.2 An overview of angiosperm reproduction
Germinating
seed
Seed
Embryo (2n)
(sporophyte)
(b) Simplified angiosperm life cycle
Simple fruit

2. Structure of an idealized flower
Anther
Stigma
Carpel
Stamen
Style
Filament
Ovary
Sepal
Petal
Figure 38.2 An overview of angiosperm reproduction
Receptacle
Structure of an idealized flower

3. Angiosperm Life Cycle Pollination Anther pollen Pollen tube
Germinated pollen grain (n)
(male gametophyte)
Anther
pollen
Ovary
Pollen tube
Ovule : Double Fertilization
Embryo sac (n)
(female gametophyte)
FERTILIZATION
Egg (n)
Endosperm
(3n)
Zygote
(2n)
Sperm (n)
Mature sporophyte
plant (2n)
Key
Figure 38.2 An overview of angiosperm reproduction
Seed
Haploid (n)
Diploid (2n)
Germinating
seed
Seed
Embryo (2n)
(sporophyte)
Simple fruit

4. gametophyte (in pollen grain) Development of a female
Development of a male
gametophyte (in pollen grain)
(b)
Development of a female
gametophyte (embryo sac)
Microsporangium
(pollen sac)
Megasporangium (2n)
Microsporocyte (2n)
Ovule
Megasporocyte (2n)
MEIOSIS
Integuments (2n)
Micropyle
4 microspores (n)
Surviving
megaspore (n)
Each of 4
microspores (n)
MITOSIS
Ovule
Generative cell (n)
Male
gametophyte
3 antipodal cells (n)
Figure 38.3 The development of male and female gametophytes in angiosperms
Female gametophyte
(embryo sac)
2 polar nuclei (n)
1 egg (n)
Nucleus of
tube cell (n)
Integuments (2n)
2 synergids (n)
20 µm
Ragweed
pollen
grain
Embryo
sac
75 µm
100 µm

5. Adapted for wind pollination
Abiotic Pollination by Wind
Adapted for wind pollination
Figure 38.4 Flower pollination
Hazel staminate flowers
(stamens / male sex organs only)
Hazel carpellate flower
(carpels / female sex organs only)

6. Color = visual cue / signal to attract pollinators
Pollination by Bees
Common dandelion under
normal light
Figure 38.4 Flower pollination
Common dandelion under
ultraviolet light

7. Chemical signal: Odor attracts flies
Pollination by Flies
Chemical signal: Odor attracts flies
Figure 38.4 Flower pollination
Fly egg
Blowfly on carrion flower

8. Nectar = chemical attractant
Pollination by Birds
Figure 38.4 Flower pollination
Hummingbird drinking nectar of poro flower

9. Growth of the pollen tube
and
double fertilization
Stigma
Pollen grain
Pollen tube
2 sperm
Style
Ovary
Polar nuclei
Ovule
Micropyle
Egg
Ovule
Polar nuclei
Egg
Synergid
Figure 38.5 Growth of the pollen tube and double fertilization
2 sperm
Endosperm
nucleus (3n)
(2 polar nuclei
plus sperm)
Zygote (2n)
(egg plus sperm)

10. Seed Structure 2 Cotyledons Endosperm Coleoptile Seed coat Epicotyl
Hypocotyl
Radicle
2 Cotyledons
(a) Common garden bean, a eudicot with thick cotyledons
Seed coat
Endosperm
Cotyledons
Epicotyl
Hypocotyl
Radicle
(b) Castor bean, a eudicot with thin cotyledons
Figure 38.8 Seed structure
Scutellum
(cotyledon)
Pericarp fused
with seed coat
Endosperm
Coleoptile
Epicotyl
Hypocotyl
Coleorhiza
Radicle
(c) Maize, a monocot

11. Common garden bean, a eudicot with 2 thick cotyledons
Seed coat
Epicotyl
Hypocotyl
Radicle
Cotyledons
Figure 38.8a Seed structure
Common garden bean, a eudicot with 2 thick cotyledons

12. Pericarp fused Scutellum with seed coat (cotyledon) Endosperm
Coleoptile
Epicotyl
Hypocotyl
Coleorhiza
Radicle
Figure 38.8c Seed structure
Maize = corn , a monocot

13. Two common types of seed germination
Foliage leaves
Cotyledon
Epicotyl
Hypocotyl
Cotyledon
Cotyledon
Hypocotyl
Hypocotyl
Radicle
Seed coat
(a) Common garden bean
Foliage leaves
Figure 38.9 Two common types of seed germination
Coleoptile
Coleoptile
Radicle
(b) Maize - corn

14. Dicot: Common garden bean
Foliage leaves
Cotyledon
Epicotyl
Hypocotyl
Cotyledon
Cotyledon
Hypocotyl
Hypocotyl
Figure 38.9a Two common types of seed germination
Radicle
Seed coat
Dicot: Common garden bean

15. Monocot: Maize - Corn Foliage leaves Coleoptile Coleoptile Radicle
Figure 38.9b Two common types of seed germination
Radicle

16. Developmental origin of fruits
Stigma
Carpels
Style
Stamen
Flower
Petal
Ovary
Stamen
Stamen
Sepal
Stigma
Ovary
(in receptacle)
Ovule
Ovule
Pea flower
Raspberry flower
Pineapple inflorescence
Apple flower
Each segment
develops
from the
carpel
of one
flower
Remains of
stamens and styles
Carpel
(fruitlet)
Stigma
Sepals
Seed
Ovary
Figure Developmental origin of fruits
Stamen
Seed
Receptacle
Pea fruit
Raspberry fruit
Pineapple fruit
Apple fruit
(a) Simple fruit
(b) Aggregate fruit
(c) Multiple fruit
(d) Accessory fruit

17. Dispersal by Water
Figure Fruit and seed dispersal
Coconut

18. Dandelion “parachute”
Dispersal by Wind
Winged seed
of Asian
climbing gourd
Dandelion “parachute”
Figure Fruit and seed dispersal
Winged fruit of maple
Tumbleweed

19. Dispersal by Animals Barbed fruit Seeds in feces Seeds carried to
Figure Fruit and seed dispersal
Seeds carried to
ant nest
Seeds buried in caches

20. Some floral adaptations that prevent self-fertilization
Sagittaria latifolia staminate flower (left) and carpellate flower (right)
(a)
Figure Some floral adaptations that prevent self-fertilization
Stamens
Styles
Styles
Stamens
Thrum flower
Pin flower
(b) Oxalis alpina flowers

21. Floral Adaptations that prevent self-fertilization: stamens and styles mature at different times or are arranged to prevent self pollination / self fertilization.
Stamens
Styles
Styles
Stamens
Figure 38.13b Some floral adaptations that prevent self-fertilization
Thrum flower
Pin flower
Oxalis alpina flowers

22. Test-tube cloning of carrots
Figure Test-tube cloning of carrots
(a) Undifferentiated carrot cells
(b) Differentiation into plant

23. Protoplasts
Figure Protoplasts
50 µm

24. Maize - Corn: a product of artificial selection
Figure Maize: a product of artificial selection
For the Discovery Video Colored Cotton, go to Animation and Video Files.

25. “Golden Rice” and prevention of blindness associated with vitamin A deficiency
Genetically modified rice
Figure “Golden Rice” and prevention of blindness associated with vitamin A deficiency
Ordinary rice

26. Endosperm nucleus (3n) (2 polar nuclei plus sperm) Zygote (2n)
Review
Endosperm
nucleus (3n)
(2 polar nuclei
plus sperm)
Zygote (2n)
(egg plus sperm)

27. You should now be able to:
Describe how the plant life cycle is modified in angiosperms.
Identify and describe the function of a sepal, petal, stamen (filament and anther), carpel (style, ovary, ovule, and stigma), seed coat, hypocotyl, radicle, epicotyl, endosperm, cotyledon.
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

28. You should now be able to:
Distinguish between complete and incomplete flowers; bisexual and unisexual flowers; microspores and megaspores; simple, aggregate, multiple, and accessory fruit.
Describe the process of double fertilization.
Describe the fate and function of the ovule, ovary, and endosperm after fertilization.
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

29. Explain the advantages and disadvantages of reproducing sexually and asexually.
Name and describe several natural and artificial mechanisms of asexual reproduction.
Discuss the risks of transgenic crops and describe four strategies that may prevent transgene escape.
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings