1. Angiosperm Reproduction
Chapter 19

2. Major Evolutionary Advances
Life - 3,800 mya
Prokaryotic cell/autotrophic
Place on the time scale, the following events:
1. Earth
2. Prokaryotes
3. Eukaryotes
4. Multicellular life
5. Vascular tissue
6. Seeds
7. Flowers
Eukaryotic cell - 1,400 mya
Multicellar plants - 1,000 mya
Vascular tissue mya
Needed on land - why?
Seeds mya
Flowers mya
Earth
Forms
Prokaryotic
Cells
Eukaryotic
Cells
Multicellular
Plants
Vascular
tissue
Flowers
5,000
mya
4,000
3,000
2,000
1,000
Seeds

3. Flower variation Complete Incomplete has all 4 whorls
lacks one or more of whorls (sepals, petals, stamens or carpels)

4. Flower variation Perfect Imperfect both androecium and gynoecium
carpellate or staminate flower only
if both carpellate and staminate flowers are on same plant called monoecious
if on different plants called dioecious

5. Fertilization
Pollination: transfer of pollen grains from anther to pistil
Pollen grain onto stigma
Germination - tube cell produces pollen tube, generative cell divides to form 2 sperm cells
Double Fertilization:
2 sperm enter embryo sac:
1 sperm fertilizes egg to form zygote
other sperm fertilizes polar nuclei to form endosperm

6. Sexual Reproduction
Four events must occur for successful reproduction in angiosperms:
Pollination
Pollen grain growth to ovule
Successful fertilization
Successful seed development

7. Sexual Reproduction Inbreeding Outcrossing
Result of self-pollination & self-fertilization
Results in inbreeding depression
Outcrossing
Result of cross-pollination & cross-fertilization
Results in hybrid vigor
What process is “best”? Why?
How do plants promote this?

8. Sexual Reproduction Unisexual flowers Monoecious plants
Dioecious plants

9. Sexual Reproduction Bisexual flowers
Hibiscus
Bisexual flowers
Protandry - stamens mature before stigma
Protogyny - stigma matures before stamens
Heterostyly - physical separation between stigma and stamen
Epilobium (fireweed)
Protandry
Magnolia

10. Sexual Reproduction Bisexual flowers Self-incompatibility
Pollen grain-stigma surface: no germination
Pollen tube growth: tube “dies”
Fertilization: inviable zygotes
Amarylis

11. Pollination
Define:
transfer of pollen to stigma
How is self-fertilization prevented (or reduced) through pollination mechanisms?
unisexual flowers (monoecious plants)
unisexual flowers (dioecious plants)
protandry
protogyny
heterostyly

12. Fertilization: Define:
combining of sperm + egg AND sperm + polar nuclei = double fertilization
ovule

13. Fertilization megagametophyte microgametophyte (female gametophyte)
ovule

14. Fertilization

15. Fertilization What occurs after double fertilization?
embryo development
next generation
endosperm development
nourishment for embryo
What structure is formed?
seed
embryo
endosperm
seed coat
Where is the seed housed?
inside ovary
matures into a fruit
ovary wall = pericarp

16. Seed germination & growth

17. How might reproductive success be measured in an angiosperm?

18. Gyno-dioecious species Hermaphroditc flowers on some plants
Funk, Lisa A comparison of reproduction in self and outcrossed purple poppy mallow flowers (Callirhoe involucrata). Results presented at the 1997 Nebraska Academy of Sciences Annual Meeting.
Gyno-dioecious
species
Hermaphroditc
flowers on some plants
Male-sterile flowers on other plants

19. 4 Treatments Fruit set measured Selfed Outcrossed Pollinator excluded
Funk, Lisa A comparison of reproduction in self and outcrossed purple poppy mallow flowers (Callirhoe involucrata). Results presented at the 1997 Nebraska Academy of Sciences Annual Meeting.
4 Treatments
Selfed
Outcrossed
Pollinator excluded
Control
Fruit set measured

20. What conclusions can be drawn?

21. What conclusions can be drawn?
Funk, Lisa A comparison of reproduction in self and outcrossed purple poppy mallow flowers (Callirhoe involucrata). Results presented at the 1997 Nebraska Academy of Sciences Annual Meeting.
What conclusions can be drawn?
What is the role of gyno-dioecy in plant reproduction and reproductive success in Callirhoe involucrata?