1. Plant Reproduction

2. Asexual Reproduction
Asexual reproduction is natural “cloning.” Parts of the plant, such as leaves or stems, produce roots and become an independent plant.
List some benefits and some drawbacks to asexual reproduction.
Fast, no mate required.
Beneficial for plants that must compete for scarce resources.
However, all individuals are genetically identical.

3. Sexual Reproduction
Sexual reproduction requires fusion of male cells in the pollen grain with female cells in the ovule.
List some advantages and drawbacks to sexual reproduction.
Fusion of egg and sperm cells.
May be limited to a certain season.
Slower than asexual reproduction.
Allows genetic mixing, increasing variability in a population.

4. 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.

5. Animals vs. Plants Plant Reproduction Animal Reproduction Life cycle
Alternation of generations
No alternation of generations
Gametes
Haploid gametes
Spores
Haploid spores
No spores
Gametes made by
Haploid gametophyte, by mitosis
Diploid organism, by meiosis
Spores made by
Diploid sporophyte, by meiosis

6. Non-flowering plants
Mosses, ferns, and related plants have motile, swimming sperm.
What kind of environmental conditions would be required for reproduction in these plants?
What kinds of limits does external reproduction impose on these plants?
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.

7. Flowers

8. Flower Parts

9. Basic Flower Structure
stigma
carpel
gynoecium
locule
Flower is perfect
Flower is monoecious
style
pollen
ovule
ovary
anther
filament
stamen
androecium
petal
corolla
sepal
perianth
receptacle
calyx
Perianth is complete
pedicel

10. Some Example Stories:
Perfect Flowers: Pea exclusively self-pollinating
Hibiscus self-pollinating if not crossed
Cherry self-incompatible only outcrosses
Imperfect Flowers: Begonia unisexual but monoecious
Holly unisexual and dioecious
Variable: Cucumber male, perfect, female, parthenocarpic

11. Basic Flower Structure
stigma
carpel
Pistil is simple
gynoecium
locule
Flower is perfect
Flower is monoecious
style
pollen
ovule
ovary
anther
superior
filament
stamen
Flower is hypogynous
androecium
petal
corolla
sepal
perianth
receptacle
calyx
Perianth is complete
pedicel

12. Ovary Superior
Flower Hypogynous
Ovary Half-Superior
Flower Perigynous
Ovary Half-Inferior
Flower Epigynous
Ovary Inferior

13. Basic Flower Structure
stigma
carpel
Pistil is simple
gynoecium
locule
Flower is perfect
Flower is monoecious
style
pollen
ovule
ovary
anther
superior
filament
stamen
Flower is hypogynous
androecium
petal
corolla
sepal
perianth
receptacle
calyx
Perianth is complete
pedicel
This longitudinal section view does not allow us to consider symmetry

14. Flower Formula: Symbol Sequence to Diagram Flower * 5, 5, , 5 * 5,
Symmetry: *=radial †=bilateral
* 5, 5, , 5
* 5,
* 5, 5,
* 5, 5, , *
Number of Parts per Whorl:
sepals in calyx
petals in corolla
stamens in androecium
carpels in gynoecium
Fusion within whorl:
curved line over number
Fusion between whorls:
square bracket below numbers
Attachment of flower parts relative to ovary:
horizontal line

15. 1 1 1 Ovary Superior Flower Hypogynous Ovary Half-Superior
Flower Perigynous 1
Ovary Half-Inferior
Flower Epigynous
Ovary Inferior 1

16. 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.

17. Gametogenesis: Male

18. Gametogenesis: Female

19. Double Fertilization

20. Flower to Fruit

21. Ovule to Seed

22. Seed Anatomy

23. Seed Germination