1. Reproductive Morphology
Flower comprised of whorls or layers
House reproductive organs
Attract pollinators or disperse pollen
Develop new zygote and “prepare” it for dispersal as a seed
MONOCOT
DICOT

2. Basic Flower Morphology
Look at the two flowers you have
Carefully remove each of the parts
Lay them out in order in front of you
Note shape, size and appearance

3. Radial - free and fused petals
Bilateral Symmetry
Radial - free and fused petals

4. Flower Parts - Calyx leaf-like structures called sepals
spongy parenchyma
often have functional stomata
lots of vascular bundles
protect the flower bud
seldom used to attract pollinators(but can be showy)
usually green and tough, but a lot of variation on this theme

5. Flower Parts - Corolla Whorls of petals
Leaf-like developmentally and structurally
Biochemically different due to presence of pigments and oils
Petals attractive pollinators
Vary in pattern, shape, color, odor, size, etc.

6. Flower Parts - Perianth
outer envelope enclosing a flower
made up of either:
outer calyx and inner corolla
calyx or corolla
calyx and corolla combined and undifferentiated from one another

7. Morphology of Reproductive Tissues
Carpel = Female
Stamen = Male

8. Androecium = whorl of male reproductive tissue
Filament
Spongy parenchyma and epidermis with stomata
May have waxy cuticle
At least one vascular bundle
2. Anther
Held to filament with connective parenchyma
Paired microsporangia housing the gametangia
Epidermis may have stomata
Produces pollen
Anther
Filament
Stamen

9. Paired Microsporangia
Gametangia
Paired Microsporangia
Filament
Pollen Grains

10. Pollen is highly variable in shape, but distinctive for species and genera
Some kinds can persists in the fossil record allowing for reconstructing plant distributions

11. Gynoecium - whorl of female reproductive tissue
Carpel (pistil)
More leaf-like than stamen
Epidermis may have functional stomata
Up to 3 vascular bundles
Stigma
Receptive surface for pollen (may be wet or dry)
Style
1 vascular bundle
Transmittal for germinated pollen grain
Ovary - contains eggs within embryo sac
Stigma
Style
Ovary
Carpel

12. Megaspore mother cell Ovary Embryo Sac

15. Longitudinal section of a flower Petal
Anther connected to filament
Stigma
Ovary
Style

17. Mini-Quiz : Label the PartsC D E F G

18. Mini-Quiz : Label the PartsC D E F G
Stigma
Sepal
Style
Petal
Anther
Ovary
Filament

19. Angiosperm Life History – Alternation of Generations
Sperm (Gamete = n) Egg (Gamete = n)
|____________________________| |
Zygote (2n)
Mitosis
Embryo (in seed)
Plant (Sporophyte = 2n)
Flower
________________________________________________________
| |
Anther (Microsporangium) Ovule (Megasporangium)
| |
Meiosis Meiosis
Microspore (n) Megaspore (n)
| |
Mitosis Mitosis
| |
Pollen Grain (Microgametophyte n) Embryo Sac (Megagametophyte n)
Sperm (n) Egg (n)
Angiosperm Life History – Alternation of Generations

22. Correspondence between flower and fruit