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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
Basic Flower Morphology
http://www.bbc.co.uk/scotland/education/bitesize/standard/img/biology/flower.jpg
Look at the two flowers you have
1. Carefully remove each of the parts
2. Lay them out in order in front of you
3. Note shape, size and appearance
http://images.google.com/imgres?imgurl=www.hcs.ohio-state.edu/hcs300/glossary/jpeg/rayfloret.JPG&imgrefurl=http://www.hcs.ohio-state.edu/hcs300/glossary/flower.htm&h=600&w=600&sz=29&tbnid=WZ3lvCkOHBAJ:&tbnh=133&tbnw=133&prev=/images%3Fq%3Dflower%2Bstructure%26start%3D40%26hl%3Den%26lr%3D%26ie%3DUTF-8%26sa%3DN
Radial - free and fused petals
Bilateral Symmetry
Flower Parts - Calyx
1. leaf-like structures called sepals• spongy parenchyma• often have functional stomata• lots of vascular bundles
2. protect the flower bud
3. seldom used to attract pollinators(but can be showy)
4. usually green and tough, but a lot of variation on this theme
Flower Parts - Corolla
1. Whorls of petals
2. Leaf-like developmentally and structurally
3. Biochemically different due to presence of pigments and oils
4. Petals attractive pollinators
5. Vary in pattern, shape, color, odor, size, etc.
Flower Parts - Perianth
1. outer envelope enclosing a flower
2. made up of either:• outer calyx and
inner corolla• calyx or corolla• calyx and corolla
combined and undifferentiated from one another
Carpel = Female
Stamen = Male
Morphology of Reproductive Tissues
1. 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
Androecium = whorl of male reproductive tissue
http://botit.botany.wisc.edu:16080/images/130/Angiosperm/Lilium/Adroecium/Mature_pollen_MC.html
Gametangia
Pollen Grains
Paired Microsporangia
Filament
•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
Gynoecium - whorl of female reproductive tissue
Stigma
Style
OvaryCarpel
1. Carpel (pistil)• More leaf-like than
stamen• Epidermis may have
functional stomata• Up to 3 vascular
bundles2. Stigma
• Receptive surface for pollen (may be wet or dry)
3. Style • 1 vascular bundle• Transmittal for
germinated pollen grain4. Ovary - contains eggs
within embryo sac
Megaspore mother cell
http://botit.botany.wisc.edu:16080/images/130/Angiosperm/Lilium/Gynoecium/
Embryo Sac
Ovary
http://www.uri.edu/artsci/bio/plant_anatomy/images/146.gif
Longitudinal section of a flower Petal
Anther connected to filament
StigmaOvary
Style
Mini-Quiz : Label the Parts
http://academic.regis.edu/tnakamur/midterm%20practice/flower.jpeg
C
D
E
F
G
Mini-Quiz : Label the Parts
http://academic.regis.edu/tnakamur/midterm%20practice/flower.jpeg
A.Stigma
B.Sepal
C.Style
D.Petal
E. Anther
F. Ovary
G.Filament
C
D
E
F
G
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
http://scidiv.bcc.ctc.edu/rkr/Biology203/lectures/flowerreproduction/image003.jpg
Correspondence between flower and fruit
http://w3.dwm.ks.edu.tw/bio/activelearner/35/images/ch35summary.gif
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