Flowers Laboratory

1
Flowers Laboratory
Flower Structure and Interactionswith
Pollinators
2
Flowering Plant Reproduction

• Flowers are modified leaves, specialized for
  reproduction.
• Flowers form on the diploid Sporophyte
• Flower parts undergo meiosis to produce haploid
  Gametophytes
• pollen grain
• embryo sac

3
A Complete Flower Has Both Male and Female Parts
Anther
Filament
Stigma
Petal
Style
Sepal
All PetalsCorolla
Ovary
All SepalsCalyx
4
Plant Reproduction
Flower Part Function
Sepals Enclose and protect bud
Petals Attract pollinators
Stamen Produce pollen in anther
Pistil (carpel) Produce ovule in ovary
5
Flowering Plant Life Cycle
MatureSporophyte
Megaspore(female)
meiosis
Microspore(male)
SpermCells
mitosis,differentiation,growth
mitosis,differentiation
mitosis,differentiation
MaleGametophyte(Pollen)
EggCell
FemaleGametophyte(Embryo Sac)
fusionto formzygotein ovary
Diploid2n
Haploid1n
6
Pollination andFertilization in a Flower
Mature PollenGrain
Sperm Cells
Tube Cell Nucleus
1. pollen grainsland on stigma
3a Fusion of 2ndsperm twopolar nuclei
2. pollen tubes growdown style to ovary
Stigma
3. doublefertilization
Style
Sperm
3b Fusion ofsperm egg
Ovule
Polar nuclei
Ovary
Egg
7
Development of Fruit and SeedsFrom Flower Parts
Endosperm
Triploid Endosperm Cell
FreshFruit
Ovary
SeedCoat
Integument
Zygote
Embryo

• Seed fertilized ovule embryo endosperm
  seed coat
• Fruit ovary wall, mechanism for seed dispersal
  

8
Comparing Monocot and Dicot Plants
9
Flower Symmetry
Radial Symmetry(Regular)
Bilateral Symmetry(Irregular)
10
Ovary Position
11
Coevolution of Plant and Pollinator
12
Wind Pollination
13
Pollination by Beetles
14
Pollination by Ants
15
Pollination by Carrion Flies
16
Pollination by Mammals
17
Pollination by Wasps
18
Pollination by Bees
19
Ultraviolet Patterns Guide Bees to Nectar
HumanVision
BeeVision
20
Impersonating a Pollinator
21
Pollination by Moths
22
Pollination by Hummingbirds
23
Pollination by Butterflies
24
Composite Flowers
25
CLEAN UP!

• Leave plant specimens in orderly arrays
• Discard dissected flower parts in the trash
• Return any microscopes to their cabinets
• Thank you!

26
Worksheet

• Turn in pages 155-157 from lab manual
• Record your answer and reasoning for any 10
  specimens, making sure to write the answer on the
  line that matches the specimen number
• Be sure your instructor checks your completed
  worksheet before you leave the lab