Flowers Laboratory Flower Structure and Interactions with Pollinators

Flowering Plant Reproduction Flowers are modified leaves, specialized for reproduction.Flowers are modified leaves, specialized for reproduction. Flowers form on the diploid SporophyteFlowers form on the diploid Sporophyte Flower parts undergo meiosis to produce haploid GametophytesFlower parts undergo meiosis to produce haploid Gametophytes –pollen grain –embryo sac Pollen grains embryo sac Flower Sporophyte Gametophytes

A Complete Flower Has Both Male and Female Parts Sepal Petal Ovary Style Stigma PistilPistil Anther Filament StamenStamen All Sepals=Calyx All Petals=Corolla

Plant Reproduction Flower Part Function Sepals Enclose and protect bud Petals Attract pollinators Stamen Produce pollen in anther Pistil (carpel) Produce ovule in ovary

Flowering Plant Life Cycle Haploid 1n Diploid 2n Mature Sporophyte meiosis Megaspore (female) Microspore (male) mitosis, differentiation mitosis, differentiation Male Gametophyte (Pollen) Sperm Cells Female Gametophyte (Embryo Sac) Egg Cell fusion to form zygote in ovary mitosis, differentiation, growth

Mature Pollen Grain Pollination and Fertilization in a Flower Tube Cell Nucleus Sperm Cells 1.pollen grains land on stigma Stigma Style Ovary 2.pollen tubes grow down style to ovary Sperm Egg 3bFusion of sperm + egg 3aFusion of 2 nd sperm + two polar nuclei 3.double fertilization Polar nuclei Ovule

Development of Fruit and Seeds From Flower Parts TriploidEndospermCell Triploid Endosperm Cell Ovary Ovary Integument Integument Zygote Zygote EndospermEndosperm Fresh Fruit Seed Coat EmbryoEmbryo Seed = fertilized ovule = embryo + endosperm + seed coat Fruit = ovary wall, mechanism for seed dispersal

Comparing Monocot and Dicot Plants

Flower Symmetry Radial Symmetry (Regular) Bilateral Symmetry (Irregular)

Ovary Position Superior Ovary Inferior Ovary

Coevolution of Plant and Pollinator

Wind Pollination

Pollination by Beetles

Pollination by Ants

Pollination by Carrion Flies

Pollination by Mammals

Pollination by Wasps

Pollination by Bees

Ultraviolet Patterns Guide Bees to Nectar Human Vision Bee Vision

Impersonating a Pollinator

Pollination by Moths

Pollination by Hummingbirds

Pollination by Butterflies

Composite Flowers

CLEAN UP! Leave plant specimens in orderly arraysLeave plant specimens in orderly arrays Discard dissected flower parts in the trashDiscard dissected flower parts in the trash Return any microscopes to their cabinetsReturn any microscopes to their cabinets Thank you!

Worksheet Turn in pages from lab manualTurn in pages 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 labBe sure your instructor checks your completed worksheet before you leave the lab