Angiosperm Reproduction

Bio 1400Fa 2104

Major Evolutionary Advances

Flowers - 140 mya

5,000mya

4,000mya

3,000mya

2,000mya

1,000mya

EarthForms

ProkaryoticCells

EukaryoticCells

MulticellularPlants

Vascular

tissue

Seeds

Flowers

Life - 3,800 myaProkaryotic cell/autotrophic

Eukaryotic cell - 1,400 mya

Multicellar plants - 1,000 mya

Vascular tissue - 430 myaNeeded on land - why?

Seeds - 350 mya

Place on the time scale, the following events:

1. Earth2. Prokaryotes3. Eukaryotes4. Multicellular life5. Vascular tissue6. Seeds7. Flowers

Floral Series• Calyx

• individual parts are sepals

• Corolla• individual parts are petals

• Androecium• individual parts are stamens

• filament, anther - produce pollen

• Gynoecium• individual parts are carpels

• stigma – receives pollen (male gametophyte)

• style – place of pollen tube growth• connects stigma to ovary

• ovary – produce ovules (female gametophyte)• ripens into fruit

Sexual Reproduction

Four events must occur for successful reproduction in angiosperms:

1. Pollination2. Pollen grain growth to ovule3. Successful fertilization4. Successful seed development

Fertilization

megagametophyte(female gametophyte)

microgametophyte(male gametophyte)

ovule

Fertilization

• Pollination: transfer of pollen grains from anther to pistil

• Pollen grain onto stigma• Germination - tube cell

produces pollen tube, generative cell divides to form 2 sperm cells

• Double Fertilization:• 2 sperm enter

embryo sac: • 1 sperm fertilizes egg to form zygote• other sperm fertilizes polar nuclei to

form endosperm