Plant Reproduction “Sexual encounters of the floral kind”

Gardening Plants AnnualsAnnuals BiennialsBiennials PerennialsPerennials

Annuals 1 growing season Corn, marigolds Produces seeds for next year

Biennials Live 2 years Die back to roots Produce seeds 2 nd year Carrots Foxglove

Live more than 2 years Trees shrubs Perennials

Reproductive organs Gymnosperms- Cones Angiosperms flowers

Cones Male pollen zygotes land near ovules, sends a pollen tube and fertilizes eggs

Flowers There are many parts to know with 4 main structures

Sepals Leaves covering developing flower Calyx

Petals Colored part of flower Corolla advertises

Stamen Male part of flower Filament & Anther microsporangia

Stamen Stame picture

Carpel Female part of flower Pistil, ovary, stigma, style megasporangia

Carpel picture Carpel

Female Gametophyte Ovules go through meiosis 4 cells produced 3 die 8 nuclei in embryo sac

6 go to opposite ends 2 stay in the center “Polar nuclei” 1 at lower end survives to become egg nucleus

Male Gametophyte Anther produce pollen chambers Microspore meiosis Each pollen grain splits

Pollen grains have 2 nuclei -Tube nucleus -Generative nucleus

Pollination Transfer of pollen from anther to stigma

Self-pollination Same flower transfer pollen from anther to stigma heliconia

Cross Pollination Different flowers transfer pollen from anther to stigma

Fertilization Pollen on a stigma grows a pollen tube

Double fertilization 1 sperm → egg nucleus Embryo formed 1 sperm → polar nuclei Endosperm seed leaves Humans eat endosperm

Formation of seed

cotyledons Store food

epicotyl Plant stem -apical meristem

hypocotyl Plant stem

radicle Plant root

Seed Development

Germination Seeds soak water & crack seed coat Pushes through dirt to get to sun

Seed Dormancy Seed doesn’t germinate immediately

benefits Coconut- moves across ocean Temp changes cold Fires for pines

Vegetative Reproduction

Strawberries, Bamboo, banana make shoots

Cuttings Cut a stem with lateral buds & place in soil

Layering Make cuts in the plant and cover with root powder

Grafting & budding Cut one plant and insert into another.