Plant Adaptations for Success on Land Vascular tissue Evolution of the seed that provides food and protection Many methods of seed dispersal Evolution of pollen

Flowering Plant (Angiosperm) Reproduction ?

What is the function of flowers? Reproduction – Attract Pollinators – Produce reproductive cells (pollen and ovules) – Form fruit and seeds once fertilized

Parts of a Flower

Parts of the Flower Sepals = enclose flower bud Petals = attract pollinators Carpel = female reproductive organ – Stigma= receives pollen – Style= leads to ovary – Ovary= contains ovules (female gametophyte)

Parts of a Flower (contd.) Stamen = male reproductive organ – Anther = produce pollen (male gametophyte) – Filament = holds anther Pollen = each contains 2 cells- tube cell and a cell that makes two sperm

formed by meiosis and contains 4 haploid cells 3 disintegrate 1 forms 7 cells by mitosis 1 becomes an ovum, and 1 becomes a cell with 2 nuclei (polar body) Ovule Formation

Reproduction 1.Pollination 2.Pollen tube carrying sperm grows toward ovule 3.Double Fertilization Sperm + Egg= 2n cell (embryo and cotyledons) Sperm + Polar body = 3n cell (endosperm)

4. Ovule becomes a seed 5. Ovary becomes fruit Reproduction Continued…

Seeds and Embryo Growth

After fertilization cells divide and anchor embryo to parent Other cells divide to form the embryo

Continued… Endosperm and embryo surrounded by seed coat (dormant until germination) – Requires correct temp and water – Enzymes digest endosperm (nutrients) Cotyledons develop Store food Embryonic shoot develops (will be stem and leaves) Epicotyl (above the cotyledon) Hypocotyl (below the cotyledon) Embryonic root develops (radicle)