4 Male Reproductive Structure The stamen consists of two parts: Anther and FilamentThe anther is where meiosis occurs to produce haploid pollenThe filament is a stalk that supports the anther
5 Female Reproductive Structure The pistil consists of the stigma, style and ovaryThe sticky stigma receives the pollen from the antherThe pollen grows a tube down through the styleMeiosis occurs in the ovary to produce haploid ovules
6 Reproductive Structures Petals: colourfulstructures that attract pollinators.Sepals: surround and protect the flower bud.
7 PollinationWind, insects or other animals transfer pollen from the anther of one flower to the stigma of anotherFlowers vary depending on pollination mechanism
9 Pollination Vectors Wind Pollination: Dull, scentless flowers with reduced petalsBees/Butterfly Pollination: Brightcolor, nectaries, scent.They sip nectar, get pollen on coats,transfer pollen from flower to flowerBird Pollination: Nectaries, brightcolors, tube-like flowersMoth Pollination: White petals,open at nightFly Pollination:Rank odor, fleshcolored petals
10 Pollen Grain Anther Sac Pollen grains contain two haploid cells produced through meiosis.1- The Tube cell – will grow the pollen tube.2- The Generative cell – will go through mitosis to create two sperm cells.
11 OvaryEach ovule within an ovary has a micropyle (an opening for the pollen tube).The ovules’ megasporangium undergo meiosis to produce four haploid cells (3 die leaving 1 megaspore)The megaspore undergoes mitosis 3 times to produce 8 haploid cells within the embryo sac.
13 FertilizationAfter pollen lands on the stigma, a pollen tube grows down through the style to ovaryGenerative cell creates the two sperm nucleiDouble fertilization occurs:one sperm fertilizes the eggone sperm the two polar nuclei together
14 Result of Double Fertilization The sperm nucleus and egg nucleus join to form a 2n (diploid) embryoThe other sperm nucleus and the two polar nuclei join to form a 3n (triploid) endosperm. The endosperm is the food supply for the embryo.First link
15 Seed and Fruit Development After fertilization, the petals and sepals fall off flowerOvary “ripens” into a fruitThe ovule develops into a seed
16 Seed Dispersal Mechanisms- Allow plants to colonize new areas and avoid shade of parent plant Wind Dispersal - Flight mechanisms,like parachutes, wings, etc.Ex. Dandelion, maples, birchAnimal Dispersal - Fleshy fruits whichanimals eat, drop undigested seeds infeces or burrs which stick toanimals’ coats
17 Gravity Dispersal - Heavy nuts fall to ground and roll ex. acornsWater Dispersal - Plantsnear water create floatingfruitsex. coconuts