Presentation on theme: "Classify Which plant structures are male sexual organs and which are female sexual organs Apply Concepts Relate the characteristics of angiosperms reproduction."— Presentation transcript:
1 Classify Which plant structures are male sexual organs and which are female sexual organs Apply Concepts Relate the characteristics of angiosperms reproduction to angiosperm successReview Define vegetative reproductionCompare and Contrast Make a compare contrast table comparing alternation of generations in flowering plants and green algae (22.2)
2 Ch 24 Plant Reproduction and Response 24.1 Reproduction in Flowering Plants
3 Structure of FlowersReproductive organs that are composed of four kinds of specialized leaves:Sepals, petals, stamens, and carpels.
4 Sepals Outermost circle of floral parts Enclose the bud before it opensProtect the flower while it is developing.
5 Petals Found just inside the sepals Colors, number, and shapes of such petals attract insects and other pollinators to the flower.
6 Stamen Male parts of the flower Consists of a stalk called a filament with an anther at its tipAntherStructure that produces pollen grains.
7 Carpels Produce and shelter the female gametophytes and seeds Ovary Contains one or more ovules where female gametophytes are produced.
8 Carpels Style Stigma Stalk of carpel Sticky or feathery portion at tip of carpel to capture pollen.
9 CarpelPistilSingle carpel or several fused carpels.
10 Angiosperm Life CycleFertilization in angiosperms is distinct from other plantsTwo fertilization events take place- one produces the zygote and the other a tissue, called endosperm, within the seed.
11 Angiosperm Life CycleAlternation of generations between a diploid sporophyte phase and a haploid gametophyte stageMale and female gametophytes live within the tissues of the sporophyte.
12 Development of Male Gametophytes The male gametophytes (pollen grains) develop inside anthersMeiosis produces four haploid spore cells.
13 Development of Male Gametophytes Each spore undergoes one mitotic division to produce the two haploid nuclei of a single pollen grainTwo nuclei are surrounded by a thick wall that protects themale gametophyte.
14 Development of Female Gametophytes Develop inside each carpel of a flowerOvules (future seeds) are enveloped in a protective ovary (future fruit).
15 Development of Female Gametophytes Single diploid cell goes through meiosis to produce four haploid cells, three of which disintegrate.
16 Development of Female Gametophytes Remaining cell undergoes mitosis, producing eight nucleiEmbryo sacEight nuclei and the surrounding membrane.
17 Development of Female Gametophytes Cell walls form around six of the eight nucleiOne of the eight nuclei near the base of the gametophyte, is the nucleus of the egg (female gamete)Will fuse with male gamete, form zygote and become sporophyte if fertilization occurs.
18 Pollination Transfer pollen to the female portions of the flower Can use wind or an animal pollinatorWind pollination is less efficientRelies on favorable weather and sheer numbers of pollen grains.
19 Animal Pollinated Plants Variety of adaptations to attract and reward animalsSuch as bright colors and sweet nectarAnimals have evolved body shapes to reach nectar deep within certain flowersInsect pollinationPlant benefits- efficient pollinationInsect benefits- source of food.
20 Fertilization Pollen grain lands on the stigma of a flower Pollen tube begins to growPollen grain has two cellsCell divides and forms two sperm cellsCell becomes the pollen tube.
21 Pollen tube grows into the style Reaches the ovaryEnters an ovule.
22 Double FertilizationOne of the sperm nuclei fuses with the egg nucleus to produce a diploid zygoteOther sperm nucleus fuses with two polar nuclei in the embryo sac to form a triploid (3N) cell or endospermEndospermFood-rich tissue known which nourishes the seedling as it grows.
24 Flowering plant spends very little in the way of food resources on producing seeds from ovules until double fertilization has actually taken placeMake more seeds.
25 Vegetative Reproduction Asexual reproductionEnables a single plant to produce offspring genetically identical to itself by mitosisEnables a single plant to produce offspring genetically identical to itself by mitosis.
26 New plants may grow from roots, leaves, stems, or plantlets Single plant can reproduce quickly.
27 GoodSingle plant produces genetically identical offspring, enabling well-adapted individuals to rapidly fill a favorable environment.
28 BadDoes not produce new combinations of genetic traits, which may be valuable if conditions in the physical environment change.
29 GraftingMethod to reproduce seedless plants and varieties of woody plants that cannot be propagated from cuttingsPlants need to be closely related.