Presentation on theme: "Sexual Reproduction in Flowering Plants Visit:"— Presentation transcript:
Sexual Reproduction in Flowering Plants Visit:
Alternation of Generations in Plants Life Cycle of a Typical Animal Life Cycle of a Typical Plant
Flowers and Fossils
The Rise and Fall of Dinosaurs Dinosaurs are found in the fossil record starting about 230 million years ago. The last dinosaurs bcame extinct about 65 million years ago. Impact Hypothesis: A 10km-wide meteorite had smashed into the Yucatan peninsula in Mexico, causing worldwide forest fires, tsunamis several kilometres high, and an 'impact winter'
The Rise and Fall of Dinosaurs Evidence prior to impact that diversity of dinosaur species was on the decline. Climate change? Rise of Angiosperms? –Sometime in the Mid- Cretaceous Period; between 144 to 65 Million Years Ago –Corresponds with a decline of the gymnosperms and rise of animal groups
Why Dinosaurs Went Extinct! The Far Side by Gary Larson.
Some Example Stories: Perfect Flowers: Pea exclusively self-pollinating Hibiscus self-pollinating if not crossed Cherry self-incompatible only outcrosses Imperfect Flowers: Begonia unisexual but monoecious Holly unisexual and dioecious Variable: Cucumber male, perfect, female, parthenocarpic
Basic Flower Structure stigma style ovary locule ovule carpel gynoecium pollen anther filamentstamen androecium petal corolla perianth sepal calyx receptacle pedicel Perianth is complete Flower is perfect Flower is monoecious superior Flower is hypogynous Pistil is simple
Basic Flower Structure stigma style ovary locule ovule carpel gynoecium pollen anther filamentstamen androecium petal corolla perianth sepal calyx receptacle pedicel Perianth is complete Flower is perfect Flower is monoecious superior Flower is hypogynous Pistil is simple This longitudinal section view does not allow us to consider symmetry
Symmetry: *=radial =bilateral Flower Formula: Symbol Sequence to Diagram Flower Number of Parts per Whorl: sepals in calyx Fusion within whorl: curved line over number Fusion between whorls: square bracket below numbers Attachment of flower parts relative to ovary: horizontal line * * 5, 5,, 5 * 5, * 5, 5,, * 5, 5, petals in corolla stamens in androecium carpels in gynoecium