BCOR 12 1st Edition Lecture 14 Outline of Last Lecture I Lecture 12 Quick Review nonvascular vs vascular II Seedless Vascular Plants III Shared Derived Characters of Vascular Plants IV CHAPTER 30 Vascular Plants with Seeds V Key Adaptations of Seed Plants VI Major Trends of Land Plant Evolutions VII Seed Components VIII Types of Gymnosperms Outline of Current Lecture I Human Welfare Plants II Seed plant reproduction vs Spore dispersing plants III Life Cycle of Gymnosperm IV Shared Derived Characters of Angiosperms V Structure of Idealized Flower VI Flower Fruit Current Lecture Human Welfare Plants Human welfare depends on seed plans for medicine oxygen food and many other things About 25 of ALL U S prescription drugs come from seed plants Modern pharmacology depends on seed plants Plants are just naturally awesome chemists Seed Plant Reproduction vs Spore dispersing Plants I Pollen and Pollination allows fertilization to occur without sperm being exposed to external environment and does not require water in order to reach the ovule These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute II III An ovule when fertilized develops in to a seed which is adapted for dispersal The gametophyte is reduced to the size of a few cells and depends on the parent sporophyte for nutrition Seeds enclosed in a cone gymnosperm Seeds enclosed in a fruit angiosperm Life Cycle of a Gymnosperm Male cones release pollen let out pollen to the wind Female cones contain ovules and receive pollen Old female cones mature ovaries contain seeds Heterospory two spores are created and one develops into the female gametophyte and the other into the male gametophyte Meiosis occurs to create microspores and megaspores which develop into the male and female gametophytes Shared Derived Characters of Angiosperms I II III Flowers Double fertilization Fruit Basal and magnoloids are the oldest flowering plants groups Basal angiosperm oldest Aimborella trichopoda is the most ancient living angiosperm Magnoloids includes laurels magnolias black pepper plants and more Monocots and eudicots are the two groups of flowering plants Monocots grasses bananas orchids and lilacs Eudicots 75 of flowering plants fit in this category oat tree maple tree cactus and many many more Structure of an Idealized Flower Petals are colorful to attract pollinators Sepal and receptable are both green Carpel female part of flower o Stigma entrance into the style o Ovary at the bottom of the style o Ovule contains the egg o Style the pipe down to the ovary Stamen male part of flower o Anther stores sperm and pollen and releases it o Filament attaches anther to rest of plant Flower Fruit Fruit mature ovary containing seeds o Can be fleshy apple peach etc o Can be dry Fruits are adapted to disperse and protect seeds Flowers attract animal pollinators Flowers help to overcome plant s challenge of dispersing genes Fruits help overcome the challenge of dispersing offspring Gymnosperms are ONLY wind pollinated Fruits increase range of dispersal