BCOR 12 1st Edition Lecture 13Outline of Last Lecture I. Land Plant OriginII. BryophytesIII. Obstacles and Rewards for moving to landIV. Shared Derived Traits of the Land plantsV. Key features of Non-vascular plants/bryophytesVI. Alternation of GenerationsOutline of Current Lecture I. Lecture 12 Quick Review - nonvascular vs. vascular II. Seedless Vascular PlantsIII. Shared Derived Characters of Vascular PlantsIV. CHAPTER 30 – Vascular Plants with SeedsV. Key Adaptations of Seed PlantsVI. Major Trends of Land Plant EvolutionsVII. Seed ComponentsVIII. Types of GymnospermsCurrent LectureLecture 12 Review- Nonvascular plants (bryophytes) – lack vascular tissue and are rather small. Includes:o Mosseso Liverwortso Hornworts Hornworts and liverworts were the pioneers of new landscapes- Vascular plants – have vascular tissues:o Xylem – transports water and mineralso Phloem – transports sugar and other organic material- Seedless vascular plants were the first plants to grow tallTwo Major Lineages of Seedless Vascular Plants:1. Lycophytes – club mosses, spike mosses, quillworts2. Pterophytes– ferns, horsetails, whisk fernsThese 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.- Evolution of true roots and leaves combined with the addition of vascular tissue is what allowed seedless vascular plants to grow tall (sometimes 80 ft. tall!)- The most prevalent seedless vascular plant in our current time period is the fernShared Derived Character of Seedless Vascular PlantsI. Vascular tissues (xylem and phloem)II. Well developed roots and leavesIII. Life cycles with dominant sporophytes (the diploid generation)IV. Spore (haploid generation) bearing leaves called sporophyllsAlternation of Generations review:Sporophytemeiosis occurs created spore spore germinates and grows into a gametophytegametophyte produces gametesgametes meet and fertilization occurs embryo grows into the Sporophyte- In vascular plants the gametophyte is bisexual and produces both sperm and eggs- In seedless vascular plants, the sporophyte starts growing out of the gametophyte and originally becomes independent from the gametophyte- Water is required for fertilization in seedless vascular plants and nonvascular plantsCHAPTER 30 – Seed Plants- Seed plants originated sometime in the Permian time period for the climate became drier and water-required fertilization was not favored- Pollen grain – contains the sperm and a tough coat of sporopollenin (a polymer) to protect is- Seed – contains the plant embryo (diploid after fertilization) along with a source of food and a tough seed coat- Endosperm – the source of food within a seed- Further protection of the gametes and embryo is was allowed seed plants to thriveTwo Major Lineages:1. Gymnosperms: “naked seeds” – seeds are usually contained within cones2. Angiosperms: flowering plants – seeds are contained within fruits- Fruit – additional protective tissue around seedsKey Adaptations of Seed Plants1. Reduced gametophyte generation size (microscopic)2. Seeds3. Pollen and pollinationTwo ways to pollinate:o Animal pollinators (angiosperms utilize this)o Wind pollination (both gymnosperms and angiosperms utilize this)4. Heterosporya. Male spore (microspore) develops into male gametophyte – pollen grainb. Female spore (megaspore) develops into female gametophyte – ovuleMajor Trends of Land Plant Evolution- Decreased in size and independence of gametophyte generation- Increase in sporophyte generation prominenceSeed Components- Embryo- Endosperm – derived from female gametophyte- Seed CoatSeeds can remain dormant for long periods of time until the environment conditions are favorable for growthGroups of Gymnosperms- Gingko (trees now)- Conifers (ex. pine) – most species in this group- Gynetophytes – shrubs and vines- Cycads – extremely large fern-like