Biology 203 1st Edition Lecture 15 Outline of Last Lecture I. Haploid vs. DiploidII. Mitosis vs. MeiosisIII. Cell division for Bacteria and ArchaeaIV. Unicellular EukaryotesV. Multicellular EukaryotesVI. Gametic Life CycleVII. Zygotic Life CycleVIII. Alternations of generationsIX. Mosses are gametophyte-dominantX. Ferns are sporophyte-dominantOutline of Current Lecture I. Flowering PlantsII. Spore and gamete productionIII. PollinationIV. Seed plant life cycle “looks” like gametic life cycleV. Dikaryotic fungi Current LectureI. Flowering plantsa. Have extremely reduced GPTsb. All the Anthophyta trees, shrubs, wildflowers, and vegetables you know are 2n SPTsc. They make flowers only for sexual reproductionII. Spore and Gamete productiona. Spores are produced via meiosis in the anthersb. These spores grow into pollen grains via mitosisc. Pollen grains are GPTs! Contain just three cells, two of which are spermd. Shapes differ dramatically among speciese. Different kinds of spores are produced via meiosis inside the immature seeds in the ovary of the flowerf. One spore grows through mitosis into a 7-celled GPT, which contains an egg, inside the developing seedThese 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.g. Pollinationi. Pollen travels to the flower of the same or a different plant ii. Pollen grain forms a pollen tube that grows down into ovuleiii. Delivers spermiv. One fertilizes egg, forming a zygote, which grows into an embryo inside the developing seedv. Ovary develops into fruitIII. Seed plant life cycle “looks” like a gametic life cyclea. GPTs are tiny and short-livedb. Either retained within the developing seed inside a flower, or a pollen grainc. Easy to miss that there is a multicellular haploid generationd. Convergent evolution in the animal and seed plant life cyclesIV. Dikaryotic Fungia. Have an alternation of generations with multiple multicellular stagesb. The Dikaryotic fungi separate the two parts of fertilization, plasmogamy and karyogamy – often by many years!c. Results in a unique condition called the dikaryon = “two nuclei” = N+Nd. Karyogamy eventually occurs within fruiting bodies to produce a diploid nucleuse. Meiosis quickly follows to produce haploid sporesf. On a basidium or inside an ascus!g. Spores disperse out into the world and germinate; grow into a haploid mycelium via mitosish. Haploid phasei. Start of Fertilization makes dikaryoni. plasmogamy (fusion of cell membranes)j. Mitosis makes dikaryotic phasek. Dikaryotic phasel. End of Fertilization makes diploidi. karyogamy (fusion of nuclei)m. Meiosis to make haploid sporesn. Mitosis to make progeny haploid phaseo. All the mushrooms you’ve seen are woven out of dikaryotic filaments: nuclear fusion doesn’t occur until right before basidiospores are producedp. The two types of nuclei cooperate to direct the construction of this complex