BIOL 172 Lecture Notes - Lecture 3: Unikont, Dihydrofolate Reductase, Haustorium
Document Summary
Evidence that unikonta is a monophyletic group: molecular evidence. Two separate genes for enzymes in bacteria and unikonta. Amoebozoans: amoeboid (uniflagellated) but biflagellated w/ flagella. Opisthokonts: flagellated stage w/ single, posterior flagellum. Characteristics that define fungi: eukaryotic heterotrophs that feed by absorption. Absorption: fungi secrete enzyme to digest food, then absorb it. Mycelium: network of hyphae of whole fungus. Yeast: unicellular, reproduces asexually by budding or fission. Dimorphic: yeast and hyphae occurs in same species. Why fungi are significant: are decomposers and parasites. Fungal life cycles: form heterokaryotic hyphae after plasmogamy. Heterokaryotic stage: unfused nuclei in cytoplasm: fusion of nuclei in karyogamy, meiosis of zygote. Paraphyletic: descended from a common evolutionary ancestor, but not including all the descendant groups. Zygosporangium: characteristic that is unique to the zygomycetes. Borne on hyphae, as opposed to sporangium, as shown on zygomyetes" zygosporangium. Young dikaryotic asci line base of ascocarp: karyogamy, meiosis, mitosis.
