Lab 3 Questions Describe the differences similarities between each of the 3 domains of life o Domain Archea Prokaryotic Cell walls lack peptidoglycan Plasma membrane lipids are ether links Has several 8 12 subunits each RNA polymerase Initiator tRNA is Methionine o Domain Bacteria Prokaryotic Cell walls contain peptidoglycan Plasma membrane lipids are ester links between polar heads and fatty acid tails Has one 4 subunits RNA polymerase Initiator tRNA is Formylmethionine o Domain Eukarya Eukaryotic Cell walls lack peptidoglycan Fungus cell walls contain chitin Cellulose cell walls contain cellulose Plasma membrane lipids are ester links Has three 12 14 subunits each RNA polymerase Initiator tRNA is Methionine Definitions o Aerobic Bacteria Require oxygen o Anaerobic Bacteria Require low or zero oxygen environment o Facultative Aerobic Bacteria Like oxygen but may get by without it o Theory of Endosymbiosis Mitochondria resulted from the engulfment of aerobic bacteria Chloroplasts resulted from the engulfment of cyanobacteria o Protists Membrane bound organelles and DNA contained in a nucleus Most diverse group of organisms in terms of both structure and function Single celled eukaryotes Explain several reasons for why bacteria are important to the global ecosystem o Carbon Cycle Decomposition Respiration o Oxygen Cycle Photosynthesis Respiration o Nitrogen Cycle Nitrogen Fixation Describe two ways in which bacteria obtain energy o Heterotrophs Cannot make own food o Autotrophs Can make own food from light or chemicals How are cyanobacteria different from other bacteria o Important players in each of the main nutrient cycles and are photosynthetic o Cyanobacteria are important Nitrogen fixers and have specialized cells called heterocysts used in nitrogen fixation o May survive harsh environments through the production of spore like cells called akinetes o Understand describe the characteristics of each of the groups discussed in these notes o Group Diplomonadia Mainly parasitic 2 nuclei Diplo Multiple flagella No mitochondrial DNA or normal Krebs cycle Ex Giardia Intestinal Parasite o Group Parabasalia Symbionts and parasites 1 nucleus No plastids present No functional mitochondria Golgi complex associated with multiple flagella via parabasal fibers Ex Trichomonas vaginalis STD o Group Euglenozoa Many lifestyles 1 2 flagella containing a crystalline rod Two subgroups of euglenozoans Euglenids o 2 flagella originating from within an infolded structure o Most are photosynthetic o Ex Euglena o Kinetoplastids o Possess a single large mitochondria called a kinetoplast o Undulating membrane used for locomotion o Ex Trypanosoma Causes African Sleeping Sickness o o Group Alveolata Have membranous sacs underneath the cell membrane called alveoli Subgroups o Dinoflagellates 2 flagella in grooves Internal armor made of cellulose plates Important to ecological primary production or symbiotic such as with coral Some species are toxic Red tide Paralyiic Shellfish Poisoning o Apicomplexans Animal parasites Infectious stage is a cell called a sporozoite Possess a plastid celled an apicoplast Ex Plasmodium viviax Parasite that causes malaria o Ciliates Cillia used for locomotion and feeding Many have two nuclei Macronucleus o Metabolic function Micronucleus o Genetic DNA Reproduction Ex Paramecium o Group Stramenopila 2 flagella One Hairy and the other smooth May only be seen in reproductive cells Two subgroups Oomycetes Water Molds o Parasitic or saprophytic lives on dead matter or organic matter o Cell wall composed of cellulose o Structure celled an oogonia produces sessile egg nuclei o Ex Achyla Saprolegnia Potato Blight o Bacilariophytes Diatoms o Cell wall composed of hydrated silica plates o Carbohydrates stored as laminarin oils may also be stored o Uses Filtraton Nanotechnology o o Group Forams Filamentous pseudopodia extended outward through pores in a test shell for food engulfment Test composed of calcium carbonate o Group Radiolaria Filamentous pseudopodia radiate from a central point Test made of silica instead of calcium carbonate o Group Amoebozoa No test present Lobe shaped pseudopodia mobility and food capture Ex Amoeba
View Full Document
Unlocking...