Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Taxonomy • The study of the classification of living things • Taxa – group of one or more groups of organisms • SIX hierarchical levels of Increasing classification 1. 2. 3. 4. 5. 6. 7. 8. Domain Kingdom Phylum Class Order Family Genus Species similarity EUKARYA Most Inclusive ANIMAL CHORDATA MAMMALIA PRIMATES HOMINIDAE Increasing HOMO diversity SAPIENS Least Inclusive Binomial Nomenclature • Carolus Linnaeus (1700’s) • System for naming and classifying species • Two characteristics 1. Genus 2. Species • Used by all countries in all languages to avoid confusion among scientists. – Homo sapiens – Canus lupus – Felis domesticus Proper Way of Naming • Three ways to properly name and classify an organism 1. All Italics - capital letter of first name followed by lower case letter Tamiasciurus hudsonicus 2. Italics - capital letter followed by period (.) and then lower case letter italics T. hudsonicus 1. Handwritten - always underline the name Tamiasciurus hudsonicus Group organisms with increasing similarities Common Name Family Scientific Name Red squirrel Sciuridae Tamiasciurus hudsonicus Short-tail weasel Mustelidae Mustela erminea Groundhog Sciuridae Marnota monax Mink Mustelidae Mustela vison Eastern chipmunk Sciuridae Tamias striatus River otter Mustelidae Lutra canadensis Fisher Mustelidae Martes pennanti Muskrat Cricetidae Ondatra zibethica Black-footed ferret Mustelidae Mustela nigripes Dichotomous Key • Tool used by biologists to identify an unknown organism • Series of paired statements of anatomical description that leads to an identification. Key for Vertebrate Identification 1. a) animal has a spine…………………..go to 2 b) animal has no spine………..…invertebrate 2. a) animal has no gills and fins……..…. go to 3 b) animal has gills and fins…………….. Fish 3. a) animal has no scales…………..........go to 4 b) animal has scales………………..….reptile 4. a) animal has feathers …………………..bird b) animal has no feathers ……………..go to 5 5. a) animal has hair…………………….mammal b) animal has no hair………………..amphibian Three Domain Classification System • Based on – DNA analysis, Evolutionary history, Relationship among organisms Include 1. Bacteria (Prokaryotes) A. B. C. D. 2. Archaea (Prokaryotes) A. B. C. D. 3. Gram positive bacteria Spirochetes Chlamydia Cyanobacteria Extremeophiles Halophiles Methanogens Thermophiles Eukarya (Eukaryotes) A. B. C. D. Protista Fungi Plants Animals Major Features of The Three Domains Bacteria, Acrchaea, and Eukaryotes Feature Bacteria Archaea Eukaryotes Membrane-enclosed organelles Absent Absent Present Peptidoglycan in cell wall Present Absent Absent RNA polymerase One Type Several Kinds Several Kinds Introns (noncoding regions of genes) Absent Present in some genes Present Not inhibited Not inhibited Antibiotic sensitivity to streptomycin, Inhibited chloramphenicol Domain Bacteria • Lacks a nucleus and other membrane bound organelles • Contain ribosomes • Pili – hair like structures used to attach to other cells or objects • Flagellum – tail like extension for motorboating (propeller) • Cell wall • Nucleoid – chromosomal DNA • Plasmids – small circular pieces of DNA • Capsule – composed of polysaccharides, protects cell against phagocytosis Bacteria are Pathogens • • • • Klebsiella pneumoniae Clostridium difficile Escherichia coli Staphylococcus aureus – MRSA • Streptococcus pyogenes – Flesh eating disease Common Shapes of Prokaryotes • Coccus (Round) – N. meningitidis – meningitis • Bacillus (Rod) – B. anthracis - anthrax • Diplococci (Pair) – N. gonorrhoea – gonorrhoea • Streptococci (Chain) – S. pyogenes – scarlet fever • Spirochete (Spiral) – T. pallidum – syphilis Bacteria • Cell walls are composed of peptidoglycan • Reproduce Asexually via binary fission • Make energy using organic chemicals, inorganic chemicals, or photosynthesis • • • • Lack peptidoglycan in cell wall Reproduce via Binary Fission Live in extreme environments Methanogens – Live in environments that lack oxygen – Produce methane gas – Live in landfills • Extreme halophiles – Live in environments that love salt – Dead Sea, Great Salt Lake • Extreme thermophiles – Live in environments of extreme heat – Volcanic vents deep in the ocean Archaea Binary Fission • Asexual Reproduction Conjugation • Transfer of genetic material between bacterial cells • Creates genetic diversity • Antibiotic resistance Domain Eukarya • • • • Protista Fungi Plantae Animalia Animal-like Protists • Sporozoans – Cannot move on their own (nonmotile) – Reproduce both sexually (gametes) and asexually (mitosis) – Parasites – Transmitted through vectors (insects) • Plasmodium vivax – Causes malaria (most common) – Transmitted by female anopholes (mosquito) Plasmodium vivax • Mosquito bites – Infects human with sporozoites • Sporozoites infect liver cells – Develop into merozoites • Merozoites infect RBC’s – Continue to infect RBC’s – Some develop into gametocytes • Mosquito bites infected human – Gametocytes fertilize, develop into oocyst • Oocyst ruptures releasing sporozoites Plant-like Protists (Algae) • Eukaryotes • Cellulose cell walls • Use photosynthesis for energy (primary producers) • Produce molecular oxygen and organic compounds Plant-like protists • Dinoflagellates – Marine plankton (flagella) – Red tide • Algal blooms produce dinotoxins • Toxic to humans • Diatoms – Phytoplankton – Cell wall is made up silica • Euglenoids – Contain chloroplasts – Also feed by phagocytosis • Green Algae – Macroscopic seaweeds • Eukaryotes • Chitin cell walls • Use organic chemicals for energy (consumers/heterotrophs) • Decomposers (important in ecosystems) • Moulds – consist of masses of mycelia, which are composed of filaments called hyphae – Reproduce asexually (spores) • Yeasts – Round shape – Reproduce asexually (budding) Fungi Yeast Reproduction • Budding New organism develops from outgrowth on another cell at a particular site • Ascus Spore bearing cell in fungi Plantae (Eukaryotes) • All are autotrophic (make own food) – Synthesizing organic molecules using photosynthesis – Immobile • 10 divisions of plants • Characteristics of Plants include – Vascular tissue – Cone bearing – Flowering – Mosses, – Ferns Animalia (Eukaryotes) • • • • All are Heterotrophic Multicelluar Grouped into 35 phyla Most reproduce sexually (diploid stage) • Most species – sperm fertilizes egg • Monophyletic – All animal lineages can be traced back to a single common ancestor – Classified by anatomical features Classification of Animalia • Organisms are classified and identified using 6 characteristics 1. Structural – anatomy and physiology 2. Biochemical – enzymes, proteins, DNA 3. Cytological – cell structure 4. Embryological – development 5. Behavioral – patterns of actions 6. Fossil – common ancestor