UARK Microbiology Exam 1 Question and Answers

UARK Microbiology Exam 1 Question and Answers Cell Theory All living things are composed of cells Anton van Leewenhoek Observed the first microbes with a microscope he designed Robert Hooke Reported that living things are composed of cells The first life on Earth Ancestors of bacteria The first microbes were observed in 1673 Father of microbiology Louis Pasteur How to make an augur plate 121 C for 15 - 20 minutes under 18 psi Scientific Method 1. Observe some aspect of the universe 2. Create a hypothesis 3. Experiments 4. Create a theory 5. Law Microbiology the study of organisms to small to be seen with the naked eye Bacteria is everywhere Ubiquity of bacteria Microbes include Bacteria, fungi, protozoa, microscopic algae, and viruses Pathogenic Disease-causing Microbes produce chemical products such as Ethanol, acetone, and vitamins Microbes produce fermented food such as vinegar, cheese, and bread Microbe-produced manufacturing product Cellulase Microbe-produced disease treatment product Insulin The study of bacteria Bacteriology The study of fungi Mycology The study of viruses Virology The study of algae Algology The study of protozoans Protozoology Parasitology The study of protozoa and parasitic worms Rebecca Lancefield Discovered differences in the chemical composition of a polysaccaride in the cell walls of many pathogenic streptococci Three discoveries of Pasteur Fermentation, pasteurization, and biogenesis Lister revolutionized surgery by developing aseptic techniques, he used phenol Linnaeus created the nomenclature (method of naming) of organisms Jenner developed the first vaccine (smallpox) Bassi discovered a fungus that caused disease in silkworms and deduced that human diseases are caused by other living microorganisms Koch provided evidence (along with Pasteur) for the germ theory (states that some diseases are caused by microorganisms), discovered that pure cultures allow pure isolation of a microbe, discovered that Mycobacterium tuberculosis is a pathogenic bacteria that causes tuberculosis, discovered that Vibro cholerae is the microorganism that causes cholera Neisser discovered Neisseria gonorrhoeae was a pathogenic strain of bacteria that caused gonorrhea Finlay determined yellow fever was transmitted through mosquitos Hess developed agar as a medium for culturing microorganisms Metchnikoff the first to discover phagocytosis, a cell-mediated immune response to foreign matter. Gram developed the gram-staining method (differentiates bacteria by the chemical and physical properties of their cell walls) Escherich discovered Escherichia coli (E. coli) that is a common bacteria found in the digestive systems of warm-blooded animals, some strains can cause food poisoning Kitasato co-discoverer of the infectious agent of bubonic plague (Clostridium tetani) Ehrlich developed the theory of immunity (explain the immune response in living cells), syphilis Fleming, Chain, Florey Penicillin Griffith Transformation in bacteria Lancefield Streptococcal antigens Lederberg and Tatum Bacterial conjugation The golden age of microbiology ; beginning with Pasteur's work, discoveries included the relationship between microbes and disease, immunity, and antimicrobial drugs Pasteur showed that microbes are responsible for fermentation Fermentation the microbial conversion of sugar to alcohol in the absence of air Bacteria that use air spoil wine by turning it to vinegar (acetic acid) Pasteurization The application of a high heat for a short time to kill harmful bacteria in beverages Spontaneous Generation The hypothesis that life arises from nonliving matter; a "vital force" is necessary for life Biogenesis The hypothesis that living cells arise only from preexisting cells Pasteur Provided the basis for aseptic techniques First pasteurization of grape juice 1869 Koch's Postulates 1. The same pathogen must be resent in every case of the disease 2. The pathogen must be isolated from the diseased host and grown in pure culture 3. The pathogen from the pure culture must cause the disease when it is inoculated into a healthy, susceptible laboratory animal 4. The pathogen must be isolated from the inoculated animal and must be shown to be the original organism Exceptions to Koch's Postulates 1. Viruses, many rickettsias, Treponema pallidum (syhilis), and Mycobacterium leprae (leprosy) do not grow on artificial media 2. Humans as the only test host, ethical issues, ex. HIV The germ theory of disease Koch proved that a bacterium causes anthrax and provided the experimental steps, Koch's postulates, to prove that a specific microbe causes a specific disease Vaccination immunity, Jener inoculated a person with cowpox virus, who was then protected from smallpox Fleming Discovered the first antibiotic Fleming observed that Penicillium fungus made an antibiotic, penicillin, that killed S. aureus Staph antibiotic resistant Staph causes nosomial (hospital-inquired) infections Types of microorganisms Bacteria, Archaea, Fungi, Protozoa, Algae, Viruses, and multicellular animal "parasites" Developed the three domains Woese in 1978 The three domains are based on Sequences in rRNA The three domains Eukarya, Bacteria, and Archaea Eukarya Animals, plants, and fungi 3 types of archaea Methanogens, extreme halophiles, and hyperthermophiles Archaea that emit methane anaerobically Methanogens Archaea that can withstand high saltiness Extreme halophiles Archaea that can withstand high temperatures Hyperthemermophiles Archaea Prokaryotes; lack peptidoglycan cell walls; often live in extreme environments Prokaryotes "Prenucleus"; one circular chromosome, not in a membrance, no histones, no organelles, bacteria (peptidoglycan walls), archae (pseudomurein cell walls), divides binary fission Bacteria Single-celled; peptidoglycan walls; divide by binary fission, derive nutrition from inorganic or organic chemicals or photosynthesis Eukaryote Paired chromosomes, in nuclear membrane; histones, organells, polysaccaride celll walls, when present, divides by mitosis Most bacteria are Monomorphic (single shape) Few bacteria are Pleomorphic (many shape) Fungi Eukaryotes (distinct nucleus), chitin cell walls, obsorb organic chemicals for energy Yeasts are Unicellular Molds and mushrooms Multicellular Molds consist of Masses of mycelia, which are composed of filaments called hyphae Carlos Linnaeus Established the system of scientific nomenclature Each organism has two names Genus and specific epithet Scientific Names Are italicized or underlined; the genus is capitalized and the specific epithet is lowercase Normal microbiota Microbes normally present in and on the human body; prevent growth of pathogens; produce growth factors such as vitamin B and K Resistance The ability of the body to ward of disease Resistance factors include Skin, stomach acid, and antimicrobial chemicals Biofilms Microbes attach to solid surfaces such as rocks, pipes, teeth, and medical implants and grow in masses; they can cause infections and are often resistant to antibiotics Parts of a prokaryotic cell Pillus, cytoplasm, 70s ribosomes, plasma membrane, nucleoid containing DNA, inclusions, plasmid, fimbria, capsule, cell wall, plasma membrane Bacterial cell pairs Diplococci, diplobacilli Bacterial cell Clusters Staphylococci Bacterial cell chains Streptococci, Streptobacilli Bacterial cell groups of four Tetrads Bacterial cell cubelike group of eight Sarcinae Bacteria shaped like small bananas Vibrio Bacteria shaped like a short spiral Spirillum Bacteria shaped like a long spiral Spirochete Other unique bacterial shapes Star shaped and rectangular shaped Rod-shaped bacteria Bacillus Spherical-shaped bacteria Coccus Spiral-shaped bacteria Spirillum, vibrio, spirochete