BioSc221/325 Exam 1 Name ______________________________Multiple choice. (2 point each) Choose the one best answer to each of the following questions.____ Fossilized stromatolites, which provide a geological record of early microorganisms, were formed fromA. layers of decayed marine animals that were degraded by microorganismsB. layers of decayed marine plants that were degraded by microorganismsC. microbial mats, layers of microbial communitiesD. chemicals that formed during the early earth that came together to form the first microorganisms____ In general, prokaryotic cells are __.A. larger than eukaryotic cellsB. smaller than eukaryotic cellsC. about the same size a eukaryotic cellsD. not physiologically comparable to eukaryotic cells and therefore proaryotic and eukaryotic cell sizes should not be compared.____ The three domains of life areprokaryotes, eukaryotes, eubacteriaprotists, plants, animalsplants, animals, monerabacteria, archaea, eukarya____ Enzyme found in tears that cleaves the -1,4 linkage of the peptidoglycan layer.A. lysozymeB. mureinC. penicillinD. vancomycin____ Bacteriophage lambda has provided a wealth of information for biologists interested in how microorganisms make “decisions” because lambda “decides” betweeninfecting Escherichia coli or Salmonella typhimuriuma lytic or lysogenic life cyclelysing its host cell or budding from the host cell membraneforming a plaque or a colony_____ Antiviral drug therapy ideally should target viral activities that are unique to the virus. One of these targets is the process or attachment. A fairly new anti-influenza drug targets _____ a protein on the surface of the influenza virus which is associated with the attachment process. A. influenza capsomer proteinB. pilinC. neuraminidaseD. porin____ An organism requiring many growth factors and only grows on a complexmedium is described asA. finickyB. selectiveC. facultativeD. fastidious____Archaea acquired their name because they were thought to be ancient in the fact that they resemble some of the earliest microorganisms. That is because these organisms live in ___ conditions which resemble the conditions on early earth.A. anoxicB. high temperatureC. high salineD. All of the aboveE. None of the above____ A bacterial cell which has lost its peptidoglycan layer but remains intact is called a(n)A. lysozomeB. protoplastC. periplasmD. osmoplast____ Proteins that form channels in the outer membranes of gram-negative bacteria.A. bactoprenolsB. lipoproteinsC. porinsD. transport proteins____ Attachment is an essential step for pathogenic bacteria to infect their host. Many bacteria have long filamentous protein structures that aid in this process. These structures are calledA. porinsB. piliC. receptorsD. teichoic acids____ AZT is an antiviral drug used to treat patients with HIV infections. Although this nucleotide analog can also be harmful to the host cell machinery it is effective because _____, an enzyme that is unique to HIV, preferentially tries to use AZT over the normal nucleotides.A. reverse transcriptaseB. DNA polymeraseC. RNA polymeraseD. ligase____ Molecules found in halophiles that protect them from the low water activity of their environment.A. compatible solutesB. halitesC. halogensD. isotoners____ Microscopes that are designed to enhance the contrast between cells and their surrounding medium are calledA. bright fieldB. dark-fieldC. phase contrastD. epifluorescent____ Methanogenic archaea are prokaryotic organisms that are found in anoxic conditions and only use molecules with one carbon as their carbon source. Which of the following describes the conditions for an enrichment culture for methanogenic archaea from the human colon?A. Carbon dioxide, hydrogen, oxygen freeB. Carbon dioxide, oxygen richC. Glucose, oxygen freeD. Glucose, oxygen rich____ Lipopolysaccharide (LPS) is associated with __ .A. the outer membrane of Gram-positive bacteria.B. the outer membrane of Gram-negative bacteria.C. the cytoplasmic membrane of Gram-positive bacteria.D. the cytoplasmic membrane of Gram-negative bacteria.____ The objective lenses of modern light microscopes are described as compound lenses because they consist of several lenses of different shapes (convex or concave) and different glass. The purpose of these compound lenses is to A. correct spherical and chromatic aberrationsB. increase resolving powerC. extend the length of the lens to get closer to the sampleD. to match the optical properties of the microscope slide, coverslip and immersion oil____ Form of oxygen that is toxic to living organismsA. hydrogen peroxideB. singlet oxygenC. superoxideD. none of the aboveE. all of the above____ Electron microscopes are used to visual bacterial subcellular structures. The ability to resolve such small structures is achieved throughthe short wavelength of electronsthe ability to get the lenses of the electron microscope very close to the samplethat high intensity of the electron beamall of the abovenone of the above____ When doing a colony count __.A. It is assumed that each colony arose from only one organism.B. Only viable cells are countedC. The medium must be suitable for colonial growthD. All of the above____ The bacterial “cannibal” Bdevolovibrio bacteriovorans” moves toward its prey by responding to chemical signals.. This type of movement is described asA. random walkB. brownian motionC. chemiosmosisD. chemotaxis____ Enveloped viruses exit their host cell by a process calledA. lysisB. lysogenyC. extractionD. buddingMatching. (1 point each) Match the definition in the left column with the appropriate term in the right column. Note, not all terms will be used.____ Molecule found in the cell wall of Gram-positive but not Gram-negative bacteria.____ Associated child-bed fever with medical students not washing their hands after surgery.____ The first to use an epidemiological approach to solving a disease outbreak (cholera).____ Identified the causative agents of the deadly diseases anthrax and tuberculosis____ Cocci arranged in "grape-like" clusters.____ A culture technique in which conditions favor the growth of the desired type of organism.____ A device for enumerating microorganisms by microscope instead of cultivation.____ Bacteria that remain blue after completion of the Gram stain procedure.____ Technique that makes it possible to separate large genome size DNA fragments on a gel.A. EnrichmentB. Gram-negativeC. Gram-positiveD. Koch, RobertE.