Pregunta 1
Pregunta
Which of the following is a macronutrient?
Respuesta
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Manganese
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Magnesium
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Zinc
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Cobalt
Pregunta 2
Pregunta
Denitrification is a process by which:
Respuesta
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Nitrogen gas is fixed by microorganisms
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Nitrates are reduced to nitrogen gas
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Nitrates are reduced to ammonia
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Nitrogen is assimilated into cellular material
Pregunta 3
Pregunta
Carl Woese of the University of Illinois and his collaborators identified two major branches of prokaryotic evolution. What was the basis for dividing prokaryotes into two domains?
Respuesta
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Microscopic examination of the staining characteristics of the cell wall
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Metabolic characteristics such as the production of methane gas
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Ecological characteristics such as the ability to survive extreme temperatures
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Molecular characteristics such as ribosomal RNA sequences
Pregunta 4
Pregunta
Catalase is indispensable to:
Respuesta
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Obligate anaerobes
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Aerotolerant anaerobes
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Aerobes
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All of the above
Pregunta 5
Pregunta
Addition of blood to a culture medium allows haemolytic bacteria to be picked out. This is an example of a:
Respuesta
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Selective medium
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Differential medium
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Synthetic medium
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Defined medium
Pregunta 6
Pregunta
Which of these environmental factors influence microbial growth?
Respuesta
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pH
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Water potential
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Oxygen
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All of the above
Pregunta 7
Respuesta
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Chemical modifications of DNA or RNA molecules
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Any changes of bacterial genome as compared with a wild type
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Events resulting from genetic exchange between bacterial plasmids
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Sequencing errors
Pregunta 8
Pregunta
A Wild-type bacterial strain is:
Respuesta
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A strain with a limited number of mutations
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An arbitrarily chosen strain
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A strain without plasmids
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A strain which is sensitive to antibiotics
Pregunta 9
Pregunta
Viruses may encode their genomes as:
Respuesta
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DNA
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RNA
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negative strand RNA
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All of the above
Pregunta 10
Pregunta
Virus particles:
Respuesta
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Are always smaller than bacterial cells
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Can replicate independently of a host cell if provided with a nutrient medium
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Can use some of the enzymes expressed in the host cell to aid their replication
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Are always eliminated by the host immune system
Pregunta 11
Pregunta
The symptom ‘chlorosis’ which develops when some fungi infect plants is due to:
Respuesta
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Cell death
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Nutrient imbalance
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Impaired photosynthesis
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Excess plant hormones
Pregunta 12
Pregunta
Which of the following is NOT a correct statement about true fungi:
Respuesta
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True fungi are eukaryotic
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All true fungi are multi-cellular
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True fungi are heterotrophic
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Most true fungi have chitin cell walls
Pregunta 13
Pregunta
The Bacille-Calmette-Guérin (BCG) vaccine is:
Respuesta
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Heat-killed Mycobacterium tuberculosis
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Attenuated live Mycobacterium tuberculosis
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Mycobacterium bovis
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Attenuated live Mycobacterium bovis
Pregunta 14
Pregunta
Which of the following is transmitted to humans by arthropods?
Respuesta
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Tuberculosis
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Malaria
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Cholera
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Typhoid
Pregunta 15
Pregunta
Pasteur is attributed with which one of the following discoveries?
Respuesta
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Was the first to see microorganisms under a microscope
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First to discover and use agar
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That there could be life without air
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The first chemical antibiotics
Pregunta 16
Pregunta
The length of a typical E. coli cell is approximately?
Pregunta 17
Pregunta
With respect to differences between members of the archaeal and bacterial domains/kingdoms, which is the CORRECT statement?
Respuesta
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Both have peptidoglycan in their cell walls
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Only some Archaea are capable of methanogenesis
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Archaea are sensitive to β-lactam antibiotics
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Bacteria have similar RNA polymerase to that of Archaea
Pregunta 18
Pregunta
Which statement is correct with respect to the E. coli chromosome?
Respuesta
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It is negatively supercoiled
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It is positively supercoiled
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There are typically several origins of replication
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It consists of over 50 million base pairs
Pregunta 19
Pregunta
A culture of E. coli is diluted by a factor of x 10-5 and, after plating out 100 μl on an agar plate, 78 colonies grew after incubation at 37oC overnight. The original culture therefore contained how many viable E. coli cells per ml?
Respuesta
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7.8 x 10(7)
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7.8 x 10(8)
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7.8 x 10(6)
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7.8 x 10(5)
Pregunta 20
Pregunta
Bacterial flagella bring about cell motion by which mechanism?
Respuesta
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Wave-like movement of the flagellum
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Rotation of the cell
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Rotation of the flagellum in one direction only
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Rotation of the flagellum that is reversible
Pregunta 21
Pregunta
Incorporation of atmospheric N2 to NH4+ occurs via the process of:
Pregunta 22
Pregunta
Active transport is necessary when:
Respuesta
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Diffusion will not allow adequate amounts of a substance to enter the cell
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Movement into the cell is against a concentration gradient
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The level of nutrients in nature is very low
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All of the above
Pregunta 23
Pregunta
The size of the most useful RNA molecule for prokaryotic evolutionary studies is:
Pregunta 24
Respuesta
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Act as a solvent for iron and transport iron into the cells
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Are a key component of cytochromes
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Help maintain osmotic balance in seawater microbes
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Develop when errors in membrane synthesis occur
Pregunta 25
Pregunta
Chemical energy is released when organic or inorganic compounds are:
Pregunta 26
Pregunta
MacConkey agar selects for:
Respuesta
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Gram-negative enteric bacteria
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Gram-positive bacteria
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Both Gram-positive and Gram-negative bacteria
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Haemolytic microorganisms
Pregunta 27
Pregunta
The Bacterial chromosome is:
Pregunta 28
Pregunta
With regards to bacterial plasmids which statement is the CORRECT one?
Respuesta
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Plasmids are extra chromosomal DNA that encode only resistance to antibiotics
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Plasmids are a part of the bacterial chromosome
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Plasmids are single stranded DNA found in some bacteria
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Plasmids are extra chromosomal DNA molecules
Pregunta 29
Pregunta
Which is the TRUE statement below:
Respuesta
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Viruses do not infect microorganisms
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All viruses are enveloped
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All viruses cause disease
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All viruses are parasites
Pregunta 30
Pregunta
The poliovirus mature virus particle:
Respuesta
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Contains 240 copies of a single protein
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Contains 60 copies of four proteins
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Has a dsDNA genome
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Has a single stranded negative–sense genome
Pregunta 31
Pregunta
Phytophthora infestans is a fungus-like organism which:
Pregunta 32
Pregunta
Zoophilic dermatophytes are:
Respuesta
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normally associated with animals and humans
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normally only associated with humans
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mainly associated with the soil
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mainly associated with contaminated water
Pregunta 33
Pregunta
Which of the following is primarily a respiratory pathogen?
Pregunta 34
Pregunta
Which of the following is NOT an acquired mechanism of antibiotic resistance in bacteria?
Respuesta
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Beta-lactamase production
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Efflux pump antibiotic export
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Lack of peptidoglycan
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RNA polymerase single nucleotide change
Pregunta 35
Pregunta
With regard to the differences between bacterial and eukaryotic cells which statement is the CORRECT one?
Respuesta
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Bacterial cells contain mitochondria
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Bacterial cells are usually larger than eukaryote cells
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Bacteria do not contain a chromosome
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Only bacterial cells are sensitive to β-lactam antibiotics
Pregunta 36
Pregunta
Koch’s postulates most correctly relate to which one of the following statements?
Respuesta
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The isolation of a bacterium in culture from a human alone indicates that it causes disease
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Determination in a series of logical steps the agent that causes disease
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The observation of bacterial cells in tissue from a human with disease indicates that the observed bacterium has caused the disease
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Inoculation of a bacterium into an animal to cause disease alone indicates that it is the cause of the disease observed
Pregunta 37
Pregunta
Which statement is CORRECT with respect to Lipopolysaccharide (LPS)?
Respuesta
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LPS is found in Gram positive cells
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LPS is found in Gram negative cells in the cytoplasmic membrane
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LPS is found in the outer-membrane of Gram negative cells.
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LPS is found inside all bacterial cells
Pregunta 38
Pregunta
A culture of E. coli is diluted by a factor of 10-6 and, after plating out 100 μl on an agar plate, 94 colonies grew after incubation at 37oC overnight. The original culture therefore contained how many viable E. coli cells per ml?
Respuesta
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9.4 x 10(7)
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9.4 x 10(8)
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9.4 x 10(6)
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9.4 x 10(5)
Pregunta 39
Pregunta
With respect to differences between members of the archaeal and bacterial domains/kingdoms, which is the CORRECT statement?
Respuesta
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Both have peptidoglycan in their cell walls
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Only some Archaea are capable of methanogenesis
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Archaea are sensitive to β-lactam antibiotics
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Bacteria have similar RNA polymerase to that of Archaea
Pregunta 40
Pregunta
Which statement is CORRECT with respect to peptidoglycan?
Respuesta
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There are multiple molecules of peptidoglycan in bacterial cell walls
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Only Gram positive cells possess peptidoglycan
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There is only a single molecule of peptidoglycan in a bacterial cell wall
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Peptidoglycan is only found in the Gram negative cell wall