Quiz
Microorganisms MCQ's 2012
Create a free account to finish this quiz
Save your progress and see your final score.
Already have an account? Sign in
Questions in this quiz (40)
1Which of the following is a macronutrient?
- AManganese
- BMagnesium
- CZinc
- DCobalt
2Denitrification is a process by which:
- ANitrogen gas is fixed by microorganisms
- BNitrates are reduced to nitrogen gas
- CNitrates are reduced to ammonia
- DNitrogen is assimilated into cellular material
3Carl 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?
- AMicroscopic examination of the staining characteristics of the cell wall
- BMetabolic characteristics such as the production of methane gas
- CEcological characteristics such as the ability to survive extreme temperatures
- DMolecular characteristics such as ribosomal RNA sequences
- AMicroscopic examination of the staining characteristics of the cell wall
4Catalase is indispensable to:
- AObligate anaerobes
- BAerotolerant anaerobes
- CAerobes
- DAll of the above
5Addition of blood to a culture medium allows haemolytic bacteria to be picked out. This is an example of a:
- ASelective medium
- BDifferential medium
- CSynthetic medium
- DDefined medium
6Which of these environmental factors influence microbial growth?
- ApH
- BWater potential
- COxygen
- DAll of the above
7Mutations are:
- AChemical modifications of DNA or RNA molecules
- BAny changes of bacterial genome as compared with a wild type
- CEvents resulting from genetic exchange between bacterial plasmids
- DSequencing errors
8A Wild-type bacterial strain is:
- AA strain with a limited number of mutations
- BAn arbitrarily chosen strain
- CA strain without plasmids
- DA strain which is sensitive to antibiotics
9Viruses may encode their genomes as:
- ADNA
- BRNA
- Cnegative strand RNA
- DAll of the above
10Virus particles:
- AAre always smaller than bacterial cells
- BCan replicate independently of a host cell if provided with a nutrient medium
- CCan use some of the enzymes expressed in the host cell to aid their replication
- DAre always eliminated by the host immune system
11The symptom ‘chlorosis’ which develops when some fungi infect plants is due to:
- ACell death
- BNutrient imbalance
- CImpaired photosynthesis
- DExcess plant hormones
12Which of the following is NOT a correct statement about true fungi:
- ATrue fungi are eukaryotic
- BAll true fungi are multi-cellular
- CTrue fungi are heterotrophic
- DMost true fungi have chitin cell walls
13The Bacille-Calmette-Guérin (BCG) vaccine is:
- AHeat-killed Mycobacterium tuberculosis
- BAttenuated live Mycobacterium tuberculosis
- CMycobacterium bovis
- DAttenuated live Mycobacterium bovis
14Which of the following is transmitted to humans by arthropods?
- ATuberculosis
- BMalaria
- CCholera
- DTyphoid
15Pasteur is attributed with which one of the following discoveries?
- AWas the first to see microorganisms under a microscope
- BFirst to discover and use agar
- CThat there could be life without air
- DThe first chemical antibiotics
16The length of a typical E. coli cell is approximately?
- A20 μm
- B2 μm
- C200 nm
- D20 nm
17With respect to differences between members of the archaeal and bacterial domains/kingdoms, which is the CORRECT statement?
- ABoth have peptidoglycan in their cell walls
- BOnly some Archaea are capable of methanogenesis
- CArchaea are sensitive to β-lactam antibiotics
- DBacteria have similar RNA polymerase to that of Archaea
18Which statement is correct with respect to the E. coli chromosome?
- AIt is negatively supercoiled
- BIt is positively supercoiled
- CThere are typically several origins of replication
- DIt consists of over 50 million base pairs
19A 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?
- A7.8 x 10(7)
- B7.8 x 10(8)
- C7.8 x 10(6)
- D7.8 x 10(5)
20Bacterial flagella bring about cell motion by which mechanism?
- AWave-like movement of the flagellum
- BRotation of the cell
- CRotation of the flagellum in one direction only
- DRotation of the flagellum that is reversible
21Incorporation of atmospheric N2 to NH4+ occurs via the process of:
- ANitrogen fixation
- BNitrification
- CDenitrification
- DNone of the above, atmospheric N2 cannot be incorporated into NH4+.
22Active transport is necessary when:
- ADiffusion will not allow adequate amounts of a substance to enter the cell
- BMovement into the cell is against a concentration gradient
- CThe level of nutrients in nature is very low
- DAll of the above
23The size of the most useful RNA molecule for prokaryotic evolutionary studies is:
- A5S
- B16S
- C18S
- D23S
24Siderophores:
- AAct as a solvent for iron and transport iron into the cells
- BAre a key component of cytochromes
- CHelp maintain osmotic balance in seawater microbes
- DDevelop when errors in membrane synthesis occur
25Chemical energy is released when organic or inorganic compounds are:
- AReduced
- BIncorporated into larger molecules
- CSynthesized
- DOxidized
26MacConkey agar selects for:
- AGram-negative enteric bacteria
- BGram-positive bacteria
- CBoth Gram-positive and Gram-negative bacteria
- DHaemolytic microorganisms
27The Bacterial chromosome is:
- ACircular DNA
- BLinear DNA
- CEither circular or linear DNA
- DDouble stranded RNA
28With regards to bacterial plasmids which statement is the CORRECT one?
- APlasmids are extra chromosomal DNA that encode only resistance to antibiotics
- BPlasmids are a part of the bacterial chromosome
- CPlasmids are single stranded DNA found in some bacteria
- DPlasmids are extra chromosomal DNA molecules
29Which is the TRUE statement below:
- AViruses do not infect microorganisms
- BAll viruses are enveloped
- CAll viruses cause disease
- DAll viruses are parasites
30The poliovirus mature virus particle:
- AContains 240 copies of a single protein
- BContains 60 copies of four proteins
- CHas a dsDNA genome
- DHas a single stranded negative–sense genome
31Phytophthora infestans is a fungus-like organism which:
- ACauses disease of a wide range of woody hosts
- BCauses potato blight
- CCauses ringworm
- DCauses black sigatoka disease of banana
32Zoophilic dermatophytes are:
- Anormally associated with animals and humans
- Bnormally only associated with humans
- Cmainly associated with the soil
- Dmainly associated with contaminated water
33Which of the following is primarily a respiratory pathogen?
- AVibrio cholerae
- BMycobacterium tuberculosis
- CSalmonella typhi
- DMycobacterium leprae
34Which of the following is NOT an acquired mechanism of antibiotic resistance in bacteria?
- ABeta-lactamase production
- BEfflux pump antibiotic export
- CLack of peptidoglycan
- DRNA polymerase single nucleotide change
35With regard to the differences between bacterial and eukaryotic cells which statement is the CORRECT one?
- ABacterial cells contain mitochondria
- BBacterial cells are usually larger than eukaryote cells
- CBacteria do not contain a chromosome
- DOnly bacterial cells are sensitive to β-lactam antibiotics
36Koch’s postulates most correctly relate to which one of the following statements?
- AThe isolation of a bacterium in culture from a human alone indicates that it causes disease
- BDetermination in a series of logical steps the agent that causes disease
- CThe observation of bacterial cells in tissue from a human with disease indicates that the observed bacterium has caused the disease
- DInoculation of a bacterium into an animal to cause disease alone indicates that it is the cause of the disease observed
37Which statement is CORRECT with respect to Lipopolysaccharide (LPS)?
- ALPS is found in Gram positive cells
- BLPS is found in Gram negative cells in the cytoplasmic membrane
- CLPS is found in the outer-membrane of Gram negative cells.
- DLPS is found inside all bacterial cells
38A 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?
- A9.4 x 10(7)
- B9.4 x 10(8)
- C9.4 x 10(6)
- D9.4 x 10(5)
39With respect to differences between members of the archaeal and bacterial domains/kingdoms, which is the CORRECT statement?
- ABoth have peptidoglycan in their cell walls
- BOnly some Archaea are capable of methanogenesis
- CArchaea are sensitive to β-lactam antibiotics
- DBacteria have similar RNA polymerase to that of Archaea
40Which statement is CORRECT with respect to peptidoglycan?
- AThere are multiple molecules of peptidoglycan in bacterial cell walls
- BOnly Gram positive cells possess peptidoglycan
- CThere is only a single molecule of peptidoglycan in a bacterial cell wall
- DPeptidoglycan is only found in the Gram negative cell wall
Information
- Description
- Papers covered; May 2012 NO RESIT PAPER
- Author
- tj.sloan
- Language
- English
- Views
- 48
- Rating
- No ratings yet Rate this quiz