Microbiology/immunology Exam 2 Part 2

Front 1

The greatest hindrance to germicidal activity of a chemical agent is
(A) The quality of the container
(B) The personnel performing the study
(C) The temperature
(D) The presence of organic matter

Back 1

(D) The presence of organic matter

Front 2

A strictly fermentative bacterium produces energy
(A) Only in the absence of oxygen
(B) By aerobic respiration only
(C) By fermentation or aerobic respiration
(D) By glycolysis only
(E) Only in the presence of oxygen

Back 2

(D) By glycolysis only

Front 3

The process of killing or removing all microorganisms in or on a material is termed:
(A) Sanitation
(B) Disinfection
(C) Antiseptic
(D) Sterilization

Back 3

(D) Sterilization

Front 4

Ethylene oxide is gas that
(A) Is used to sterilized food products
(B) Is safe to use on human skin
(C) Is used to sterilize large items such as hospital bed and other heat and moist sensitive items
(D) Is effective against all microbes except bacterial endospores and viruses

Back 4

(C) Is used to sterilize large items such as hospital bed and other heat and moist sensitive items

Front 5

Bacteria that spoil food in the refrigerator are most likely:
(A) mesophiles.
(B) psychrotrophs.
(C) thermophiles.
(D) psychrophiles.

Back 5

(D) psychrophiles.

Front 6

You inoculate two tubes of liquid culture media with 100 bacterial cells and incubate one tube at 20 degrees C and the other at 37 degrees C. After 48 hours, there are 798,000 bacteria/ml in the 20 degrees C tube and 2532 bacteria/ml in the 37 degrees C tube. You conclude that this species is a:
(A) halophile.
(B) mesophile.
(C) extremophile
(D) psychrophile.

Back 6

(D) psychrophile.

Front 7

The most common vector used for cloning gene is/are
(A) Bacteria
(B) Viruses
(C) Transposable elements
(D) None of these
(E) Plasmids

Back 7

(E) Plasmids

Front 8

The bacterial enzyme that cuts DNA at specific sites is called:
(A) Protease
(B) Polymerase
(C) Restriction enzyme
(D) Reverse transcriptase

Back 8

(C) Restriction enzyme

Front 9

Which of the following four stages of glucose oxidation requires molecular oxygen?
(A) Glycolysis
(B) Krebs cycle
(C) Oxidative phosphorylation
(D) Production of acetyl CoA

Back 9

(C) Oxidative phosphorylation

Front 10

Aerobic respiration differs from anaerobic respiration in which of the following respects?
(A) Aerobic respiration gets electrons from the Krebs cycle
(B) The final electron acceptors are different
(C) Anaerobic respiration is glycolysis
(D) Aerobic respiration requires the electron transport chain
(E) Anaerobic respiration produces more ATP

Back 10

(B) The final electron acceptors are different

Front 11

Liquid media containing heat-sensitive components such as vitamins would best be sterilized by:
(A) UV light radiation
(B) Membrane filtration
(C) Freeze-drying
(D) Lyophilization

Back 11

(B) Membrane filtration

Front 12

The Ti plamid is used as a vector to transfer DNA into
(A) Plants
(B) Viruses
(C) Animal cells
(D) Bacteria

Back 12

(A) Plants

Front 13

Which of the following treatments achieves sterilization?
(A) Pasteurization
(B) Boiling
(C) Commercial canning
(D) Autoclaving

Back 13

(D) Autoclaving

Front 14

During electron transport, excess amount of protons is transported into the cell
(A) False
(B) True

Back 14

(A) False
(out of the cell)

Front 15

Which of the following four stages of glucose oxidation produces the most ATP?
(A) glycolysis
(B) Krebs cycle
(C) Oxidative phosphorylation
(D) Production of acetyl CoA

Back 15

(C) Oxidative phosphorylation

Front 16

Which of the following is not different between RNA and DNA

(A) DNA and RNA are different in all of these cases
(B) Only RNA contains five-carbon sugar
(C) DNA had deoxyribose instead of ribose
(D) RNA has Uracil instead of Thymine
(E) RNA is single stranded

Back 16

(B) Only RNA contains five-carbon sugar

Front 17

Which molecule carries an anticodon?
(A) DNA
(B) mRNA
(C) tRNA
(D) Ribosome
(E) rRNA

Back 17

(C) tRNA

Front 18

Oxygen serves as final electron acceptor for
(A) Respiration
(B) Fermentation
(C) Photosynthesis
(D) Reduction

Back 18

(A) Respiration

Front 19

Which of the following is the best definition of oxidative phosphorylation?
(A) The transfer of a high-energy phosphate group to ADP
(B) The energy released in the reduction of carrier molecules is used to generate ATP
(C) The energy released as carrier molecules are oxidized is used to generate ATP
(D) Electrons are passed through a series of carriers to O

Back 19

(C) The energy released as carrier molecules are oxidized is used to generate ATP

Front 20

Reactions involving addition of electron or hydrogen atoms:
(A) Hydrolysis
(B) Phosphorylation
(C) Reduction
(D) Oxidation

Back 20

(C) Reduction

Front 21

How many molecules of ATP can be generated from the complete oxidation of glucose to CO2 and H2O?
(A) 2
(B) 38
(C) 4
(D) 34
(E) 76

Back 21

(B) 38

Front 22

Enzymes and reactions occurring at maximum possible rate:
(A) Facultative anaerobic growth condition
(B) Maximum growth temperature
(C) Thermophilic growth condition
(D) Minimum growth temperature
(E) Optimum growth temperature

Back 22

(E) Optimum growth temperature

Front 23

These are the sites of protein synthesis
(A) Ribosomes
(B) RNA
(C) DNA
(D) Nucleus
(E) mRNA

Back 23

(A) Ribosomes

Front 24

The most common vector used for cloning genes is:
(A) Plasmids
(B) Viruses
(C) Bacteria
(D) Ribosome

Back 24

(A) Plasmids

Front 25

A stop codon:
(A) Codes for the last amino acid
(B) Codes for no amino acid
(C) None of these
(D) Connects one protein to the next

Back 25

(B) Codes for no amino acid

Front 26

Salts and sugars work to preserve foods by creating a
(A) Hypertonic environment
(B) Depletion of nutrient
(C) Hypotonic environment
(D) Lower pH
(E) Lower osmotic pressure

Back 26

(A) Hypertonic environment

Front 27

The best definition of sterilization is the:
(A) Removal of Clostridium botulinum endospores.
(B) Elimination of bacteria.
(C) Removal of all microorganisms.
(D) Removal of unwanted microorganisms.

Back 27

(C) Removal of all microorganisms.

Front 28

Genetic change in bacteria can be brought about by
(A) Mutation.
(B) Transformation.
(C) Conjugation.
(D) Transduction.
(E) All of these

Back 28

(E) All of these

Front 29

During log phase, bacteria are:
(A) Dividing at the fastest possible rate.
(B) Dying and dividing in equal numbers.
(C) Dying exponentially.
(D) Preparing to divide.

Back 29

(A) Dividing at the fastest possible rate.

Front 30

Assume you are growing bacteria on a lipid medium that started at pH 7. The action of bacterial lipases should cause the pH of the medium to
(A) Increase
(B) Decrease
(C) Stay the same

Back 30

(B) Decrease

Front 31

Microbial growth is typically measured by increase in cell size
(A) False
(B) True

Back 31

(A) False

Front 32

Autotrophs use _____ as C source
(A) None of these
(B) Carbohydrates
(C) Organics
(D) Methane
(E) Carbon dioxide

Back 32

(E) Carbon dioxide

Front 33

This is used to screen for substances that might cause cancer
(A) Mutagenesis
(B) Carcinogenesis
(C) Ames test
(D) Frameshift mutation

Back 33

(C) Ames test

Front 34

Fatty acids are catabolized in
(A) Photosynthesis
(B) Glycolysis
(C) The electron transport chain
(D) The Krebs cycle

Back 34

(D) The Krebs cycle

Front 35

A population of bacterial cells carrying a desired plasmid
(A) Vector
(B) Clone
(C) Recombinant DNA
(D) Library

Back 35

(B) Clone

Front 36

Which of the following makes the most ATP:

(A) They all produce just about the same amount of ATP
(A) Oxidative phosphorylation
(C) Glycolysis
(D) Fermentation
(E) Substrate level phosphorylation

Back 36

(A) Oxidative phosphorylation

Front 37

The S-S medium agar inhibits growth of gram-positive bacteria. On this medium, bacteria that ferment lactose produce red colonies and bacteria that do not ferment lactose produce colorless colonies. This medium is
a. Selective
b. Differential
c. Synthetic (defined)
(A) A and c
(B) Only b
(C) Only a
(D) Both a and b
(E) a, b and c

Back 37

(D) Both a and b

Front 38

In transcription,
(A) DNA is changed to RNA
(B) DNA is copied to RNA
(C) Proteins are made
(D) DNA is replicated
(E) RNA is copied to DNA

Back 38

(B) DNA is copied to RNA

Front 39

Which of the following is best to sterilize heat-labile solutions?
(A) Membrane filtration
(B) Pasteurization
(C) Autoclave
(D) Dry heat

Back 39

(A) Membrane filtration

Front 40

The solidifying agent used most frequently in bacterial growth media is:
(A) Gelatin
(B) Peptone
(C) Agar
(D) Starch

Back 40

(C) Agar

Front 41

Recombinant DNA is produced when DNA from two different species are linked together;
(A) False
(B) True

Back 41

(B) True

Front 42

A DNA molecule containing fragments from two different sources

(A) Transformed DNA
(B) Recombinant DNA
(C) Plasmid
(D) Clone
(E) Vector

Back 42

(B) Recombinant DNA

Front 43

The genetic code is specific for each species
(A) True
(B) False

Back 43

(B) False

Front 44

If you grow E. coli in a glucose-minimal salts medium containing radioactively labeled nitrogen, the nitrogen will most likely be found in E. coli
(A) Waste products
(B) Enzymes.
(C) Plasma membrane.
(D) Carbohydrates.

Back 44

(B) Enzymes.

Front 45

Heritable change in DNA:
(A) Mutation
(B) Translation
(C) Termination
(D) Recombination

Back 45

(A) Mutation

Front 46

Reoxidation of NADH via electron transport chain allows protons to be pumped out. This process could result in:
(A) Production of high energy compounds
(B) All of these
(C) ATP formation
(D) None of these
(E) Oxidative phosphorylation

Back 46

(B) All of these

Front 47

All the following are true about substrate-level phosphorylation except
(A) It involves the direct transfer of a high-energy phosphate group from an intermediate metabolic compound to ADP
(B) The oxidation of intermediate metabolic compounds releases energy that is used to generate ATP
(C) It occurs in glycolysis
(D) No final electron acceptor is required

Back 47

(B) The oxidation of intermediate metabolic compounds releases energy that is used to generate ATP

Front 48

Which of the following treatments achieves sterilization?
a. Pasteurization
b. Autoclaving
c. Incineration
d. Dry oven
(A) b, c ,and d
(B) a, b, c
(C) b and d
(D) All of these
(E) c and d

Back 48

(A) b, c ,and d

Front 49

An experiment began with 4 cells and ended with 128 cells. How many generations did the cells go through?
(A) 32
(B) 6
(C) 4
(D) 5
(E) 64

Back 49

(D) 5

Front 50

A culture medium on which only gram-positive organisms grow and a yellow halo surrounds Staphylococcus aureus colonies is called a(n) A) Selective medium B) Differential medium C) Enrichment culture D) Defined medium
(A) b
(B) b and c
(C) a, b, and c
(D) a and b.
(E) a

Back 50

(D) a and b.

Front 51

Gamma rays kills microbe by producing highly reactive oxidizing molecules such as superoxides and free radicals
(A) True
(B) False

Back 51

(A) True

Front 52

Which of the following is a limitation of the autoclave?
(A) Length of time
(B) Ability to kill endospores
(C) Use with glassware
(D) Use with heat-labile materials
(E) Ability to inactivate viruses

Back 52

(D) Use with heat-labile materials

Front 53

Which of the following is the best definition of fermentation?
(A) The complete catabolism of glucose to CO2 and H2O
(B) The production of ethyl alcohol from glucose
(C) The production of energy by substrate-level phosphorylation
(D) The oxidation of glucose with organic molecules serving as electron acceptor
(E) The reduction of glucose to pyruvic acid

Back 53

(D) The oxidation of glucose with organic molecules serving as electron acceptor

Front 54

A quick microbiological test for potential carcinogens was developed by:
(A) Ames
(B) Watson and Crick
(C) Pasteur
(D) Koch
(E) Fleming

Back 54

(A) Ames

Front 55

GCCC is:
(A) Protein
(B) DNA
(C) Cannot tell as written
(D) RNA

Back 55

(C) Cannot tell as written

Front 56

Which of the following is not true about anaerobic respiration?
(A) It involves the Krebs cycle
(B) It generates ATP
(C) It involves glycolysis only
(D) It requires cytochromes
(E) It involves the reduction of nitrate

Back 56

(C) It involves glycolysis only

Front 57

Which of the following is not a sterilization method:
(A) Autoclave
(B) Pasteurization
(C) Membrane filtration
(D) Hot air oven

Back 57

(B) Pasteurization

Front 58

Which of the following pairs is mismatched?
(A) Transposase --- insertion of DNA segments into DNA
(B) DNA ligase --- joins segments of DNA
(C) DNA polymerase --- repair damage to DNA
(D) DNA polymerase --- makes a molecule of DNA from a DNA template
(E) RNA polymerase --- makes a molecule of RNA from an RNA template

Back 58

(E) RNA polymerase --- makes a molecule of RNA from an RNA template
(DNA template)

Front 59

Fastidious bacteria synthesize every complex molecules they need from the basic minerals
(A) True
(B) False

Back 59

(B) False
complex minerals

Front 60

The polymerase chain reaction, PCR, is used to:
(A) Polymerize amino acids
(B) Amplify RNA
(C) Synthesize protein
(D) Amplify sections of DNA

Back 60

(D) Amplify sections of DNA

Front 61

Turning anyway necessary, which is complementary to 5' AGGCUAAG 3'
(A) 5'CTTAGCCT3'
(B) 5'TCCGATTC5'
(C) 3'TAAGCTTA5'
(D) 5'TCCGATTG3'

Back 61

(A) 5'CTTAGCCT3'

Front 62

Differential media only allow certain bacteria to grow
(A) True
(B) False

Back 62

(B) False
(Selective media)

Front 63

Insertion of deletion of a single base pair could cause frameshift mutation
(A) True
(B) False

Back 63

(A) True

Front 64

Quaternary ammonium compounds are:
(A) None of these
(B) Strong disinfectant used to sterilize heavily contaminated hospital refuse
(C) Cationic detergents which help wash surfaces
(D) Very effective against endospores

Back 64

(C) Cationic detergents which help wash surfaces

Front 65

Which of the following affects the elimination of bacteria from an object?
(A) Presence of organic matter
(B) Number of bacteria present
(C) pH
(D) All of these
(E) Temperature

Back 65

(D) All of these

Front 66

Ultra violet light destroy bacteria by damaging its cell membrane
(A) False
(B) True

Back 66

(A) False

Front 67

Anaerobic respiration may use_____ as final electron acceptor
(A) Sulfate
(B) Carbonate
(C) All of these
(D) Nitrate
(E) None of these

Back 67

(C) All of these

Front 68

Restriction enzymes are
(A) Bacterial enzymes that destroy foreign DNA
(B) None of these
(C) Bacterial enzymes that splice DNA
(D) Eukaryotic enzymes that splice RNA
(E) Viral enzymes that destroy host DNA

Back 68

(A) Bacterial enzymes that destroy foreign DNA

Front 69

In the growth curve of a bacteria population, the bacteria are rapidly increasing in number in the:
(A) Log phase
(B) Lag phase
(C) Death phase
(D) Stationary phase

Back 69

(A) Log phase

Front 70

Biosynthetic reactions that require energy for the reaction to move forward are called:
(A) Exergonic reactions
(B) Catabolic reactions
(C) Endergonic reactions
(D) Anabolic reactions

Back 70

(C) Endergonic reactions

Front 71

Uses CO2 for carbon and H2 for energy.
(A) Photoautotroph
(B) Chemoheterotroph
(C) Photoheterotroph
(D) Chemoautotroph

Back 71

(D) Chemoautotroph

Front 72

The polymerase chain reaction is used to
(A) Produce long polymers of different molecules
(B) Produce proteins
(C) Amplify certain sections of DNA
(D) Amplify mRNA
(E) Reproduce bacteria cells

Back 72

(C) Amplify certain sections of DNA

Front 73

Multiple base changes such as substitution or addition can cause mutation
(A) True
(B) False

Back 73

(A) True

Front 74

Which of the following statements is false?
(A) DNA polymerase joins nucleotides in one direction only.
(B) The leading strand of DNA is made continuously.
(C) The lagging strand of DNA is started by an RNA primer.
(D) DNA replication proceeds in one direction around the bacterial chromosome.

Back 74

(D) DNA replication proceeds in one direction around the bacterial chromosome.

Front 75

The addition of which of the following to a culture medium will neutralize acids?
(A) pH
(B) Carbon
(C) Buffers
(D) Heat
(E) Sugars

Back 75

(C) Buffers

Front 76

Which one of these comprise of three distinct process of initiation, elongation and termination
(A) Replication
(B) Translation
(C) Recombination
(D) Transcription

Back 76

(B) Translation

Front 77

A gene is best defined as
(A) A sequence of nucleotides in RNA that codes for a functional product.
(B) A segment of DNA.
(C) Three nucleotides that code for an amino acid.
(D) A transcribed unit of DNA.
(E) A sequence of nucleotides in DNA that codes for a functional product.

Back 77

(E) A sequence of nucleotides in DNA that codes for a functional product.

Front 78

The mechanism by which genes are transferred into bacteria via viruses is called:
(A) Transduction
(B) Conjugation
(C) Mutation
(D) Transformation

Back 78

(A) Transduction

Front 79

Pasteurization
(A) is the use of heat to sterilize food products
(B) is the use of heat to reduce pathogenic/spoilage bacteria to a safe level
(C) is a process which uses intense cold to kill microorganisms
(D) is a process which uses short burst of radiation to kill microorganisms in food

Back 79

(B) is the use of heat to reduce pathogenic/spoilage bacteria to a safe level

Front 80

Which of the following is true of anabolism?
(A) Energy is not required, and water is used to break down complex organic molecues
(B) Energy is required, and complex organic compounds are broken down
(C) Energy is not required, and complex organic compounds are broken down
(D) Energy is not required, and complex organic compounds are synthesized
(E) Energy is required, and complex organic compounds are synthesized

Back 80

(E) Energy is required, and complex organic compounds are synthesized

Front 81

A bacteria growth medium could be
(A) Solid
(B) Differential
(C) All of these
(D) Selective
(E) Liquid

Back 81

(C) All of these

Front 82

The Ti plasmid is used as a vector to transfer DNA into
(A) Bacterial cells
(B) Plant cells
(C) Animal cells

Back 82

(B) Plant cells

Front 83

An enzyme that copies DNA to make a molecule of RNA.
(A) Transposase
(B) DNA ligase
(C) Restriction enzyme
(D) DNA polymerase
(E) RNA polymerase

Back 83

(E) RNA polymerase

Front 84

Ribosomes are composed of:
(A) DNA and RNA
(B) Lipid and Protein
(C) Protein and carbohydrate
(D) Lipid and carbohydrate
(E) Protein and RNA

Back 84

(E) Protein and RNA

Front 85

Uses glucose for carbon and energy.
(A) Photoautotroph
(B) Chemoheterotroph
(C) Photoheterotroph
(D) Chemoautotroph

Back 85

(B) Chemoheterotroph

Front 86

DNA is constructed of
(A) A single strand of nucleotides with internal hydrogen bonding.
(B) Nucleotides bonded A-C and G-T.
(C) Two strands of nucleotides running antiparallel
(D) Two strands of identical nucleotides with hydrogen bonds between them.

Back 86

(C) Two strands of nucleotides running antiparallel

Front 87

This RNA carries amino acid and brings it to the site of protein synthesis
(A) rRNA
(B) dsRNA
(C) tRNA
(D) ssRNA
(E) mRNA

Back 87

(C) tRNA

Front 88

Boiling is not reliable for sterilization because:
(A) Water boils at a higher temperature at lower altitudes
(B) Viruses are more sensitive to dry heat than to boiling
(C) Heat resistant endospores are unaffected
(D) Boiling does not kill Gram-negative bacteria

Back 88

(C) Heat resistant endospores are unaffected

Front 89

Which organism is not correctly matched to its energy source?
(A) Chemoautotroph ---NH3
(B) Chemoheterotroph --- glucose
(C) Photoheterotroph --- light
(D) Photoautotroph --- CO2
(E) Chemoautotroph --- Fe2+

Back 89

(D) Photoautotroph --- CO2

Front 90

A medium that contains lauryl sulfate inhibits growth of gram-positive bacteria. This medium is:
(A) Differential.
(B) Enriched.
(C) Both selective and differential
(E) Selective.

Back 90

(E) Selective.

Front 91

Lipid soluble or nonpolar molecules can enter membrane without the help of carriers
(A) True
(B) False

Back 91

(A) True

Front 92

A suffix used to describe a killing action would be:
(A) -tion
(B) -cidal
(C) -cillin
(D) -static

Back 92

(B) -cidal

Front 93

Which of the following organisms are resistant to destruction by typical control methods?
(A) Gram positive bacteria
(B) Bacterial endospores
(C) None of these
(D) Fungal spores

Back 93

(B) Bacterial endospores

Front 94

Agarose gel electrophoresis separates nucleic acid fragments according to
(A) Density
(B) Size
(C) Sequence
(D) Shape

Back 94

(B) Size

Front 95

Fermentation differs from anaerobic respiration in all of the following ways except which one? Fermentation doesn't:
(A) Require molecular oxygen
(B) Oxidize of NADH
(C) Require a final electron acceptor
(D) Oxidize of glucose

Back 95

(C) Require a final electron acceptor

Front 96

Operon
(A) All of these are correct for operon
(B) Exists in bacteria only
(C) Refers to a group of genes that are under one control
(D) Involves polycistronic mRNA

Back 96

(A) All of these are correct for operon

Front 97

You work for a chemical company and you are responsible for growing a bacterial culture that produces acetone. The bacteria are growing well in a glucose medium but are not producing acetone. The most likely reason is:
(A) The bacteria are dead
(B) The cells cannot use the glucose.
(C) The cells are fermenting the glucose.
(D) Molecular oxygen is in the medium

Back 97

(D) Molecular oxygen is in the medium

Front 98

According to the chemiosmotic mechanism, ATP is generated when
(A) A high-energy phosphate group is transferred from an intermediate metabolite to ADP
(B) Chlorophyll liberates an electron
(C) Protons are moved across a membrane
(D) Cells lyse in a hypotonic environment
(E) Electrons are transferred between carrier molecules

Back 98

(C) Protons are moved across a membrane

Front 99

In a typical bacteria growth curve, what phase follows lag and precedes stationary?
(A) Binary fission
(B) Death phase
(C) Stationary phase
(D) Log phase

Back 99

(D) Log phase

Front 100

An enzyme that cuts double-stranded DNA at specific nucleotide sequences.
(A) RNA polymerase
(B) DNA ligase
(C) Restriction enzyme
(D) DNA polymerase

Back 100

(C) Restriction enzyme

Front 101

You inoculate two tubes of liquid culture media with 100 bacterial cells and incubate one tube at 37 degrees C and the other at 55 degrees C. After 48 hours, there are 20,000 bacteria/ml in the 37 degrees C tube and 1,568,000 bacteria/ml in the 55 degrees C tube. You conclude that this species is a:
(A) mesophile.
(B) psychrophile.
(C) hyperthermophile.
(D) thermophile.

Back 101

(D) thermophile.

Front 102

Assume you are working for a chemical company and you are responsible for growing a yeast culture that produces ethyl alcohol. The yeasts are growing well on the maltose medium but are not producing alcohol. The most likely explanation is
(A) The maltose is toxic
(B) Yeasts don't produce ethyl alcohol
(C) O2 is in the medium
(D) Not enough protein is provided.

Back 102

(C) O2 is in the medium

Front 103

How many nucleotides are in a codon?
(A) Two
(B) Three
(C) Four
(D) One

Back 103

(B) Three

Front 104

Which of the following is not true about photophosphorylation?
(A) It requires CO2
(B) It occurs in photosynthesizing cells
(C) Light liberates an electron from chlorophyll
(D) The oxidation of carrier molecules releases energy
(E) Energy from oxidation reactions is used to generate ATP from ADP

Back 104

(A) It requires CO2

Front 105

Which of the following cannot be killed by autoclave?
(A) Organisms with thick cell walls
(B) Organisms with spores
(C) Pathogens
(D) Organisms with capsules
(E) All of these can be killed by autoclave

Back 105

(E) All of these can be killed by autoclave

Front 106

This is the intermediate process between DNA and protein synthesis. Generates mRNA, rRNA and tRNA
(A) Recombination
(B) Transcription
(C) Replication
(D) Translation

Back 106

(B) Transcription

Front 107

Heat kills microorganisms by
(A) Denaturing nucleic acids
(B) Irreversible coagulation of proteins
(C) Dissolving the capsule
(D) Destruction of carbohydrates in the cell wall

Back 107

(B) Irreversible coagulation of proteins

Front 108

This organism is killed by atmospheric O2.
(A) Obligate anaerobe
(B) Aerotolerant anaerobe
(C) Aerobe

Back 108

(A) Obligate anaerobe

Front 109

Mutation could be result of spontaneous error
(A) False
(B) True

Back 109

(B) True

Front 110

The readily usable energy currency in cell is:
(A) NADH
(B) ADP
(C) ATP
(D) NAD

Back 110

(C) ATP

Front 111

Generation time is the:
(A) Duration of lag phase
(B) Length of time it takes for a cell to divide
(C) Duration of log phase
(D) Minimum rate of doubling
(E) Time it takes for cell to mature

Back 111

(D) Minimum rate of doubling

Front 112

A cell that cannot make tRNA
(A) Can make proteins if mRNA is provided in the growth medium.
(B) Can't make proteins unless aminoacyl synthetase is provided in the growth medium.
(C) Can make proteins if amino acids are provided in the growth medium.
(D) Can't make proteins

Back 112

(D) Can't make proteins

Front 113

Bacteria death will result from damage to which of the following structure?
(A) Proteins
(B) All of these
(C) cell wall
(D) Nucleic acids
(E) cell membrane

Back 113

(B) All of these

Front 114

The damage caused by ultraviolet radiation is
(A) Never repaired.
(B) Repaired during transcription.
(C) Cut out and replaced
(D) Repaired during translation.
(E) Repaired by DNA replication.

Back 114

(C) Cut out and replaced

Front 115

The strand of DNA are bounded to one another by:

(A) Hydrophobic interaction
(B) Ionic bond
(C) Covalent bond
(D) Hydrogen bond
(E) Disulfide bridges

Back 115

(D) Hydrogen bond

Front 116

What is the difference between a disinfectant and an antiseptic?
(A) Disinfectants are used on environmental surfaces; antiseptics are used on living tissue.
(B) Disinfectants kill some microorganisms; antiseptics kill all microorganisms.
(C) Disinfectants remove all microorganisms; antiseptics remove some microorganisms.
(D) Disinfectants kill microorganisms; antiseptics inhibit microbial growth.

Back 116

A) Disinfectants are used on environmental surfaces; antiseptics are used on living tissue.

Front 117

Which of the following is not an end-product of fermentation?
(A) Acetone
(B) Glycerol
(C) Pyruvic acid
(D) Lactic acid
(E) Ethyl alcohol

Back 117

(C) Pyruvic acid

Front 118

The term facultative anaerobe refers to an organism that
(A) Requires less oxygen than is present in air
(B) Is killed by oxygen
(C) Uses oxygen or grows without oxygen
(D) Doesn't use oxygen but tolerates it
(E) Prefers to grow without oxygen

Back 118

(C) Uses oxygen or grows without oxygen

Front 119

Intense cold and freezing are very effective in killing bacteria
(A) True
(B) False

Back 119

(B) False

Front 120

This concentration of alcohol is the most effective bactericidal
(A) 40%
(B) 50%
(C) 70%
(D) 100%
(E) 30%

Back 120

(C) 70%

Front 121

Transformation is the transfer of DNA from a donor to a recipient cell
(A) By crossing over.
(B) By help of a virus
(C) By direct cell-to-cell contact
(D) By sexual reproduction
(E) Free DNA in the solution being picked up by the cell

Back 121

(E) Free DNA in the solution being picked up by the cell

Front 122

Which one of the following kills cells by damaging DNA?
(A) Alcohol
(B) Ultraviolet light
(C) Deep-freezing
(D) Pasteurization

Back 122

(B) Ultraviolet light

Front 123

Which of the following is not a product of transcription?
(A) mRNA
(B) tRNA
(C) A new strand of DNA
(D) rRNA

Back 123

(C) A new strand of DNA

Front 124

Segments of DNA capable of moving from one area in the DNA to another are called:
(A) Base analogs
(B) Okazaki fragments
(C) Transposons
(D) Restriction endonucleases

Back 124

(C) Transposons

Front 125

A culture medium consisting of agar, human blood, and beef heart is a
(A) Complex medium
(B) Selective medium
(C) Reducing medium
(D) Chemically defined medium
(E) Differential medium

Back 125

(A) Complex medium

Front 126

This process is needed to ensure that following generations acquire genetic material
(A) Replication
(B) Transcription
(C) Translation
(D) Recombination

Back 126

(A) Replication

Front 127

DNA polymerase is able to proof-read the DNA molecule
(A) False
(B) True

Back 127

(B) True

Front 128

Agarose gel electrophoresis separates nucleic acid fragments according to:
(A) Sequence
(B) Size
(C) Shape
(D) Density

Back 128

(B) Size