Mcb Exam 2

Front 1

in transcription

Back 1

dna is copied to rna

Front 2

_______ is used to make complementary DNA from an mRNA template

Back 2

reverse transcriptase

Front 3

which of the following enzymes cuts double-stranded DNA at specific nucleotide sequences?

Back 3

restriction enzyme

Front 4

which of these is NOT a required component of a PCR rxn?

Back 4

primase

Front 5

the sequence of 16S RNA of _______ are conserved among all cellular organisms

Back 5

ribosomes

Front 6

start codon?

Back 6

AUG

Front 7

a unicellular organism that has 70s ribosomes and a peptidoglycan cell wall is

Back 7

bacteria

Front 8

figure 2.1, if base 4 is guanine what is base 4'?

Back 8

cytosine

Front 9

figure 2.1, if base 4 is guanine what is base 11'?

Back 9

guanine

Front 10

in the sci name Mycobacterium lepromatosis, mycobacterium is the name of the

Back 10

genus

Front 11

during the time of _____ period, infectious virions are virtually undetectable inside the infected cell.

Back 11

eclipse

Front 12

which of the following is not a method for classifying and identifying bacteria?

Back 12

none of these (PCR, serological, biochem, differential staining)

Front 13

which of the following is not true about scientific nomenclature?

Back 13

names vary with geographical location

Front 14

which of the following organisms lacks nucleus and has a thin peptidoglycan wall surrounded by an outer membrane

Back 14

proteobacteria

Front 15

_____ is an obligate intracellular parasite in the alphaproteobacteria

Back 15

rickettsia

Front 16

borrelia burgdorferii is known as a spirochete because it ...

Back 16

has an axial filament

Front 17

actinomycetes are gram + bacteria and differ from filamentous fungi because actinomycetes

Back 17

do not have a membrane bounded nucleus

Front 18

which of the following bacteria is not gram +?

Back 18

vibrio cholerae

Front 19

mycoplasmas differ from other bacteria because they

Back 19

lack a cell wall

Front 20

e. coli belongs to

Back 20

gram negative bacteria

Front 21

the viral genome can be

Back 21

double stranded DNA/RNA, negative/positive single stranded RNA (all of these)

Front 22

which of the following is not a common method of amplifying animal viruses?

Back 22

in synthetic culture media

Front 23

which of the following statements about viruses is not true?

Back 23

viruses have their own catabolic enzymes to synthesize ATP

Front 24

which of the following enzymes can be found in the viral particles of retroviruses?

Back 24

reverse transcriptase

Front 25

which of the following steps does not occur during multiplication of an influenza virus?

Back 25

synthesis of viral DNA

Front 26

cytopathic effect (CPE) usually refers to changes in host cells due to _____

Back 26

viral infections

Front 27

which of the following is not an obligate intracellular parasite?

Back 27

none of these : chalmydia, influenza virus, rickettsia, bacteria phage

Front 28

which of the following viruses is associated with cervical cancer in women?

Back 28

human papillomavirus

Front 29

sequencing of 16s RNA is commonly used for classification and identification of bacteria

Back 29

true

Front 30

KSHV is essential but not sufficient for causing Kaposi's sarcoma

Back 30

true

Front 31

herpesviruses usually establish life long latency in their hosts

Back 31

true

Front 32

influenza virus has a segmented RNA genome

Back 32

true

Front 33

viral capsids are usually symmetric and made of repeating protein subunits

Back 33

true

Front 34

some people are naturally resistant to HIV infection because they have mutations in CCR5 gene which encodes an essential coreceptor of the virus

Back 34

true

Front 35

in bacteria, gene expression is typically regulated by means of operons

Back 35

true

Front 36

polioviruses are enteric and transmitted through oral-fecal route b/c their viral envelopes help them survive the acidic environment in stomach of their hosts

Back 36

false

Front 37

all viruses have lipid bilayer envelopes

Back 37

false

Front 38

the genomic RNA of negative strand RNA viruses can be infectious

Back 38

false

Front 39

which of the following statements concerning transcription is true

Back 39

all types of RNA in the cell are synthesized by transcription, which uses a portion of DNA as a template for copying

Front 40

which of the following best describes the flow of information in cells?

Back 40

mRNA is made by copying specific regions of DNA called genes. Ribosomes use mRNA as instructions, which provide a code specifiying the order of A.A. in the protein

Front 41

which of the following is an example of horizontal gene transfer in bacteria?

Back 41

transduction, conjugation and transformation

Front 42

which of the following is a method of vertical gene transmission?

Back 42

cell division

Front 43

Frederick Griffith did experiments on genetic transformation. Which of the following statements about his experiments is accurate?

Back 43

Griffith found that DNA released from dead (virulent) bacteria entered live (avirulent) bacteria and changed them genetically, causing them to become virulent.

Front 44

Which of the following does NOT accurately apply to the Ames test?

Back 44

The Ames test is based on the observation that reversions CANNOT occur in mutant bacteria.

Front 45

Deleting or inserting one nucleotide pair in the middle of a gene is an example of which of the following?

Back 45

frameshift mutation

Front 46

In the figure, which colonies are streptomycin-resistant and leucine-requiring?

Back 46

4 and 8

Front 47

Transformation is the transfer of DNA from a donor to a recipient cell

Back 47

as naked DNA in solution.

Front 48

Genetic change in bacteria can be brought about by

Back 48

transformation.
conjugation.
transduction.
mutation.
All of the answers are correct.

Front 49

t Which of the following statements regarding a bacterium that is R+ is false?

Back 49

It is F+.

Front 50

In the figure, if base 4 is thymine, what is base 4'?

Back 50

adenine

Front 51

In the figure, if base 4 is thymine, what is base 11'?

Back 51

thymine

Front 52

In the figure, base 2 is attached to

Back 52

deoxyribose.

Front 53

The necessary ingredients for DNA synthesis can be mixed together in a test tube. The DNA polymerase is from Thermus aquaticus, and the template is from a human cell. The DNA synthesized would be most similar to

Back 53

human DNA

Front 54

Amino Acids Encoded by the Human p53 Gene

Back 54

nonsense

Front 55

If you knew the sequence of nucleotides within a gene, which one of the following could you determine with the most accuracy?

Back 55

the primary structure of the protein

Front 56

Which statement best describes restriction enzymes?

Back 56

They are important for cloning applications because they can be used to cut DNA at specific nucleotide sequences.

Front 57

Which of the following pairings of recombinant DNA techniques and applications does NOT match?

Back 57

gene silencing: production of subunit vaccines

Front 58

Why is baker's yeast useful for expressing genetically engineered genes?

Back 58

Yeast cells are eukaryotic and so would likely be successful in expressing eukaryotic genes.

Front 59

Which of the following methods could be used to identify the source of an outbreak?

Back 59

DNA fingerprinting

Front 60

Which of the following statements about recombinant DNA technology is FALSE?

Back 60

It has limited application because genes of interest cannot be moved from one type of cell to another.

Front 61

Which of the following applications of recombinant DNA technology is NOT controversial?

Back 61

metagenomics

Front 62

Scientists like to use fluorescent proteins for various types of recombinant DNA procedures. You have a very small amount of the gene for a fluorescent protein. You'd like to make a fluorescent bacterium (!). Which of the following represents the correct sequence of procedures that you would use?

Back 62

Amplify the gene using PCR.
Insert the gene into a plasmid vector.
Transform the vector into the bacteria.

Front 63

Which statement regarding agricultural biotechnology is FALSE?

Back 63

Agricultural biotechnology is extremely limited because foreign genes cannot be inserted into plant cells.

Front 64

How many pieces will EcoRI produce from the plasmid shown in the figure?

Back 64

2

Front 65

The reaction catalyzed by reverse transcriptase is

Back 65

mRNA → cDNA.

Front 66

Which of the following is an advantage of using E. coli to make a human gene product?

Back 66

Its genes are well known.

Front 67

Biotechnology involves the

Back 67

use of microorganisms to make desired products, the use of animal cells to make vaccines, and the development of disease-resistanct crop plants.

Front 68

The Human Genome Project, which was completed in 2003, was focused on

Back 68

determining the nucleotide sequence of the entire human genome.

Front 69

Place the following steps in the PCR procedure in the correct order:
1) Incubate at 94°C to denature DNA strands;
2) Incubate at 72°C for DNA synthesis;
3) Incubate at 60°C for primer hybridization.

Back 69

1, 3, 2

Front 70

A source of heat-stable DNA polymerase is

Back 70

Thermus aquaticus.

Front 71

The Pap test for cervical cancer involves microscopic examination of cervical cells for cancerous cells. A new, rapid diagnostic test to detect human papilloma virus (HPV) DNA before cancer develops is done without microscopic exam. The steps involved in this FastHPV test are listed below. What is the second step?

Back 71

Add an RNA probe for HPV DNA.

Front 72

PCR can be used to identify an unknown bacterium because

Back 72

the RNA primer is specific.

Front 73

Restriction enzymes are

Back 73

bacterial enzymes that destroy phage DNA.

Front 74

Which statement regarding viral species is true?

Back 74

Viral species are not classified as part of any of the three domains.

Front 75

Numerical identification methods rely on a series of which kind of test to identify microorganisms?

Back 75

biochemical testing

Front 76

Consider a gram-negative human pathogen isolated from marine mammals. This pathogen is subjected to a series of tests and found to have the following characteristics: oxidase-positive; does not hydrolyze urea; produces indole; does not produce acetoin. Which of the following could it be?

Back 76

Pasteurella multocida

Front 77

Which technique is often used to determine the identity and abundance of microorganisms in an environment? (This technique is particularly useful because it does not require culture.)

Back 77

fluorescent in situ hybridization (FISH)

Front 78

Which of the following techniques could be used to identify antibodies produced by a patient?

Back 78

western blotting

Front 79

If two organisms have similar rRNA sequences, you can conclude that

Back 79

they evolved from a common ancestor.

Front 80

Which of the following is the best evidence for a three-domain system?

Back 80

Nucleotide sequences in ribosomal RNA vary between all three domains.

Front 81

Biochemical tests are used to determine

Back 81

enzymatic activities

Front 82

Which of the following is NOT based on nucleic-acid hybridization?

Back 82

Western blotting

Front 83

The phylogenetic classification of bacteria is based on

Back 83

rRNA sequences

Front 84

Which of the following statements is a reason for NOT classifying viruses in one of three
domains rather than in a fourth domain?

Back 84

Viruses are not composed of cells.

Front 85

Bacteria and Archaea are similar in which of the following?

Back 85

considered prokaryotic cells

Front 86

Serological testing is based on the fact that

Back 86

antibodies react specifically with an antigen.

Front 87

Nucleic acid hybridization is based on the fact that

Back 87

pairing between complementary bases occurs.

Front 88

Which of the following criteria is most useful in determining whether two organisms are related?

Back 88

both are gram positive

Front 89

In the figure, which figure shows the most closely related organisms?

Back 89

b

Front 90

You discovered a unicellular organism that lacks a nucleus and peptidoglycan. You suspect the organism is in the group

Back 90

archaea

Front 91

Into which group would you place a unicellular organism that has 70S ribosomes and a peptidoglycan cell wall?

Back 91

bacteria

Front 92

In the cladogram shown in the figure, which two organisms are most closely related?

Back 92

Micrococcus and Mycobacterium

Front 93

Which of the following characteristics indicates that two organisms are closely related?

Back 93

Both of their DNA can hybridize.

Front 94

Gram-positive organisms with low G + C content are commonly called __________.

Back 94

Firmicutes

Front 95

Which gammaproteobacteria are facultatively anaerobic, gram-negative rods that inhabit the intestinal tracts of humans and other animals?

Back 95

Enterobacteriales

Front 96

If a patient is diagnosed with a peptic ulcer, which genus of Proteobacteria is probably responsible?

Back 96

Helicobacter

Front 97

If a typhoid fever outbreak has occurred, which of the following statements is true?

Back 97

Salmonella is present, and the serovars may be differentiated by antigenic analysis.

Front 98

Regarding the order Rhizobiales of the class Alphaproteobacteria, which genus includes human pathogens?

Back 98

Brucella

Front 99

You have isolated a gram-positive bacterium with low G + C content. It was a contaminant in unpasteurized milk. It infected a pregnant woman, and now you are worried that her child will be stillborn. What bacterium is it?

Back 99

Listeria monocytogenes

Front 100

Which order or genus of Archaea are part of the microbiota of the human colon, vagina, and mouth?

Back 100

Methanobacteriales

Front 101

Blood agar would be the culture medium of choice if one were testing a patient for which of the following?

Back 101

scarlet fever

Front 102

Burkholderia was reclassified from the gammaproteobacteria to the betaproteobacteria because

Back 102

its rRNA sequence is similar to that of Neisseria.

Front 103

Thiobacillus oxidizes inorganic sulfur compounds and reduces CO2. This bacterium is a

Back 103

chemoautotroph.

Front 104

Salmonella, Shigella, Yersinia, and Serratia are all

Back 104

gram-negative facultatively anaerobic rods.

Front 105

Which of the following statements about the causative agent of Rocky Mountain spotted fever is FALSE?

Back 105

It is found in soil and water.

Front 106

Escherichia coli belongs to the

Back 106

proteobacteria.

Front 107

You have isolated a bacterium that grows in a medium containing only inorganic nutrients. Ammonia is oxidized to a nitrate ion. This bacterium is

Back 107

chemoautotroph

Front 108

Requirements for X and V factors are used to identify

Back 108

Haemophilus

Front 109

Rickettsias differ from chlamydias in that rickettsias

Back 109

require an arthropod for transmission.

Front 110

Which of the following is NOT an enteric?

Back 110

Campylobacter

Front 111

Which of the following are found primarily in the intestines of humans?

Back 111

facultatively anaerobic gram-negative rods

Front 112

Mycoplasmas differ from other bacteria in that they

Back 112

lack a cell wall

Front 113

Which one of the following does NOT belong with the others?

Back 113

Staphylococcus

Front 114

You have isolated an aerobic gram-positive, endospore-forming bacterium that grows well on nutrient agar. To which of the following groups does it most likely belong?

Back 114

bacillales

Front 115

Actinomycetes differ from fungi in that actinomycetes

Back 115

lack a membrane-bounded nucleus.

Front 116

Streptomyces differs from Actinomyces because Streptomyces

Back 116

is a strict aerobe.

Front 117

Which of the following is the best reason to classify Streptococcus in the Lactobacillales?

Back 117

rRNA sequences

Front 118

Which of the following bacteria are responsible for more infections and more different kinds of infections?

Back 118

Streptococcus

Front 119

Which of the following bacteria is gram-positive?

Back 119

Streptococcus

Front 120

Which of the following lacks a cell wall?

Back 120

Mycoplasma

Front 121

Staphylococcus and Streptococcus can be easily differentiated in a laboratory by which one of the following?

Back 121

growth in high salt concentrations

Front 122

Which of the following statements concerning viruses is true?

Back 122

The "host range" for a virus is determined by the presence or absence of particular components on the surface of a host cell that are required for the virus to attach.

Front 123

Which statement concerning viral structure is true?

Back 123

Spikes are found on some viruses. They are very consistent in structure and can be used for identification.

Front 124

Which of the following is true concerning a lysogenic viral replication cycle?

Back 124

During lysogeny, the viral genome integrates into the host DNA, becoming a physical part of the chromosome.

Front 125

Which of the following statements regarding latent viral infections is true?

Back 125

Latent infections can persist for years in an individual without causing any symptoms.

Front 126

Which of the following is true regarding cultivation and isolation of animal viruses?

Back 126

Diploid cell culture lines, developed from human embryos, are widely used for culturing viruses that require a human host.

Front 127

Which of the following statements concerning prion diseases is true?

Back 127

Normal host cellular prion proteins (PrPC) are converted into scrapie proteins (PrPSc).

Front 128

Which of the following is true of viroids?

Back 128

Viroids are short pieces of naked RNA.

Front 129

Viruses are the only known infectious agents that are obligatory intracellular parasites.

Back 129

False

Front 130

Which of the following statements about viruses is FALSE?

Back 130

Viruses use their own catabolic enzymes.

Front 131

Which of the following statements provides the most significant support for the idea that viruses are nonliving chemicals?

Back 131

They cannot reproduce themselves outside a host.

Front 132

How do all viruses differ from bacteria?

Back 132

Viruses are not composed of cells.

Front 133

A segmented genome can result in antigenic shift.

Back 133

True

Front 134

Helical and icosahedral are terms used to describe the shapes of a virus envelope.

Back 134

False

Front 135

What contributes to antigenic shift in influenza viruses?

Back 135

a segmented genome

Front 136

Which of the following is NOT used as a criterion to classify viruses?

Back 136

biochem tests

Front 137

Which of the following statements about viral spikes is FALSE?

Back 137

They are found only on nonenveloped viruses.

Front 138

Binomial nomenclature is used to name viruses.

Back 138

false

Front 139

DNA made from an RNA template will be incorporated into the virus capsid of

Back 139

Hepadnaviridae.

Front 140

Viruses that utilize reverse transcriptase belong to the virus families

Back 140

Hepadnaviridae and Retroviridae.

Front 141

A viral species is a group of viruses that

Back 141

has the same genetic information and ecological niche.

Front 142

Continuous cell lines differ from primary cell lines in that

Back 142

continuous cell lines can be maintained through an indefinite number of generations.

Front 143

A clear area against a confluent "lawn" of bacteria is called a

Back 143

plaque

Front 144

Which of the following is NOT utilized to culture viruses?

Back 144

culture media

Front 145

Most drugs that interfere with viral multiplication also interfere with host cell function.

Back 145

true

Front 146

Positive sense RNA strands of viruses are treated like mRNA inside the host cell.

Back 146

true

Front 147

Most RNA viruses carry which of the following enzymes?

Back 147

RNA-dependent RNA polymerase

Front 148

Which one of the following steps does NOT occur during multiplication of a picornavirus?

Back 148

synthesis of DNA

Front 149

The following steps occur during multiplication of retroviruses. Which is the fourth step?

Back 149

synthesis of double-stranded DNA

Front 150

Which of the following places these items in the correct order for DNA-virus replication?
1. Maturation
2. DNA synthesis
3. Transcription
4. Translation

Back 150

2; 3; 4; 1

Front 151

Generally, in an infection caused by a DNA-containing virus, the host animal cell supplies all of the following EXCEPT

Back 151

DNA polymerase.

Front 152

Bacteriophage replication differs from animal virus replication because only bacteriophage replication involves

Back 152

injection of naked nucleic acid into the host cell.

Front 153

Bacteriophages derive all of the following from the host cell EXCEPT

Back 153

lysozyme

Front 154

The mechanism whereby an enveloped virus leaves a host cell is called

Back 154

budding.

Front 155

Assume you have isolated an unknown virus. This virus has a single, positive sense strand of RNA, and possesses an envelope. To which group does it most likely belong?

Back 155

togavirus

Front 156

A viruss ability to infect an animal cell depends primarily upon the

Back 156

presence of receptor sites on the cell membrane.

Front 157

Which of the following statments is NOT true of lysogeny?

Back 157

It causes lysis of host cells.

Front 158

An envelope is acquired during which of the following steps?

Back 158

release

Front 159

Which of the following would be the first step in biosynthesis of a virus with a - (minus) strand of RNA?

Back 159

synthesis of double-stranded RNA from an RNA template

Front 160

Lysogeny can result in all of the following EXCEPT

Back 160

immunity to reinfection by any phage.

Front 161

Which of the following statements is FALSE?

Back 161

The prophage makes the host cell immune to infection by other phages.

Front 162

The definition of lysogeny is

Back 162

phage DNA is incorporated into host cell DNA.

Front 163

Oncogenic viruses

Back 163

cause tumors to develop.

Front 164

The most conclusive evidence that viruses cause cancers is provided by

Back 164

cancer following injection of cell-free filtrates.

Front 165

Assume a patient has influenza. During which time on the graph in the figure would the patient show the symptoms of the illness?

Back 165

HIGHEST PEAK

Front 166

Assume a patient had chickenpox (human herpesvirus 3) as a child. Which line on the graph in the figure would show the number of viruses present in this person as a 60-year-old with shingles (human herpesvirus 3)?

Back 166

last peak

Front 167

Some viruses, such as human herpesvirus 1, infect a cell without causing symptoms. These are called

Back 167

latent viruses.

Front 168

A lytic virus has infected a patient. Which of the following would best describe what is happening inside the patient?

Back 168

The virus is causing the death of the infected cells in the patient.

Front 169

An example of a latent viral infection is

Back 169

cold sores.

Front 170

A persistent infection is one in which

Back 170

the disease process occurs gradually over a long period.

Front 171

An infectious protein is a

Back 171

prion

Front 172

Which of the following is necessary for replication of a prion?

Back 172

PrPSc

Front 173

Which of the following prion diseases is found in deer and elk?

Back 173

Chronic wasting disease

Front 174

Which of the following prion diseases was also known as laughing disease?

Back 174

Kuru

Front 175

Which of the following conditions in humans is linked to bovine spongiform encephalopathy?

Back 175

Variant Creutzfeldt-Jakob disease

Front 176

What part of the nervous system is most affected by fatal familial insomnia?

Back 176

Thalamus

Front 177

Where does the name “scrapie” come from?

Back 177

The prion disorder causes infected sheep to scrape against objects until their skin is raw.

Front 178

Which of the following is most likely a product of an early gene?

Back 178

DNA polymerase

Front 179

Which virus is NOT associated with cancer?

Back 179

coronavirus

Front 180

Which statement is CORRECT concerning animal viruses?

Back 180

Retroviruses use an enzyme called reverse transcriptase, which synthesizes DNA by copying RNA.

Front 181

Which of the following is a human disease caused by prions?

Back 181

Creutzfeldt-Jakob disease (CJD)

Front 182

What are the three common means of horizontal gene transfer in bacteria (1 point) ?
Please explain each of them briefly (3 points).

Back 182

Conjugation is the transfer of genetic material between bacterial cells by direct cell-to-cell contact or by a bridge-like connection between two cells.
Transformation is a process in which cells directly uptake naked DNA from its surroundings.
Transduction is the process by which DNA is transferred from one Bacterium to another by viruses.

Front 183

Use 4 examples to explain applications of biotechnology in medicine and/or agriculture

Back 183

1) Transgenic plants (0.5 pt)
e.g. Pest resistance plants : Bacterial protein is toxic to insects, Clone Bt gene into crops. Expressed in leaves of plant, Kills only insects that feed on those crops (0.5 pt)
2) Use microbes to express genes, Produce eukaryotic proteins (0.5 pt) (enzyme) in large amounts
e.g. Human insulin, interferon (0.5 pt)
3) Use microbial gene products (0.5 pt), Microbes have widest diversity of enzymes
e.g. PCR depends on archaeal polymerases (0.5 pt)
4) Immunize against pathogens (HBV,HPV vaccine) (0.5 pt)
e.g. Use genes from pathogens (subunit vaccines) (0.5 pt) Without exposure to pathogenic organism
e.g. Nonpathogenic viruses carrying genes for pathogen's antigens as vaccines
5) Gene therapy (0.5 pt)to replace defective or missing genes (0.5 pt)

Front 184

Ti plasmid for making transgenic plants

Back 184

Agrobacterium tumfaciens,

Front 185

Peptic ulcer disease

Back 185

Helicobacter pylori,

Front 186

Opportunistic infections

Back 186

HIV/AIDS,

Front 187

Infectious mononucleosis (Kissing disease)

Back 187

EBV (Epstein-Barr virus),

Front 188

Chicken pox

Back 188

Herpesvirus,

Front 189

Genome replication involves reverse transcription

Back 189

Hepatitis B virus,

Front 190

Genome reassortment (antigenic shift)

Back 190

Influenza virus,

Front 191

Extra chromosomal self-replicating DNA

Back 191

Plasmid,