Microbiology: Module 3 Flashcards

Which of the following is a serious concern when performing PCR?

A. high temperature needed may denature the DNA

B. restriction enzymes are difficult to obtain in adequate quantities

C. introduction and amplification of contaminating DNA

D. exposure to radiation by the lab personnel

E. it is a very time consuming process

Which is incorrect about purines?

A. Only found in DNA, not in RNA

B. Are nitrogenous bases

C. Always paired with a specific pyridimine

D. Include adenine and guanine

E. Found within nucleotides

Synthesis of a repressible enzyme is inhibited by

A. Repressor alone bound to operator

B. Substrate bound to repressor

C. Substrate bound to promoter

D. Corepressor and repressor binding to operator

E. None of the choices are correct

Which is incorrect about inducible operons?

A. Have genes turned off by a buildup of end product

B. Are often for catabolic pathways

C. Are normally turned off

D. Are turned on by the substrate of the enzyme

E. Include the lac operon

All of the following are desirable features in a microbial cloning host, except it

A. can be grown in large quantities

B. has a slow growth rate.

C. is capable of accepting plasmid vectors

D. will secrete a high yield of proteins from expressed foreign genes

E. has a genome that is well delineated

Labeled, known, short stretches of DNA used to detect a specific sequence of nucleotides in a mixture are

A. genetic engineering

B. biotechnology

C. recombinant DNA

D. gel electrophoresis

E. gene probes

The RNA molecules that carry amino acids to the ribosomes during protein synthesis are called

A. Ribosomal RNA

B. Messenger RNA

C. Transfer RNA

D. Primer RNA

E. Ribozymes

This is often used in forensic science to distinguish one sequence of DNA from another by comparing the sequence of the strands at specific loci:

A. cloning

B. gene therapy

C. antisense therapeutic

D. DNA fingerprinting

E. None of the choices are correct

The jumping of a gene from one location to another is done by

A. Conjugation

B. Transposons

C. Transformation

D. Transduction

E. Transmission

The lactose represor

A. is transcribed with the structural lac genes

B. is activated by binding lactose

C. is inactivated by binding lactose

D. requires lactose for its transcription

E. None of the choices are correct

Which cell can transfer the most DNA?

A. F+ cell

B. F- cell

C. Hfr cell

D. R cell

E. B cell

The following pertain to ribosomes during protein synthesis except

A. contain codons within their small subunit

B. Participate only translation

C. Bind to the 5' end of mRNA by their small subunit

D. Use their large subunit to supply enzymes for peptide bonding

E. Shift toward the 3' dnd of the mRNA strand from one codon to the next

The Southern Blot technique detects

A. DNA

B. RNA

C. proteins

D. recombinant DNA

E. specific genetic marker sequences on genes

Which of the following is not true of an organism's genotype?

A. is inherited

B. Are structural genes coding for proteins

C. Are genes coding for RNA

D. Are regulatory genes controlling gene expression

E. Are the expressed traits governed by the genes

All of the following are correct about DNA fingerprinting, except

A. it displays the unique pattern of an individual's DNA fragments.

B. it can be used to analyze evidence when only minute amounts of DNA are found.

C. it cannot be used on specimens older than five years.

D. it is routine to use it as trial evidence in the US

E. it can be used on hair and saliva

The process in which mutations are removed and the correct bases added is called

A. Transduction

B. Excision repair

C. Frameshift

D. Back-mutation

E. Transformation

When patient tissues are transferred with viruses carrying a needed, normal human gene, the technique is called

A. cloning

B. gene therapy

C. antisense therapeutic

D. DNA fingerprinting

E. None of the choices are correct

The Western Blot technique detects

A. DNA

B. RNA

C. proteins

D. recombinant DNA

E. specific genetic marker sequence on genes

All of the following pertain to nitrogenous bases except

A. Form pairs by hydrogen bonding

B. Guanine pairs with uracil

C. Adenine pairs with thymine

D. Cytosine and thymine are pyridimines

E. Allow variation from one nucleotide to another which creates the encoded information

The site where old DNA strands separate and new DNA strands will be synthesized is called the

A. Primer

B. Okazaki fragment

C. Template

D. Rolling circle

E. Replication fork

The most serious type of mutation is a

A. Point mutation

B. Silent mutation

C. Frameshift mutation

D. Back mutation

E. All choices are equally serious

The development of virulent, toxin-producing bacterial strains due to the presence of a temperate phage can occur in

A. Bacterial conjugation

B. Transformation

C. Generalized transduction

D. Specialized transduction

E. All of the choices are correct

A technique that separates a readable pattern of DNA fragments is

A. genetic engineering

B. biotechnology

C. recombinant DNA

D. gel electrophoresis

E. gene probes

The polymerase chain reaction (PCR) has been used in all of the following fields, except

A. forensics

B. evolutionary studies.

C. gene mapping.

D. medicine.

E. None of the choices; it is useful for all these fields.

Which of the following is incorrect about transfer RNA?

A. Has a bottom hairpin loop with an anticodon

B. An anticodon is complimentary to a codon

C. Contains a binding site for an amino acid

D. The initiator tRNA that binds to the P site has the anticodon UAC

E. Initiator tRNA in bacteria carries tryptophan

The antiparallel arrangement within DNA molecules refers to

A. Each base bonding at the 1' position of the sugar

B. A purine always bonding to a pyridimine

C. One helix strand that runs from the 5' to 3' direction and the other strand runs from the 3' to 5' direction.

D. An original parent DNA strand and one newly synthesized DNA strand comprising a new DNA molecule

E. None of the choices are correct

If the wild type DNA sequence reads THE CAT ATE THE BIG RAT, what type of mutation would change the sequence to THE CAT ATE THE BAG RAT?

A. Missense

B. Nonsense

C. Insertion

D. Deletion

E. Silent

Which of the following is not true of transposons?

A. Can change pigmentation

B. Can replace damaged DNA

C. Can transfer drug resistance

D. Can change the genome

E. Are always part of plasmids

Analysis of DNA fragments in gel electrophoresis is based on:

A. larger fragments move slowly and remain closer to the wells.

B. DNA has an overall negative charge and moves to the positive pole.

C. DNA fragments are stained to see them.

D. an electric current through the gel causes DNA fragments to migrate.

E. All of the choices are correct

Thermococcus litoralis and Thermus aquaticus are thermophilic bacteria that are

A. used as cloning vectors.

B. sources of heat stable DNA polymerases.

C. genetically engineered bacteria.

D. principal sources of restriction endonucleases.

E. None of the choices are correct.

Transgenic animals

A. can be engineered to become factories for manufacturing proteins.

B. are often obtained from germ line engineering

C. will pass the genes on to their offspring.

D. commonly include mice.

E. All of the choices are correct.

EcoRI an HindIII are

A. palindromes

B. reverse transcriptases

C. restriction endonucleases

D. ligases

E. DNA polymerases

DNA strands can be clipped crosswise at selected positions by using enzymes called

A. palindromes

B. reverse transcriptases

C. restriction endonucleases

D. ligases

E. DNA polymerases

A primer of ___ is needed at the origin of nucleotide addition.

A. Polymerase III

B. Polymerase I

C. Helicase

D. RNA

E. DNA

Both DNA sequencing and polymerase chain reactions require special ___ to initiate synthesis of a new DNA molecule.

A. RNA promoters

B. fluorescent nucleotides

C. primers

D. thermophilic polymerases

E. endonucleases

Semiconservative replication refers to

A. Each base bonding at the 1' position of the sugar

B. A purine always bonding to a pyrimidine

C. One helix strand that runs from the 5' to 3' direction and the other strand runs from the 3' to 5' direction

D. An original parent DNA strand and one newly synthesized DNA strand comprising a new DNA molecule

E. None of the choices are correct.

Which of the following methods determines which genes are actively transcribed in a cell under a variety of conditions?

A. DNA fingerprinting

B. microarray analysis

C. gene mapping

D. Western blot

E. antisense therapy

The transfer of DNA fragments from a dead cell to a live, competent recipient cell that results in a changed recipient cell is

A. Transduction

B. Conjugation

C. Transformation

D. Transmission

E. Mitosis

Split genes

A. Are common in prokaryotes and eukaryotes

B. Only have exons initially transcribed to mRNA

C. Have introns located only at the beginning and end of a coding region

D. Use spliceosomes to excise introns and then join exons

E. All of the choices are correct

The fluorescent in situ hybridization (FISH) probes are applied to intact cells and observed microscopically for the presence and location of

A. DNA

B. RNA

C. proteins

D. recombinant DNA

E. specific genetic marker sequence on genes

If the wild type DNA sequence reads THE CAT ATE THE BIG RAT, what type of mutation would change the sequence to THE CAT ATA ETH EBI GRA T?

A. Missense

B. Nonsense

C. Insertion

D. Deletion

E. Silent

Gene probes can be labeled for detection with

A. enzymes

B. fluorescent dyes

C. radioisotopes

D. All of the choices are correct

E. None of the choices are correct

The primers in PCR are

A. synthetic DNA oligonucleotides

B. bacterial enzymes

C. short RNA strands

D. DNA polymerases

E. reverse transcriptases

Helicase

A. Unwinds DNA

B. Supercoils DNA

C. Unwinds RNA

D. Winds RNA

E. None of the choices are correct

Of the following list, which antibiotics affect protein synthesis?

A. penicillin

B. tetracycline

C. chloramphenicol

D. ciprofloxacin

E. Both B and C

Geneticists can make complimentary DNA copies of messenger, transfer, and ribosomal RNA by using

A. palindromes

B. reverse transcriptases

C. restriction endonucleases

D. ligases

E. DNA polymerases

The DNA of microorganisms is made up of subunits called

A. Histones

B. Amino acids

C. Nucleotides

D. mRNA

E. Polymerases

The ___ is all of the genetic material of a cell.

A. Chromosome

B. Plasmid

C. Prophage

D. Genome

E. Proteome

In order to ensure compatibility between the target DNA and the plasmid DNA,

A. the target is removed from cells and isolated

B. cloning host is treated with calcium chloride and receives plasmid

C. target DNA and plasmid are treated with the same restriction endonuclease

D. desired protein is produced by cloning host

E. gene is amplified by multiplication of cloning host

The enzyme that can proofreads replicating DNA, detects incorrect bases, excises them, and correctly replaces them is

A. DNA ligase

B. DNA polymerase

C. DNA helicase

D. DNA gyrase

E. Primase

Which of the following is not true of conjugation?

A. Involves direct contact between cells

B. Transfers genes for drug resistance

C. Transfers genes for enzymes and adherence molecules

D. Transfers genes for a polysaccharide capsule

E. The donor retains a copy of the transferred genes

Which of the following is less subject to degradation than is chromosomal DNA and is used as an evolutionary time clock?

A. mitochondrial DNA

B. chloroplast DNA

C. rRNA

D. mRNA

E. tRNA

Repressible operons require that __ bind to the repressor protein before it can bind to the operator.

A. The product

B. A cofactor

C. A coenzyme

D. The substrate

E. The reactant

Which of the following additions have been made to principles of the central dogma of biology?

A. DNA information cannot be converted into RNA information

B. Protein information can be converted into DNA information

C. RNA can be used to regulate gene function

D. DNA codes for proteins

E. All of these

If you have the sequence ofmRNA that is AUAUGC, then the DNA antisense strand is __ .

A. AUAUGC

B. UAUACG

C. TATACG

D. CGUAUA

Bacterial conjugation involves

A. Bacteriophage carrying donor DNA to the recipient cell

B. A donor cell with a plasmid that synthesizes a pilus

C. Naked DNA fragments from a lysed donor cell are taken up by a recipient cell

D. New progeny cells with genes from two parent bacterial cells

E. None of the choices are correct

Each __ is a specific segment of the DNA with the code for production of one functional product.

A. Intron

B. Exon

C. Gene

D. Operator

E. Triplet

Which of the following is incorrect about termination codons?

A. Are also called nonsense codons

B. Where the bond between the final tRNA and the growing polypeptide is broken

C. Include AUG

D. Include UAA, UAG, UGA

E. Do not have corresponding tRNA

Structural genes code for

A. Ribosomal RNA molecules

B.Transfer RNA molecules

C. Cellular proteins

D. Gene expression elements

E. All of the choices are correct

DNA polymerase III

A. Is needed for adding nucleotides during mRNA synthesis

B. Synthesizes new DNA only in the 5' to 3' direction

C. Cannot add nueleotides to the lagging strand

D. Synthesizes an RNA primer

E. All of the choices are correct

A frameshift is caused by _ mutations?

A. Missense and insertion

B. Missense and nonsense

C. Nonsense and deletion

D. Deletion and insertion

E. Insertion and nonsense

The three-base sequence on DNA that codes for an amino acid is called a(n)

A. Codon

B. Exon

C. Anticodon

D. Intron

E. Triplet

Gene regulation can involve a protein repressor that blocks __ from initiating transcription.

A. DNA Polymerase I

B. DNA polymerase III

C. RNA polymerase

D. mRNA

E. rRNA

A sequence of bases on a gene that does not code for protein is called alan

A. Promoter

B. Operator

C. Operon

D. Exon

E. Intron

DNA Polymerase I

A. Removes primers

B. Adds bases to new DNA chain

C. Seals DNA gaps

D. Proofreads DNA chain

E. All of the choices are correct

A mutation that changes a normal codon to a stop codon is called a

A. Point mutation

B. Silent mutation

C. Back mutation

D. Missense mutation

E. Nonsense mutation

A nuc1eosome is a linear chromosome wound around the

A. Nuelear membrane

B. rRNA

C. mRNA

D. Histone

E. Nucleolus

A bacteriophage transfers DNA of the previous host to the current host. This is an example of

A. Conjugation

B. Generalized transduction

C. Specialized transduction

D. Creation of an Hfr cell

E. None of the choices are correct

During replication, each parent DNA strand serves as a __ for synthesis of new DNA strands.

A. Copy point

B. Template

C. Comparison molecule

D. Scaffold

E. Reservoir

Synthesis of an inducible enzyme requires

A. Repressor alone bound to operator

B. Substrate bound to repressor

C. Substrate bound to promoter

D. Co repressor and repressor binding to operator

E. None of the choices are correct

Which PCR step synthesizes complementary DNA strands?

A. add DNA polymerase and nucleotides at 72°C

B. cool DNA to between 50°C and 65°C

C. add primers

D. heat target DNA to 94°C

E. repeat the cycle of heating and cooling

Replication of DNA begins at a(n)

A. Guanine-cytosine rich area

B. Uracil-adenine rich area

C. Adenine-thymine rich area

D. Adenine-cytosine rich area

E. Guanine-adenine rich area

Hfr transfer involves all of the following except
A. Gene integration into the bacterial chromosome
B. Plasmid gene transfer
C. F factor is part ofthe F+ donor chromosome
D. High frequency transfer
E. A pilus connection between F+ and F- cells

If the wild type DNA sequence reads mE CAT ATE THE BIG RAT, what type of mutation would change the sequence to THE CAT ATE (stop)?

A. Missense

B. Nonsense

C. Insertion

D. Deletion

E. Silent

The gene of an operon that codes for a protein repressor is called the

A. Operator

B. Structural locus

C. Regulator

D. Promoter

E. None of the choices are correct

This molecule is synthesized as a copy of a gene on the DNA template strand

A. Ribosomal RNA

B. Messenger RNA

C. Transfer RNA

D. Primer RNA

E. Ribozymes

The deliberate removal of genetic material from one organism and combining it with the genetic material of another organism is a specific technique called

A. genetic engineering.

B. biotechnology.

C. recombinant DNA technology.

D. gel electrophoresis.

E. gene probes.

Each nucleotide is composed of

A. One phosphate, one nitrogenous base, one sugar

B. One phosphate, one nitrogenous base, two sugars

C. Two phosphates, one nitrogenous base, one sugar

D. Two phosphates, one nitrogenous base, two sugars

E. One phosphate, two nitrogenous bases, one sugar

RNA polymerase binds to the

A. Start codon

B. Termination sequence

C. Regulation sequence

D. Promoter sequence

E. None of the choices are correct

In Griffith's experiments with S tr ep t ococ c us p n e um o nia e, rough non-encapsulated Streptococci were converted into smooth encapsulated Streptococci in the presence
of the heat- killed smooth encapsulated Streptococci. What is the tenn that describes this process?

A. transduction

B. conjugation

C. transformation

D. cloning

Among the microorganisms, various genomes can include

A. Chromosomes

B. Plasmids

C. Mitochondrial DNA

D. Chloroplast DNA

E. All of the choices are correct

Groups of three consecutive bases along the DNA of a gene have the code for one

A. Protein

B. Nucleotide

C. Amino acid

D. Purine

E. None of the choices are correct

The enzyme_ adds three nucleotides of DNA in the _direction when DNA is being semi-conservatively replicated

A. DNA polymerase III, 3'->5'

B. DNA polymerase I, 3'->5'

C. DNA polymerase III, 5'->3'

D. DNA polymerase I, 5'->3'

E. None of the above

Amplification of DNA is accomplished by

A. polymerase chain reaction.

B. DNA seque

C. gene prob

D. Southern blot.

E. All of the choices are correct.

Which of the following drugs is/are produced by genetic engineering and approved for human use?

A. human growth hormone

B. Factor VIII

C. insulin

D. tissue plasminogen activator

E. All of the choices are correct.

The expression of genetic traits is the

A. Genome

B. Genotype

C. Proteome

D. Phenotype

E. Proteotype

The nontranscribed region of DNA to which RNA polymerase binds to initiate transcription is called the

A. Promoter

B. Operator

C. Operon

D. Exon

E. Intron

Which step involves transformation?

A. target DNA removed from cells and isolated

B. cloning host takes up a plasmid

C. target DNA and plasmid treated with the same restriction endonuclease

D. desired protein is produced by cloning host

E. gene is amplified by multiplication of cloning host

The use of an organism's biochemical processes to create a product is

A. genetic engineering.

B. biotechnology.

C. recombinant DNA.

D. gel electrophoresis

E. gel probes

Base pairs in DNA are held together by __ bonds.

A. Peptide

B. Non polar covalent

C. Polar covalent

D. Hydrogen

E. Sulfhydryl

Recombinant strains of this organism are released to colonize plant roots to produce an insecticide to destroy invading insects:

A. Esc h e ri chia col i

B. Saccha r omyces cer e v i s iae

C. T h e rmu s aq uati c us

D. Pseudomo na s sy r i n g a e

E. P se udo m o n as f lu o r escens

All of the following are characteristics that make plasmids good cloning vectors, exc ep t

A. they are small.

B. they are well characterize

C. they can be transferred into appropriate host cells.

D. they can carry genetic markers, such as antibiotic resistance genes.

E. they can accept a relatively large amount of foreign DNA.

The various techniques by which scientists manipulate DNA in the lab are called

A. genetic engineering.

B. biotechnology.

C. recombinant DNA.

D. gel electrophoresis.

E. gene probes.

Full induction of the lactose operon requires

A. Lactose present

B. Lactose and glucose present

C. Lactose present without glucose

D. Lactose and arabinose present

E. All of the choices induce the lactose operon

DNA Polymerase III

A. Synthesizes primer

B. Removes primer

C. Joins Okazaki fragments

D. Unzips the DNA helix

E. Proofreads new DNA

When DNA is heated to just below boiling (90°C - 95°C),

A. the sugar phosphate backbone of the DNA strands br

B. the sugar, phosphate and base come apart in each nucleotide.

C. the helix unwinds but hydrogen bonds between the bases remain intact.

D. the two DNA strands separate completelY

E. Nothing happens until the boiling point is reached (100°C).

What type of mutation alters the base, but not the amino acid being coded for?

A. Silent

B. Back

C. Point

D. Nonsense

E. Missense

Which PCR step causes the denaturation of double-stranded DNA?

A add DNA polymerase and nucleotides at 72degC
B. cool DNA to between 50degC and 65degC
C. add primers
D. heat target DNA to 94degC
E. repeat the cycle of heating and cooling

Sequences of DNA that are identical when read from 5' to 3' direction on one strand and the 3' to 5' direction on the other strand are

A. palindromes

B. reverse transcriptases

C. restriction endonucleases

D. ligases

E. DNA polymerases

Eukaryotic chromosomes differ from prokaryotic chromosomes because only eukaryotes have

A. Histone proteins

B. Chromosomes in a nucleus

C. Several to many chromosomes

D. Elongated, not circular, chromosomes

E. All of the choices are correct