Deck 8: Microbial Genetics and Genetic Engineering

Question 1

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 nucleotides to the lagging strand
D)synthesizes an RNA primer
E)All of the choices are correct.

Answer 1

B

Question 2

Base pairs in DNA are held together by ________ bonds.

A)peptide
B)nonpolar covalent
C)polar covalent
D)hydrogen
E)sulfhydryl

Answer 2

D

Question 3

The site where the 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

Answer 3

E

Question 4

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

Question 5

Which is incorrect about purines?

A)Only found in DNA,not in RNA
B)Are nitrogenous bases
C)Always paired with a specific pyrimidine
D)Include adenine and guanine
E)Found within nucleotides

Question 6

The expression of genetic traits is the ________.

A)genome
B)genotype
C)proteome
D)phenotype
E)proteotype

Question 7

The DNA of microorganisms is made up of subunits called ________.

A)histones
B)amino acids
C)nucleotides
D)mRNA
E)polymerases

Question 8

Each nucleotide is composed of ________.

A)one phosphate,one nitrogenous base,and one sugar
B)one phosphate,one nitrogenous base,and two sugars
C)two phosphates,one nitrogenous base,and one sugar
D)two phosphates,one nitrogenous base,and two sugars
E)one phosphate,two nitrogenous bases,and one sugar

Question 9

Okazaki fragments are attached to the growing end of the lagging strand by ________.

A)DNA ligases
B)DNA polymerases
C)DNA helicases
D)DNA gyrases
E)primases

Question 10

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 pyrimidines
E)they are only present in the form of purines

Question 11

Among the microorganisms,various genomes can include ________.

A)chromosomes
B)plasmids
C)mitochondrial DNA
D)chloroplast DNA
E)All of the choices are correct.

Question 12

The duplication of a cell's DNA is called ________.

A)mitosis
B)replication
C)transcription
D)translation
E)mutation

Question 13

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 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.

Question 14

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

Question 15

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

Question 16

Eukaryotic chromosomes differ from bacterial 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

Question 17

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

A)chromosome
B)plasmid
C)prophage
D)genome
E)proteome

Question 18

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.

Question 19

Helicase ________.

A)supercoils DNA
B)unzips DNA
C)unwinds RNA
D)winds RNA
E)None of the choices are correct.

Question 20

The enzymes that can proofread replicating DNA,detect incorrect bases,excise them,and correctly replace them are ________.

A)DNA ligases
B)DNA polymerases
C)DNA helicases
D)DNA gyrases
E)primases

Question 21

DNA Polymerase III ________.

A)synthesizes primer
B)removes primer
C)joins Okazaki fragments
D)unzips the DNA helix
E)adds new bases and proofreads new DNA

Question 22

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

Question 23

All of the following pertain to transcription except ________.

A)occurs on a ribosome in the cytoplasm
B)occurs before translation
C)requires RNA polymerase
D)requires a template DNA strand
E)proceeds in the 5' to 3' direction of the growing mRNA molecule

Question 24

Which of the following is not associated with a bacterial ribosome?

A)Is a 70S
B)Has a peptide (P)site
C)Has an exit site
D)Small unit provides the enzymes for making peptide bonds
E)Has an amino acid (A)site

Question 25

A three base sequence on mRNA is called a(n)________.

A)codon
B)exon.
C)anticodon
D)intron

Question 26

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

Question 27

A sequence of bases on a eukaryotic gene that does not code for protein is called a(n)________.

A)promoter
B)operator
C)operon
D)exon
E)intron

Question 28

The following pertain to ribosomes during protein synthesis except ________.

A)they participate in both transcription and translation
B)they participate only in translation
C)they scans the mRNA for an AUG codon
D)they are composed of ribosomal RNA and protein
E)they shift to the right along the mRNA strand from one codon to the next

Question 29

Split genes ________.

A)are common in bacteria 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.

Question 30

For DNA replication,a primer of ________ is needed at the origin of nucleotide addition.

A)polymerase III
B)polymerase I
C)helicase
D)RNA
E)DNA

Question 31

Which 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

Question 32

DNA Polymerase I ________.

A)adds bases to new DNA chain
B)supercoils DNA
C)removes primers
D)unzips DNA
E)synthesizes RNA primer

Question 33

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

Question 34

Which of the following is incorrect about transfer RNA?

A)It has a bottom hairpin loop with an anticodon.
B)An anticodon is complementary to a codon.
C)It contains a binding site for an amino acid.
D)The initiator tRNA that binds to the P site has the anticodon UAC.
E)The initiator tRNA in bacteria carries tryptophan.

Question 35

Three consecutive bases in the DNA of a gene represent the code for one ________.

A)protein
B)nucleotide
C)amino acid
D)purine
E)pyrimidine

Question 36

Which of the following is incorrect about termination codons?

A)Where the bond between the final tRNA and the finished polypeptide chain is broken
B)Include AUG
C)Include UAA,UAG,and UGA
D)Do not have corresponding tRNA
E)Can also be called nonsense codons

Question 37

RNA molecules differ from DNA molecules because only RNA ________.

A)has ribose
B)has uracil
C)is typically one strand of nucleotides
D)does not have thymine
E)All of the choices are correct.

Question 38

Replication of DNA begins at a(n)________ rich area.

A)guanine-cytosine.
B)uracil-adenine.
C)adenine-thymine.
D)adenine-cytosine.
E)guanine-adenine.

Question 39

If the mRNA codon for alanine is GCA,then the correct anticodon would be ________.

A)GCA
B)CGT
C)ACG
D)CGU
E)UGC

Question 40

A permanent,inheritable change in the genetic information is called ________.

A)translation
B)transcription
C)mutation
D)alteration
E)regeneration

Question 41

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.

Question 42

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

Question 43

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

Question 44

The lactose repressor protein ________.

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.

Question 45

Which cell can transfer chromosomal and plasmid genes to a recipient cell by conjugation?

A)F⁺ cell
B)F⁻ cell
C)Hfr cell
D)R cell
E)B cell

Question 46

Synthesis of an inducible enzyme requires ________.

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.

Question 47

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

Question 48

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

Question 49

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 (stop)?

A)Missense
B)Nonsense
C)Insertion
D)Deletion
E)Silent

Question 50

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

Question 51

The gene that codes for a protein capable of repressing an operon is called the ________.

A)operator
B)structural locus
C)regulator
D)promoter
E)terminator

Question 52

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)a reaction of an Hfr cell
E)None of the choices are correct.

Question 53

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

Question 54

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

A)conjugation
B)transposons
C)transformation
D)transduction
E)transmission

Question 55

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

Question 56

Which of the following is not true of conjugation?

A)It involves direct contact between cells.
B)It transfers genes for drug resistance.
C)It transfers genes for resistance to heavy metals.
D)It transfers genes for a polysaccharide capsule.
E)The donor retains a copy of the transferred genes.

Question 57

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

Question 58

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

Question 59

The most serious type of mutation is a ________.

A)point mutation
B)silent mutation
C)frameshift mutation
D)back mutation
E)All the choices are equally serious

Question 60

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 taken up by a recipient cell
D)new progeny cells with genes from two parent bacterial cells
E)None of the choices are correct.

Question 61

DNA replication proceeds in one direction around the bacterial chromosome.

Question 62

DNA fragments can be separated in gel electrophoresis because ________.

A)nitrogenous bases have a net positive charge
B)nitrogenous bases have a net negative charge
C)phosphate groups have a net positive charge
D)phosphate groups have a net negative charge
E)None of the choices are correct

Question 63

Transcription occurs in the nucleus or at the nucleoid.

Question 64

Induced mutations result from errors in DNA replication.

Question 65

Repressible operons are normally turned on in the cell.

Question 66

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

Question 67

EcoRI and HindIII are ________.

A)palindromes
B)reverse transcriptase
C)restriction endonucleases
D)ligases
E)DNA polymerases

Question 68

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

Question 69

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

Question 70

DNA photolyase,in the presence of visible light,can repair DNA damage due to ultraviolet radiation.

Question 71

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

A)palindromes
B)reverse transcriptase
C)restriction endonucleases
D)ligases
E)DNA polymerases

Question 72

Lactose is a corepressor in the lac operon.

Question 73

In bacteria,initiator tRNA carries formyl methionine.

Question 74

Excised introns form structures called lariats.

Question 75

The smallest unit of heredity is a chromosome.

Question 76

All mutations are detrimental to the cell.

Question 77

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

A)palindromes
B)reverse transcriptase
C)restriction endonucleases
D)ligases
E)DNA polymerases

Question 78

Analysis of DNA fragments in gel electrophoresis involves ________.

A)larger fragments that move slowly and remain closer to the wells
B)DNA that has an overall negative charge and moves to the positive pole
C)DNA fragments that are stained to see them
D)an electric current through the gel that causes DNA fragments to migrate
E)All of the choices are correct

Question 79

DNA is denatured at ________.

A)37ᵒC
B)42ᵒC
C)60ᵒC
D)94ᵒC
E)100ᵒC

Question 80

Geneticists can make complimentary DNA from messenger,transfer,and ribosomal RNA by using ________.

A)palindromes
B)reverse transcriptase
C)restriction endonucleases
D)ligases
E)DNA polymerases