Deck 13: Bacterial Genome Replication and Expression

Question 1

The __________ is the collection of characteristics of an organism that an investigator observes.

Answer 1

pheype

Question 2

Proteins that recognize unfolded polypeptides and help them fold into their proper conformations are called ______________.

Answer 2

chaperones

Question 3

Aminoacyl-tRNA synthetases catalyze covalent addition of __________ __________ to tRNAs.

Answer 3

amino acids

Question 4

Which of the following is true about the structure of DNA?

A)Purine and pyrimidine bases are attached to the 1'-carbon of the deoxyribose sugars.
B)Purine and pyrimidine bases are joined by phosphodiester bonds.
C)Adjacent bases are stacked on top of each other,one base pair every 0.34 nm.
D)all of the choices

Question 5

The __________ describes the specific set of genes an organism possesses.

Question 6

A consensus sequence in the untranslated leader sequence of a prokaryotic mRNA which serves as a ribosome binding site is called the __________ sequence.

Question 7

The two strands of a DNA molecule are __________; that is,they are oriented in opposite directions.

Question 8

As prokaryotes normally only have one set of genes,they are called __________.

Question 9

On mRNA molecules,a nontranslated sequence called the ___________ usually precedes the initiation codon.

Question 10

Which of the following is not a complementary base pair usually found in DNA molecules?

A)adenine-thymine
B)guanine-cytosine
C)adenine-uracil
D)all of the choices

Question 11

The principle of transformation was first demonstrated by which of the following individuals or groups of individuals?

A)Avery,MacLeod,and McCarty
B)Griffith
C)Hershey and Chase
D)Watson and Crick

Question 12

The genetic information in DNA is divided into units called

A)proteins.
B)genes.
C)genotype.
D)phenotype.

Question 13

Messenger RNA molecules that direct the synthesis of more than one polypeptide are said to be __________.

Question 14

DNA functions as a storage molecule,holding genetic information for the lifetime of a cellular organism and allowing that information to be duplicated and passed on to its progeny.

Question 15

The basic differences between RNA and DNA reside in their sugar and pyrimidine bases; RNA has ribose and uracil whereas DNA has deoxyribose and thymine.

Question 16

Which of the following is not a pyrimidine?

A)adenine
B)cytosine
C)thymine
D)uracil

Question 17

mRNA molecules have a nontranslated sequence called the __________,which is located downstream of the termination codon.

Question 18

Hershey and Chase demonstrated that when the bacteriophage T2 infected its host cell,the __________ is injected into the host but the __________ remained outside.

Question 19

Which of the following individuals or groups of individuals demonstrated that the transforming principle was DNA?

A)Avery,MacLeod,and McCarty
B)Griffith
C)Hershey and Chase
D)Watson and Crick

Question 20

The B form of the DNA double helix contains a wider major groove and a narrower minor groove because the two polynucleotide strands are not positioned directly opposite one another in the helical cylinder.

Question 21

Which of the following is not considered the final product of the expression of a gene?

A)A polypeptide chain.
B)An mRNA molecule.
C)A tRNA molecule.
D)An rRNA molecule.

Question 22

Bacterial chromosomes,unlike eukaryotic chromosomes,often consist of a single replicon.

Question 23

Which of the following is in the coding region of a gene?

A)promoter
B)leader
C)trailer
D)none of the choices

Question 24

The transcribed,but not translated,sequence that is immediately upstream of the region that encodes the functional product is called the __________ region.

A)leader
B)promoter
C)coding
D)trailer

Question 25

DNA replication is a complex process,and as a result the frequency of error is quite high.

Question 26

Over twisting or under twisting of helical DNA generates

A)hypertwists.
B)hypotwists.
C)hypercoils.
D)supercoils.

Question 27

Each chromosome has one or more __________ site(s)where replication begins.

A)promoter
B)replicon
C)origin
D)bifurcate

Question 28

The transcribed and translated region of a gene is the __________ region.

A)leader
B)promoter
C)coding
D)trailer

Question 29

A section of DNA that codes for a protein or other functional product is called a(n)

A)codon.
B)gene.
C)replicon.
D)anticodon.

Question 30

The region at which the RNA polymerase binds is the __________ region.

A)leader
B)promoter
C)coding
D)trailer

Question 31

The unexpressed regions of split genes are called

A)exons.
B)endons.
C)introns.
D)codons.

Question 32

The Y-shaped part of the DNA molecule where the actual replication process occurs is called the replication __________.

A)tongue
B)fork
C)junction
D)splice

Question 33

The strand of DNA for a particular gene that is copied by the RNA polymerase to form mRNA is called the __________ strand.

A)leading
B)template
C)transcription
D)copy

Question 34

The chromosomes of most bacteria are comprised of

A)double-stranded circular molecules.
B)double-stranded linear molecules.
C)single-stranded circular molecules.
D)single-stranded linear molecules.

Question 35

During replication the 2 strands of the DNA molecule are unwound from one another by enzymes called

A)ligases.
B)unwindases.
C)helicases.
D)primases.

Question 36

A bacterial __________ is the nontranscribed region of the DNA to which RNA polymerase binds in order to initiate transcription.

A)operon
B)operator
C)promoter
D)initiator

Question 37

When a DNA molecule is replicated,the daughter molecules contain one strand of parental DNA and one strand of newly synthesized DNA; this is called __________ replication.

A)hemiconservative
B)conservative
C)semiconservative
D)dispersive

Question 38

Which of the following nitrogenous bases is usually found in RNA but not in DNA?

A)adenine
B)thymine
C)uracil
D)guanine

Question 39

The coding sequence in the DNA of __________ is normally continuous; that is,it is not interrupted by noncoding sequences.

A)prokaryotes
B)plants
C)mammals
D)most insects

Question 40

Prokaryotic DNA replication occurs at a rate of

A)750-1,000 base pairs per second.
B)750-1,000 base pairs per minute.
C)50-100 base pairs per second.
D)50-100 base pairs per minute.

Question 41

The genetic code is translated in groups of __________ bases.

A)two
B)three
C)four
D)five

Question 42

Which of the following is not a termination codon?

A)AUG
B)UAA
C)UAG
D)UGA

Question 43

________ molecules deliver amino acids to ribosomes during translation.

A)Messenger RNA (mRNA)
B)Transfer RNA (tRNA)
C)Ribosomal RNA (rRNA)
D)Heterogeneous nuclear RNA (hnRNA)

Question 44

When RNA polymerase catalyzes the addition of a nucleotide to a growing mRNA chain,a byproduct of this reaction is

A)phosphate.
B)pyrophosphate.
C)orthophosphate.
D)water.

Question 45

Ribosomes consist of __________ separate subunits that come together as part of the initiation process and dissociate immediately after termination.

A)two
B)three
C)four
D)five

Question 46

In order to add a single amino acid to a growing polypeptide chain,a grand total of __________ molecules or ATP or GTP are utilized.

A)two
B)three
C)four
D)six

Question 47

In __________ ribosomes can attach to the mRNA and begin translation even though transcription has not been completed.

A)prokaryotes
B)eukaryotes
C)fungi
D)protozoa and some plants

Question 48

The genetic code is said to be __________ because more than one codon will specify a particular amino acid.

A)ambiguous
B)degenerate
C)multiplicative
D)repetitious

Question 49

A complex consisting of a single mRNA molecule with several ribosomes is called a

A)polysome.
B)multisome.
C)maxisome.
D)none of the choices

Question 50

Which of the following is the initiator codon?

A)AUG
B)UAA
C)UAG
D)UGA

Question 51

The process by which the base sequence of an RNA molecule is used to direct the synthesis of a protein is called

A)replication.
B)transcription.
C)reverse transcription.
D)translation.

Question 52

The stop codons are translated codons; that is,they specify amino acids to be inserted into the last position of a growing polypeptide chain.

Question 53

The process by which the base sequence of all or a portion of a DNA molecule is used to direct the synthesis of an RNA molecule is called

A)replication.
B)transcription.
C)reverse transcription.
D)translation.

Question 54

The portion of the tRNA molecule that binds to the codon on the mRNA is called the

A)c-codon.
B)anticodon.
C)complementary codon.
D)paracodon.

Question 55

What is the minimum number of aminoacyl-tRNA synthetase enzymes needed to attach amino acids to all the various tRNA molecules?

A)20.
B)61.
C)64.
D)as many as there are different tRNAs.

Question 56

The Pribnow box of

A)is centered approximately 35 bp upstream of the start site of transcription.
B)is centered between 7 and 13 bp upstream of the start codon.
C)is centered approximately 10 bp upstream of the start site of transcription.
D)is located at the site of addition of poly (A)in eukaryotic mRNAs.
E)coli

Question 57

The noncoding sequences located between the start codon and the stop codon in interrupted genes are called introns.

Question 58

The __________ reaction sequentially links adjacent amino acids into the growing polypeptide chain.

A)dipeptidation
B)transpeptidation
C)peptidation
D)propeptidation

Question 59

How many different termination codons are used in translation?

A)one
B)two
C)three
D)four

Question 60

Key sequences exist within promoters,which vary somewhat among various promoters but are sufficiently constant that they can be represented by a sequence of bases most often found at each position.These representations are called __________ sequences.

A)convergence
B)idealized
C)consensus
D)common

Question 61

Some microbial proteins are spliced after translation in a reaction that results in removal of one or more internal intervening sequences called inteins.

Question 62

The energy needed for protein synthesis is provided by the hydrolysis of

A)ATP.
B)GTP.
C)UTP.
D)ATP and GTP.
E)ATP and UTP.

Question 63

All prokaryotes initiate the synthesis of proteins with formylmethionine.