Deck 13: Gene Expression and Regulation

Question 1

If a bacterial protein is made from 30 amino acids, how many nucleotides are needed to code for its production?

A) 120
B) 600
C) 30
D) 60
E) 90

Answer 1

E

Question 2

The genetic code is

A) read in sets of three bases called codons.
B) used during the translation of DNA to mRNA.
C) a set of two base sequences coding for each amino acid.
D) different in different organisms.

Answer 2

A

Question 3

Which of the following is found in RNA but NOT in DNA?

A) Adenine
B) Thymine
C) Uracil
D) Deoxyribose
E) Phosphate groups

Answer 3

C

Question 4

What is the total number of different possible combinations of bases in a codon?

A) 20
B) 64
C) 3
D) 4

Question 5

The "one- gene, one- enzyme" hypothesis concluded that

A) specific enzymes give rise to specific genes.
B) each allele codes for a single type of protein.
C) only certain genes function in cells.
D) DNA is transcribed into RNA, which is translated into protein.
E) enzymes regulate gene activity.

Question 6

Both DNA and RNA

A) cannot be present in a cell simultaneously.
B) contain phosphate groups.
C) contain the same four types of nitrogen- containing bases.
D) are single- stranded molecules.
E) have the same five- carbon sugars.

Question 7

The sequence of nitrogen- containing bases on one strand of DNA most directly determines the sequence of

A) sugars in a polysaccharide molecule.
B) amino acids in a protein molecule.
C) fatty acids in a fat molecule.
D) bases in a protein molecule.

Question 8

Which of the following molecules transfers information from the nucleus to the cytoplasm?

A) mRNA
B) tRNA
C) DNA
D) Proteins
E) Lipids

Question 9

If the sequence of bases in a section of DNA is TAGGCTAA, what is the corresponding sequence of bases in mRNA?

A) ATCCGATT
B) AUCCGAUU
C) AATCGGAT
D) TAGGCTAA
E) CGAAUCGG

Question 10

The nitrogenous base uracil pairs with

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

Question 11

The sequence of nitrogen- containing bases on one strand of DNA could determine all of the following EXCEPT the sequence of

A) amino acids in a protein molecule.
B) ribose and phosphate molecules in tRNA.
C) nitrogen- containing bases in mRNA.
D) nitrogen- containing bases in the other DNA strand.

Question 12

How many bases are in a codon?

A) 4
B) 3
C) 20
D) 64

Question 13

The genetic material of some viruses, such as HIV, is not DNA but is instead

A) carbohydrate.
B) RNA.
C) lipid.
D) protein.

Question 14

How can RNA be distinguished from DNA?

A) RNA is never found in the nucleus.
B) RNA does not contain a sugar.
C) RNA is single- stranded.
D) RNA lacks the base uracil.

Question 15

Which of the following molecules function to transfer genetic information from one generation to the next?

A) mRNA
B) DNA
C) tRNA
D) Protein molecules
E) Lipid molecules

Question 16

How many consecutive mRNA bases are needed to specify an amino acid?

A) 4
B) 20
C) 3
D) 64

Question 17

If a tRNA molecule that is specialized for the transfer of the amino acid valine has the anticodon CAG, it will couple with the codon

A) GTC.
B) TUG.
C) CAG.
D) GAC.
E) GUC.

Question 18

Which of the following has the fewest nucleotides in its strand?

A) Protein, having 40 amino acids
B) mRNA, having 75 nucleotides
C) Protein, with 2 polypeptides, each having 35 amino acids
D) mRNA, having 50 codons
E) mRNA, having 100 bases

Question 19

Which of the following is noted when comparing DNA and RNA?

A) No sugar is present in either molecule.
B) Only DNA has a backbone made up of sugars and phosphates.
C) Hydrogen bonding is important only in DNA.
D) Adenine pairs with different bases in DNA and RNA.
E) Thymine pairs with different bases in DNA and RNA.

Question 20

The process of copying genetic information from DNA to RNA is called

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

Question 21

Ribosomes are a collection of

A) proteins and mRNAs that function in translation.
B) small proteins that function in translation.
C) proteins and tRNAs that function in transcription.
D) mRNAs and tRNAs that function in translation.
E) proteins and small RNAs that function in translation.

Question 22

What is an anticodon?

A) Three consecutive amino acids in a protein
B) Three consecutive bases in mRNA
C) Three consecutive bases in tRNA
D) The beginning of a DNA molecule
E) Four consecutive bases in tRNA

Question 23

Transcription is the process of

A) synthesizing an RNA molecule using a DNA template.
B) synthesizing a protein using information from mRNA.
C) synthesizing a DNA molecule from an RNA template.
D) replicating a single- stranded DNA molecule.
E) assembling an RNA molecule without a template.

Question 24

Which of the following contains four types of nucleotides but no uracil?

A) Ribosomal RNA
B) DNA
C) Messenger RNA
D) Transfer RNA
E) RNA polymerase

Question 25

Which of the following occurs in the nucleus?

A) Transcription only
B) Replication of genetic material only
C) Translation only
D) Both translation and replication of genetic material
E) Both transcription and replication of genetic material

Question 26

Which statement correctly describes transcription?

A) RNA chains of all genes are synthesized from the same DNA strand, with the growing RNA strand always starting at the 3' end and moving toward the 5' end.
B) RNA chains of all genes are synthesized from the same DNA strand, with the growing RNA strand always starting at the 5' end and moving toward the 3' end.
C) RNA chains of different genes can be transcribed from either DNA strand, with RNA polymerase traveling from the 5' end and moving toward the 3' end.
D) RNA chains of different genes can be transcribed from either DNA strand, with RNA polymerase traveling from the 3' end and moving toward the 5' end.

Question 27

What does mRNA carry away from the nucleus?

A) Ribosomes
B) Information
C) tRNA
D) Amino acids
E) Enzymes

Question 28

Suppose one strand of a "mini- gene" has the base sequence TACCCGGATTCA. The last codon in the mRNA sequence will be

A) AGU.
B) UGA.
C) TCA.
D) AGT.

Question 29

What is the site of protein synthesis in the cell?

A) Ribosome
B) Nucleus
C) Nucleolus
D) Smooth endoplasmic reticulum
E) Eukaryotic chromosome

Question 30

Suppose one strand of a "mini- gene" has the base sequence TACCCGGATTCA. If we assume no introns are involved, how many amino acids does the polypeptide encoded by this gene have?

A) 12
B) 4
C) 2
D) 6

Question 31

The function of the promoter is to signal the RNA polymerase

A) where to start translating the DNA.
B) which strand of the DNA to read.
C) where to start transcribing the DNA.
D) where to add the first amino acid to the protein.

Question 32

The process of converting the "message" of mRNA into a sequence of amino acids is called

A) replication.
B) activation.
C) translation.
D) repression.
E) transcription.

Question 33

Transfer RNA

A) is a subunit of ribosomes.
B) brings amino acids to the ribosome.
C) is a nucleic acid that carries the code for the primary structure of a protein.
D) transfers proteins into the nucleus.

Question 34

The type of RNA that binds to a specific amino acid is

A) transfer RNA.
B) ribosomal RNA.
C) messenger RNA.
D) nuclear RNA.

Question 35

A transcription start signal is called a(n)

A) initiation codon.
B) nonsense codon.
C) origin.
D) promoter.
E) start site.

Question 36

Which of the following has two polynucleotide strands?

A) Ribosomal RNA
B) DNA
C) Messenger RNA
D) Transfer RNA
E) RNA polymerase

Question 37

Which of the following contains deoxyribose?

A) Ribosomal RNA
B) DNA
C) Messenger RNA
D) Transfer RNA
E) RNA polymerase

Question 38

All of the following are directly involved in translation EXCEPT

A) mRNA.
B) amino acids.
C) ribosomes.
D) tRNA.
E) DNA.

Question 39

What is the anticodon for AUC?

A) AUC
B) TAG
C) CUA
D) UAG
E) GAU

Question 40

In eukaryotes, a promoter that signals the beginning of the gene and binds with the promoter typically consists of

A) both DNA and RNA.
B) the base sequence AUG and transcription factor binding sites.
C) the bases TATAAA and response elements.
D) rRNA and tRNA.

Question 41

Which of the following attaches to specific amino acids?

A) DNA
B) Messenger RNA
C) RNA polymerase
D) Ribosomal RNA
E) Transfer RNA

Question 42

Which point mutation would be most likely to have a catastrophic effect?

A) A base substitution
B) A base deletion near the start of the coding sequence
C) A base deletion near the end of the coding sequence
D) A base insertion near the end of the coding sequence
E) The deletion of three bases near the start of the coding sequence

Question 43

In a wild- type strain of fruit flies, the length of a gene from the start to the stop codon is 2,000 DNA bases. Suppose an experiment indicated that the mRNA molecule transcribed from this gene is much shorter (only 1,200 bases). What is the most likely explanation for this?

A) The first 800 bases of DNA are always cut out as it is transcribed into mRNA.
B) The mRNA was prematurely degraded.
C) There are introns in the DNA that were cut out of the mRNA.
D) A mutation caused the formation of an extra stop codon in the gene.

Question 44

What molecule is responsible for translation of the four- letter "nucleic acid language" (A, T, G, and C nucleotides) into the 20 "amino acid language" of proteins by bringing in amino acids to the ribosome?

A) Messenger RNA
B) Transfer RNA
C) DNA
D) Ribosomal RNA

Question 45

A gene can be mutated with no resulting functional change in the protein that is produced from that gene if

A) a codon has changed, but it codes for the same amino acid as the original codon.
B) RNA polymerase can edit the mutation from the mRNA produced during translation.
C) the mutation alters the active site of an enzyme.
D) an entire codon has been removed.

Question 46

A gene mutation is defined as change in the

A) nucleotide sequence of DNA.
B) activation of a gene.
C) nucleotide sequence of RNA.
D) structure of ribosomes.

Question 47

For a mutation to affect the evolution of an animal species, it must occur within

A) prokaryotic cells.
B) diploid cells.
C) gametes.
D) somatic cells.

Question 48

Which of the following binds to codons?

A) Transfer RNA
B) Messenger RNA
C) RNA polymerase
D) DNA

Question 49

A tRNA that carries a specific amino acid enters the protein- synthesizing machinery at the ribosomes and pairs with the appropriate

A) anticodon.
B) amino acid.
C) charge.
D) codon.

Question 50

A tRNA molecule brings to the ribosome during protein synthesis.

A) an amino acid
B) RNA polymerase
C) a polypeptide
D) mRNA

Question 51

Which of the following contains codons?

A) Transfer RNA
B) Messenger RNA
C) Ribosomal RNA
D) DNA
E) RNA polymerase

Question 52

A mutation that results in a change in the codon- reading pattern could result from

A) a base deletion only.
B) either an insertion or a deletion of a base.
C) a base substitution only.
D) a base insertion only.

Question 53

What kind of mutation occurs when one base is changed to another at a single location in the DNA?

A) Neutral
B) Substitution
C) Insertion
D) Deletion

Question 54

Which of the following synthesizes RNA molecules in the nucleus?

A) Ribosomal RNA
B) RNA polymerase
C) Transfer RNA
D) Messenger RNA
E) DNA

Question 55

Which of the following is a protein made up of amino acids?

A) Transfer RNA
B) Messenger RNA
C) DNA
D) Uracil
E) RNA polymerase

Question 56

The manufacture of proteins from RNA and amino acids is referred to as

A) transcription.
B) replication.
C) activation.
D) translation.
E) transformation.

Question 57

A random change in a DNA nucleotide base sequence

A) is never beneficial to the organism.
B) is never apparent in the organism.
C) cannot have an influence on genetic variation.
D) always kills the cell.
E) represents a mutation.

Question 58

Suppose the template DNA strand of a "mini- gene" has the base sequence TACCCGGATTCA. The anticodon of the tRNA that carries the first amino acid to the ribosome will be

A) AGU.
B) AUG.
C) UAC.
D) UAG.
E) UCA.

Question 59

Which of the following has anticodons?

A) Messenger RNA
B) Ribosomal RNA
C) Transfer RNA
D) RNA polymerase
E) DNA

Question 60

A sequence of three RNA bases can function as a(n)

A) anticodon only.
B) codon or anticodon.
C) gene only.
D) codon only.

Question 61

Each ribosome is specific for a particular type of protein.

Question 62

A codon of mRNA consists of three bases that code for an amino acid.

Question 63

Which of the following is TRUE regarding gene expression?

A) Gene expression is not influenced by the environment.
B) Different tissues within an organism express different genes.
C) Gene expression remains constant throughout an organism's life span.
D) Different individuals of the same species express all of the same genes.

Question 64

In eukaryotic cells, occurs in the nucleus, resulting in the production of mRNA, which then travels to the ribosome for into an amino acid chain.

Question 65

How can a single gene code for more than one protein?

A) Different amino acid chains can be coded by the same mRNA.
B) Different RNA polymerases transcribe it and produce different proteins.
C) Different types of ribosomes translate the resulting mRNA, producing different proteins.
D) The exons within an mRNA can be spliced together in different ways.

Question 66

The fact that calico cats are only female supports the theory of

A) testosterone inactivation of Y- chromosome genes.
B) two X chromosomes being required for coat color in cats.
C) mutations in all genes on one X chromosome.
D) X- chromosome inactivation and Barr bodies in females.

Question 67

What is an advantage to an organism producing microRNA?

A) microRNA can protect against viral infections.
B) microRNA causes mutations in unused genes.
C) microRNA can protect against heart disease and cancer.
D) microRNA allows for the inactivation of Barr bodies.

Question 68

The strand of the DNA molecule that is transcribed is called the _ strand.

Question 69

Steroid hormones have the ability to regulate transcription.

Question 70

Messenger RNA is single- stranded.

Question 71

The Barr body is the X chromosome in the cell that is expressed, whereas the other X chromosome is inactivated.

Question 72

tRNA is necessary for transcription to occur.

Question 73

In general, each gene codes for a specific protein.

Question 74

A "mini- gene" has the base sequence TACCCGTGCACG. If the T at the beginning of the sequence is deleted, what will be the consequence?

A) The first nucleotide is always replaced anyway, so there will be no change.
B) RNA polymerase will correct the deletion, and a normal protein will be produced.
C) All of the codons after that point will be changed.
D) Only the amino acid coded for in that codon will be changed.
E) RNA polymerase will skip that codon, but all the others will be read normally.

Question 75

The site of protein synthesis in the cytoplasm is the ribosome.

Question 76

Which of the following is NOT a theory of epigenetics explaining how cells can change gene function without changing the DNA base sequence?

A) Altering transcription and translation with noncoding RNA
B) Mutations causing new beneficial alleles
C) Modification of chromosomal proteins
D) Modification of DNA

Question 77

Which of the following is NOT a means of regulating gene expression?

A) Varying the rate at which messenger RNAs are transcribed
B) Modifying proteins after they are synthesized
C) Regulating how long a protein lasts in a cell
D) Varying the rate at which messenger RNAs are translated
E) Deleting genes from cells in which they are not needed

Question 78

Your tongue does NOT grow hair because

A) the genes for hair proteins have been deleted from the cells of your tongue.
B) different genes are expressed in different tissues.
C) saliva prevents hair from growing.
D) skin cells have extra DNA that codes for hair proteins.

Question 79

A "mini- gene" has the base sequence TACCCGTGCACG. Which of the following sequences represents a single base substitution?

A) TACCCGTGCACG
B) TACCGTGCTACG
C) TACCCGAGCACG
D) TACCCGTGTCACG
E) TACCCGGCACG

Question 80

Gene expression is a term that relates to

A) how genes are passed from parent to offspring.
B) the karyotype of a chromosome set.
C) the unique set of genes in an individual.
D) the flow of genetic information from DNA to proteins.
E) DNA replication.