Deck 12: Gene Expression and Regulation

Question 1

Both DNA and RNA:

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

Answer 1

D

Question 2

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

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

Answer 2

E

Question 3

How many bases are in a codon?

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

Answer 3

A

Question 4

How can RNA be distinguished from DNA?

A)RNA has one polynucleotide strand per molecule.
B)RNA lacks the base uracil.
C)RNA might or might not possess the sugar deoxyribose.
D)RNA is never found in the nucleus.

Question 5

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

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

Question 6

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

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

Question 7

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

A)DNA
B)mRNA
C)tRNA
D)proteins
E)lipids

Question 8

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

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

Question 9

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

Question 10

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

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

Question 11

The genetic code is:

A)different in different organisms.
B)read in sets of three bases called codons.
C)used during the translation of DNA to mRNA.

Question 12

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

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

Question 13

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

A)adenine
B)uracil
C)thymine
D)phosphate groups
E)deoxyribose

Question 14

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

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

Question 15

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

A)RNA.
B)protein.
C)carbohydrate.
D)lipid.
E)single-stranded DNA.

Question 16

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

A)DNA
B)mRNA
C)tRNA
D)proteins
E)lipids

Question 17

The nitrogenous base uracil pairs with:

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

Question 18

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

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

Question 19

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

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

Question 20

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

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

Question 21

Which of the following has two polynucleotide strands?

A)ribosomal RNA
B)DNA
C)messenger RNA
D)transfer RNA
E)RNA polymerase

Question 22

All of the following are directly involved in translation EXCEPT:

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

Question 23

Transcription is the process of:

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

Question 24

Which of the following occurs in the nucleus?

A)transcription only
B)assembly of amino acids into protein only
C)replication of genetic material only
D)both transcription and replication of genetic material
E)translation only

Question 25

Ribosomes are a collection of:

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

Question 26

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)2
B)4
C)6
D)12

Question 27

Which of the following contains deoxyribose?

A)ribosomal RNA
B)DNA
C)messenger RNA
D)transfer RNA
E)RNA polymerase

Question 28

For a eukaryotic chromosome, which of the following is true?

A)RNA chains of different genes can be transcribed from either DNA strand, but the growing RNA strand always starts at the 5' end and moves toward the 3' end.
B)RNA chains of different genes can be transcribed from either DNA strand, but the growing RNA strand always starts at the 3' end and moves toward the 5' end.
C)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.
D)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.

Question 29

What is an anticodon?

A)four consecutive bases in tRNA
B)three consecutive bases in tRNA
C)the beginning of a DNA molecule
D)three consecutive bases in mRNA
E)three consecutive amino acids in a protein

Question 30

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

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

Question 31

What does mRNA carry away from the nucleus?

A)enzymes
B)ribosomes
C)information
D)amino acids
E)tRNA

Question 32

What is the site of protein synthesis?

A)smooth endoplasmic reticulum
B)nucleus
C)nucleolus
D)ribosome
E)eukaryotic chromosome

Question 33

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 34

The function of the promoter is to signal the RNA polymerase:

A)where to start transcribing the DNA.
B)which strand of the DNA to read.
C)where to start translating the DNA.

Question 35

What is the anticodon for AUC?

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

Question 36

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

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

Question 37

In eukaryotes, a promoter that signals the beginning of the gene is made from:

A)the bases TATAAA (most commonly)and response elements.
B)rRNA and tRNA.
C)the four different types of nucleotides and transcription factor binding sites.
D)transcription factor binding sites only.
E)both DNA and RNA.

Question 38

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

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

Question 39

Transfer RNA is:

A)a nucleic acid that, by itself, codes for the primary structure of a protein.
B)made directly from DNA during transcription.
C)permanently incorporated into the structure of ribosomes.
D)larger if the protein to be made has a longer amino acid sequence.

Question 40

A transcription start signal is called a(n):

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

Question 41

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)the deletion of three bases near the start of the coding sequence
E)a base insertion near the end of the coding sequence

Question 42

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

Question 43

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

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

Question 44

What molecule directly allows translation of the four-letter "nucleic acid language" (A, T, G, and C nucleotides)into the 20 "amino acid language" of proteins?

A)transfer RNA
B)ribosomal RNA
C)messenger RNA
D)DNA

Question 45

A tRNA molecule brings ________ to the ribosome during protein synthesis.

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

Question 46

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)AUG.
B)UAC.
C)UCA.
D)AGU.

Question 47

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

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

Question 48

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

A)insertion
B)deletion
C)substitution
D)neutral

Question 49

A random change in a DNA nucleotide base sequence:

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

Question 50

A gene mutation is defined as change in the:

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

Question 51

Which of the following elongates RNA molecules in the nucleus?

A)ribosomal RNA
B)DNA
C)messenger RNA
D)transfer RNA
E)RNA polymerase

Question 52

Which of the following has anticodons?

A)ribosomal RNA
B)DNA
C)messenger RNA
D)transfer RNA
E)RNA polymerase

Question 53

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

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

Question 54

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

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

Question 55

Which of the following attaches to specific amino acids?

A)ribosomal RNA
B)DNA
C)messenger RNA
D)transfer RNA
E)RNA polymerase

Question 56

Which of the following is made up of amino acids?

A)ribosomal RNA
B)DNA
C)messenger RNA
D)transfer RNA
E)RNA polymerase

Question 57

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

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

Question 58

Which of the following "reads" codons?

A)RNA polymerase
B)DNA
C)messenger RNA
D)transfer RNA

Question 59

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

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

Question 60

Which of the following contains codons?

A)ribosomal RNA
B)DNA
C)messenger RNA
D)transfer RNA
E)RNA polymerase

Question 61

Each ribosome is specific for a particular type of protein. True or False?

Question 62

What is the reason calico cats are almost always female?

A)inactivation of the X chromosome
B)lack of a Y chromosome in females
C)activation of the calico gene by the female sex hormone estrogen
D)inactivation of the calico gene in males by the sex hormone testosterone
E)a mutation on the X chromosome

Question 63

The anticodon for AUC is ________.

Question 64

A codon of mRNA consists of three bases that code for an amino acid. True or False?

Question 65

Your tongue does not grow hair because:

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

Question 66

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

Question 67

A random change in the DNA nucleotide base sequence is called a ________.

Question 68

Steroid hormones have the ability to regulate transcription. True or False?

Question 69

The Barr body is the X chromosome in the cell that is expressed, while the other X chromosome is inactivated. True or False?

Question 70

tRNA is necessary for transcription to occur. True or False?

Question 71

In eukaryotic cells, ________ occurs in the nucleus, resulting in the production of mRNA, which then travels to the cytoplasm for protein synthesis via ________.

Question 72

The strand of the DNA molecule that is used to transcribe from is called the ________ strand.

Question 73

"Gene expression" is a term that relates to:

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

Question 74

Each gene is specific for a particular type of protein. True or False?

Question 75

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

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

Question 76

Which of the following is TRUE regarding gene expression?

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

Question 77

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

A)Different RNA polymerases transcribe it and produce different proteins.
B)Different types of ribosomes translate the resulting mRNA, producing different proteins.
C)Different introns can be removed to produce different proteins.
D)The exons within a mRNA can be spliced together in different ways.

Question 78

The site of protein synthesis in the cytoplasm is the ribosome. True or False?

Question 79

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

A)regulating the life span of a protein
B)modifying proteins after they are synthesized
C)varying the rate at which messenger RNAs are translated
D)varying the rate at which messenger RNAs are transcribed
E)deleting genes from cells in which they are not needed

Question 80

Messenger RNA is single-stranded. True or False?