Question 1

A codon is _______ nucleotides long, and there are _______ different possible codons in total.

Accepted Answer

A)  2; 16 
B)  2; 64 
C)  3; 16 
D)  3; 64 
E)  4; 64 
A)  2; 16 
B)  2; 64 
C)  3; 16 
D)  3; 64 
E)  4; 64

Question 2

Translation of an mRNA transcript generates numerous polypeptide chains.The accumulation of these polypeptide chains is faster than can be accounted for when considering the rate of ribosomal-mediated translation of mRNA transcripts.What accounts for this discrepancy?

Accepted Answer

A)  The process cannot be accurately measured. 
B)  There are multiple mRNA transcripts per ribosome. 
C)  mRNA transcripts are translated by polysomes. 
D)  Each tRNA binds multiple ribosomes at the same time. 
E)  Some tRNAs bind inosine. 
A)  The process cannot be accurately measured. 
B)  There are multiple mRNA transcripts per ribosome. 
C)  mRNA transcripts are translated by polysomes. 
D)  Each tRNA binds multiple ribosomes at the same time. 
E)  Some tRNAs bind inosine.

Question 3

Which statement about RNA is false?

Accepted Answer

A)  Transfer RNA functions in translation. 
B)  Ribosomal RNA functions in translation. 
C)  RNAs are produced by transcription. 
D)  Messenger RNAs are produced on ribosomes. 
E)  DNA codes for mRNA, tRNA, and rRNA. 
A)  Transfer RNA functions in translation. 
B)  Ribosomal RNA functions in translation. 
C)  RNAs are produced by transcription. 
D)  Messenger RNAs are produced on ribosomes. 
E)  DNA codes for mRNA, tRNA, and rRNA.

Question 4

The mRNA start codon is AUG and codes for the amino acid _______.

Accepted Answer

The answer of The mRNA start codon is AUG and...

Question 5

The Beadle and Tatum experiment used X rays

Accepted Answer

A)  to identify mutant genes. 
B)  as an energy source. 
C)  to generate mutations. 
D)  to accelerate metabolism. 
E)  as a substitute for enzymes. 
A)  to identify mutant genes. 
B)  as an energy source. 
C)  to generate mutations. 
D)  to accelerate metabolism. 
E)  as a substitute for enzymes.

Question 6

Inosine, which is sometimes found at the _______ end of an anticodon, can pair with any of the bases normally seen in RNA except _______.

Accepted Answer

A)  5F1F1F1S1F1F1F10; A 
B)  5F1F1F1S1F1F1F10; C 
C)  5F1F1F1S1F1F1F10; G 
D)  3F1F1F1S1F1F1F10; C 
E)  3F1F1F1S1F1F1F10; G 
A)  5F1F1F1S1F1F1F10; A 
B)  5F1F1F1S1F1F1F10; C 
C)  5F1F1F1S1F1F1F10; G 
D)  3F1F1F1S1F1F1F10; C 
E)  3F1F1F1S1F1F1F10; G

Question 7

Geneticists would expect alkaptonuria to be _______ common when there is mating between relatives, because the condition is inherited as a _______ phenotype.

Accepted Answer

A)  more; dominant 
B)  more; recessive 
C)  more; codominant 
D)  less; dominant 
E)  less; recessive 
A)  more; dominant 
B)  more; recessive 
C)  more; codominant 
D)  less; dominant 
E)  less; recessive

Question 8

Consider the typical multicellular eukaryote.In comparison with the DNA made in DNA replication, transcribed mRNAs are made in _______ copies, are _______ error prone, and last _______.

Accepted Answer

A)  more; more; longer 
B)  more; more; a shorter time 
C)  more; less; a shorter time 
D)  fewer; more; longer 
E)  fewer; less; longer 
A)  more; more; longer 
B)  more; more; a shorter time 
C)  more; less; a shorter time 
D)  fewer; more; longer 
E)  fewer; less; longer

Question 9

Suppose you take the glycine tRNA and modify it so that the glycine is changed to valine.Based on the results of the Benzer experiments, _______, because the protein synthesis machinery recognizes the _______.

Accepted Answer

A)  nothing should change in proteins; amino acid attached to the tRNA 
B)  nothing should change in proteins; tRNA anticodon 
C)  proteins would have valines where glycines normally are; amino acid attached to the tRNA 
D)  proteins would have valines where glycines normally are; tRNA anticodon 
E)  proteins would have glycines where valines normally are; amino acid attached to the tRNA 
A)  nothing should change in proteins; amino acid attached to the tRNA 
B)  nothing should change in proteins; tRNA anticodon 
C)  proteins would have valines where glycines normally are; amino acid attached to the tRNA 
D)  proteins would have valines where glycines normally are; tRNA anticodon 
E)  proteins would have glycines where valines normally are; amino acid attached to the tRNA

Question 10

Refer to the figure.   What is the location of the anticodon site of this tRNA molecule?

Accepted Answer

The answer of Refer to the figure.   What...

Question 11

At which sites on the ribosome is the tRNA never charged?

Accepted Answer

A)  At the A site 
B)  At the P site 
C)  At the E site 
D)  At both the A and P sites 
E)  None of the above; the tRNA is always charged when it interacts with the ribosome. 
A)  At the A site 
B)  At the P site 
C)  At the E site 
D)  At both the A and P sites 
E)  None of the above; the tRNA is always charged when it interacts with the ribosome.

Question 12

The current genetic code evolved

Accepted Answer

A)  before the common ancestor of all extant life. 
B)  after the common ancestor of all extant life but before eukaryotes split from the other domains of life. 
C)  after eukaryotes split from other domains of life but before the split of multicellular animals and multicellular plants. 
D)  after the split of multicellular animals and multicellular plants but before the common ancestor of chordates. 
E)  after the common ancestor of chordates. 
A)  before the common ancestor of all extant life. 
B)  after the common ancestor of all extant life but before eukaryotes split from the other domains of life. 
C)  after eukaryotes split from other domains of life but before the split of multicellular animals and multicellular plants. 
D)  after the split of multicellular animals and multicellular plants but before the common ancestor of chordates. 
E)  after the common ancestor of chordates.

Question 13

Which statement about glycoproteins is true?

Accepted Answer

A)  They are commonly located in the cytoplasm of eukaryotic cells. 
B)  They are formed after translation of the protein in the cytoplasm. 
C)  They may be incorporated into plasma membranes or vesicles. 
D)  The sugars are added to the proteins solely in the RER. 
E)  Sugar addition to proteins inhibits their signaling function. 
A)  They are commonly located in the cytoplasm of eukaryotic cells. 
B)  They are formed after translation of the protein in the cytoplasm. 
C)  They may be incorporated into plasma membranes or vesicles. 
D)  The sugars are added to the proteins solely in the RER. 
E)  Sugar addition to proteins inhibits their signaling function.

Question 14

In the process of transcription,

Accepted Answer

A)  a DNA molecule is synthesized from an RNA template. 
B)  ribonucleoside triphosphates are assembled into an RNA molecule in the absence of a template. 
C)  an RNA molecule is synthesized from a DNA template. 
D)  a protein is synthesized with the use of information from a messenger RNA. 
E)  a single-stranded DNA molecule is replicated. 
A)  a DNA molecule is synthesized from an RNA template. 
B)  ribonucleoside triphosphates are assembled into an RNA molecule in the absence of a template. 
C)  an RNA molecule is synthesized from a DNA template. 
D)  a protein is synthesized with the use of information from a messenger RNA. 
E)  a single-stranded DNA molecule is replicated.

Question 15

Comparison of the same gene and its product in two different animal species revealed that the amino acids are 98 percent identical but the nucleotides are only 86 percent identical.What accounts for the much higher amino acid identity than nucleotide identity?

Accepted Answer

A)  The genetic code is redundant. 
B)  The genetic code differs between species. 
C)  The researchers sequenced different template strands. 
D)  The genetic code is nonredundant. 
E)  The genetic code is ambiguous. 
A)  The genetic code is redundant. 
B)  The genetic code differs between species. 
C)  The researchers sequenced different template strands. 
D)  The genetic code is nonredundant. 
E)  The genetic code is ambiguous.

Question 16

The wobble phenomenon occurs at _______end of the anticodon and helps explain why the _______ end of the codon shows the most redundancy.

Accepted Answer

A)  the 5ʹ; 3ʹ 
B)  the 3ʹ; 5ʹ 
C)  the 3ʹ; 3ʹ 
D)  the 5ʹ; 5ʹ 
E)  either; 5ʹ 
A)  the 5ʹ; 3ʹ 
B)  the 3ʹ; 5ʹ 
C)  the 3ʹ; 3ʹ 
D)  the 5ʹ; 5ʹ 
E)  either; 5ʹ

Question 17

A mutation in a protein kinase can lead to improper _______ of proteins.

Accepted Answer

A)  transport 
B)  kinetics 
C)  glycosylation 
D)  splicing 
E)  phosphorylation 
A)  transport 
B)  kinetics 
C)  glycosylation 
D)  splicing 
E)  phosphorylation

Question 18

The study of Neurospora mutants grown on various supplemented media enabled researchers to identify single genes involved in the arginine synthesis pathway.Why was Neurospora a better model organism than a human cell line for this study?

Accepted Answer

A)  Neurospora DNA is more sensitive to X rays than human DNA. 
B)  The arginine synthesis pathway is less complex in Neurospora. 
C)  Arginine is an essential amino acid in human cells. 
D)  All human alleles are expressed phenotypically. 
E)  All Neurospora alleles are expressed phenotypically. 
A)  Neurospora DNA is more sensitive to X rays than human DNA. 
B)  The arginine synthesis pathway is less complex in Neurospora. 
C)  Arginine is an essential amino acid in human cells. 
D)  All human alleles are expressed phenotypically. 
E)  All Neurospora alleles are expressed phenotypically.

Question 19

A charged tRNA travels across a ribosome from the _______ site, to the _______ site, and then to the _______ site.

Accepted Answer

A)  A; E; P 
B)  A; P; E 
C)  E; P; A 
D)  P; E; A 
E)  P; A; E 
A)  A; E; P 
B)  A; P; E 
C)  E; P; A 
D)  P; E; A 
E)  P; A; E

Question 20

The template in transcription is a(n)

Accepted Answer

A)  primer. 
B)  enzyme. 
C)  strand of DNA. 
D)  strand of RNA. 
E)  ribonucleoside triphosphate. 
A)  primer. 
B)  enzyme. 
C)  strand of DNA. 
D)  strand of RNA. 
E)  ribonucleoside triphosphate.

Exam 14: From Dna to Protein: Gene Expression

A codon is _______ nucleotides long, and there are _______ different possible codons in total.

Translation of an mRNA transcript generates numerous polypeptide chains.The accumulation of these polypeptide chains is faster than can be accounted for when considering the rate of ribosomal-mediated translation of mRNA transcripts.What accounts for this discrepancy?

Which statement about RNA is false?

The mRNA start codon is AUG and codes for the amino acid _______.

The Beadle and Tatum experiment used X rays

Inosine, which is sometimes found at the _______ end of an anticodon, can pair with any of the bases normally seen in RNA except _______.

Geneticists would expect alkaptonuria to be _______ common when there is mating between relatives, because the condition is inherited as a _______ phenotype.

Consider the typical multicellular eukaryote.In comparison with the DNA made in DNA replication, transcribed mRNAs are made in _______ copies, are _______ error prone, and last _______.

Suppose you take the glycine tRNA and modify it so that the glycine is changed to valine.Based on the results of the Benzer experiments, _______, because the protein synthesis machinery recognizes the _______.

Refer to the figure. What is the location of the anticodon site of this tRNA molecule?

At which sites on the ribosome is the tRNA never charged?

The current genetic code evolved

Which statement about glycoproteins is true?

In the process of transcription,

Comparison of the same gene and its product in two different animal species revealed that the amino acids are 98 percent identical but the nucleotides are only 86 percent identical.What accounts for the much higher amino acid identity than nucleotide identity?

The wobble phenomenon occurs at _______end of the anticodon and helps explain why the _______ end of the codon shows the most redundancy.

A mutation in a protein kinase can lead to improper _______ of proteins.

The study of Neurospora mutants grown on various supplemented media enabled researchers to identify single genes involved in the arginine synthesis pathway.Why was Neurospora a better model organism than a human cell line for this study?

A charged tRNA travels across a ribosome from the _______ site, to the _______ site, and then to the _______ site.

The template in transcription is a(n)

Studying Life

Small Molecules and the Chemistry of Life

Proteins, Carbohydrates, and Lipids

Nucleic Acids and the Origin of Life

Cells: the Working Units of Life

Cell Membranes

Cell Communication and Multicellularity

Energy, Enzymes, and Metabolism

Pathways That Harvest Chemical Energy

Photosynthesis: Energy From Sunlight

The Cell Cycle and Cell Division

Inheritance, Genes, and Chromosomes

Dna and Its Role in Heredity

Gene Mutation and Molecular Medicine

Regulation of Gene Expression

Genomes

Recombinant Dna and Biotechnology

Mechanisms of Evolution

Reconstructing and Using Phylogenies

Speciation

Evolution of Genes and Genomes

The History of Life on Earth

Bacteria, Archaea, and Viruses

The Origin and Diversification of Eukaryotes

Plants Without Seeds: From Water to Land

The Evolution of Seed Plants

The Evolution and Diversity of Fungi

Animal Origins and the Evolution of Body Plans

Protostome Animals

Deuterostome Animals

The Plant Body

Transport in Plants

Plant Nutrition

Regulation of Plant Growth

Reproduction in Flowering Plants

Plant Responses to Environmental Challenges

Physiology, Homeostasis, and Temperature Regulation

Animal Hormones

Immunology: Animal Defense Systems

Animal Reproduction

Animal Development

Neurons, Glia, and Nervous Systems

Sensory Systems

The Mammalian Nervous System: Structure and Higher Functions

Musculoskeletal Systems

Gas Exchange

Circulatory Systems

Nutrition, Digestion, and Absorption

Salt and Water Balance and Nitrogen Excretion

Animal Behavior

The Physical Environment and Biogeography of Life

Populations

Species Interactions

Communities

Ecosystems

A Changing Biosphere

Filters

A codon is _ nucleotides long, and there are _ different possible codons in total.

Inosine, which is sometimes found at the _ end of an anticodon, can pair with any of the bases normally seen in RNA except _.

Geneticists would expect alkaptonuria to be _ common when there is mating between relatives, because the condition is inherited as a _ phenotype.

Consider the typical multicellular eukaryote.In comparison with the DNA made in DNA replication, transcribed mRNAs are made in ___ copies, are _ error prone, and last _____.

Suppose you take the glycine tRNA and modify it so that the glycine is changed to valine.Based on the results of the Benzer experiments, _, because the protein synthesis machinery recognizes the _.

The wobble phenomenon occurs at _end of the anticodon and helps explain why the _ end of the codon shows the most redundancy.

A charged tRNA travels across a ribosome from the ___ site, to the _ site, and then to the _____ site.