MOLECULAR BIOLOGY OF THE CELL, SIXTH EDITION
CHAPTER 1: CELLS AND GENOMES
© Garland Science 2015
1.1 Scientists discover more than ten thousand new species of living organisms every year. What is shared between all of these organisms?
A. They are made of cells, whose nuclei enclose their DNA.
B. They obtain their energy from sunlight.
C. They produce and use adenosine triphosphate (ATP).
D. Their genome contains at least 1000 genes.
E. All of the above.
2.2 All cells …
A. have membrane transport proteins.
B. synthesize proteins on the ribosome.
C. replicate their genome by DNA polymerization.
D. transcribe their genetic information by RNA polymerization.
E. All of the above.
7.3 Imagine a segment of DNA (within a gene) encoding a certain amount of information in its nucleotide sequence. When this segment is fully transcribed into mRNA and then translated into protein, in general, …
A. the protein sequence would carry more information compared to the DNA and mRNA sequences, because its alphabet has 20 letters.
B. the protein sequence would carry less information compared to the DNA and mRNA sequences, because several codons can correspond to one amino acid.
C. the amount of information in the mRNA sequence is lower, because the mRNA has been transcribed using only one of the DNA strands as the template.
D. the amount of information in the mRNA sequence is higher, because several mRNA molecules can be transcribed from one DNA molecule.
8.4 Which of the following processes that happens inside a cell DOES NOT normally require consumption of free energy by the cell?
A. Replication of the genetic material
B. Import of nutrients from the environment
C. Diffusion of small molecules within the cell
D. Regulation of gene expression
E. Synthesis of enzymes that catalyze cellular reactions
9.5 Which of the following would you NOT expect to find in a bacterial cell?
A. Swimming using flagella
B. Having a cell wall around the plasma membrane
C. ATP production in mitochondria
D. Protein production on the ribosome
E. Sexual exchange of DNA with other bacteria
10.6 To trace family relationships between distantly related organisms such as humans, algae, bacteria, and archaea, one should compare their genomes in regions …
A. that evolve rapidly.
B. that have a higher mutation rate.
C. that code for proteins.
D. where mutations are hardly tolerated.
E. where most mutations are selectively neutral.
10.7 Laboratory strains of the model organism Escherichia coli that are resistant to antibiotics are very often used in research laboratories as well as in the biotechnology industry. If cultures of such bacteria were allowed to contaminate the environment uncontrollably, it is possible that at some point, pathogenic bacteria such as Neisseria meningitidis (which causes meningitis and can cause death, especially in children) could acquire the same antibiotic-resistance gene, causing a meningitis outbreak that is difficult to treat. In this scenario, which of the following mechanisms is a more likely source of the antibiotic-resistance gene in N. meningitidis?
A. Random new gene generation
B. Intragenic mutation
C. Gene duplication
D. DNA segment shuffling
E. Horizontal gene transfer
10.8 A virus …
A. is a type of cell.
B. has genetic material made of proteins.
C. can only infect a single host species.
D. can act as a vector for gene transfer.
E. cannot persist in its host for more than one cell generation.
10.9 Which of the following does NOT typically involve horizontal gene transfer?
A. Sexual reproduction in humans
B. Bacteriophage infection of bacteria
C. The evolutionary history of the eukaryotic cell
D. The accidental duplication of a small region of a bacterial chromosome followed by cell division
E. Introduction of plasmids into bacteria in a laboratory
10.10 Gene duplication can give rise to homologous genes that are part of gene families. For example, there are six actin genes in the genome of most mammalian species. In humans, the ACTB gene, which encodes a cytoskeletal actin, is expressed ubiquitously, while ACTC1 is expressed mainly in cardiac cells. Although bacteria lack the eukaryotic cytoskeletal organization, the bacterial MreB gene bears recognizable sequence similarity to mammalian actin genes and codes for a protein that is similar to actin in structure and function. Which of the following statements is true about these genes?
CHAPTER 1: CELLS AND GENOMES
© Garland Science 2015
1.1 Scientists discover more than ten thousand new species of living organisms every year. What is shared between all of these organisms?
A. They are made of cells, whose nuclei enclose their DNA.
B. They obtain their energy from sunlight.
C. They produce and use adenosine triphosphate (ATP).
D. Their genome contains at least 1000 genes.
E. All of the above.
2.2 All cells …
A. have membrane transport proteins.
B. synthesize proteins on the ribosome.
C. replicate their genome by DNA polymerization.
D. transcribe their genetic information by RNA polymerization.
E. All of the above.
7.3 Imagine a segment of DNA (within a gene) encoding a certain amount of information in its nucleotide sequence. When this segment is fully transcribed into mRNA and then translated into protein, in general, …
A. the protein sequence would carry more information compared to the DNA and mRNA sequences, because its alphabet has 20 letters.
B. the protein sequence would carry less information compared to the DNA and mRNA sequences, because several codons can correspond to one amino acid.
C. the amount of information in the mRNA sequence is lower, because the mRNA has been transcribed using only one of the DNA strands as the template.
D. the amount of information in the mRNA sequence is higher, because several mRNA molecules can be transcribed from one DNA molecule.
8.4 Which of the following processes that happens inside a cell DOES NOT normally require consumption of free energy by the cell?
A. Replication of the genetic material
B. Import of nutrients from the environment
C. Diffusion of small molecules within the cell
D. Regulation of gene expression
E. Synthesis of enzymes that catalyze cellular reactions
9.5 Which of the following would you NOT expect to find in a bacterial cell?
A. Swimming using flagella
B. Having a cell wall around the plasma membrane
C. ATP production in mitochondria
D. Protein production on the ribosome
E. Sexual exchange of DNA with other bacteria
10.6 To trace family relationships between distantly related organisms such as humans, algae, bacteria, and archaea, one should compare their genomes in regions …
A. that evolve rapidly.
B. that have a higher mutation rate.
C. that code for proteins.
D. where mutations are hardly tolerated.
E. where most mutations are selectively neutral.
10.7 Laboratory strains of the model organism Escherichia coli that are resistant to antibiotics are very often used in research laboratories as well as in the biotechnology industry. If cultures of such bacteria were allowed to contaminate the environment uncontrollably, it is possible that at some point, pathogenic bacteria such as Neisseria meningitidis (which causes meningitis and can cause death, especially in children) could acquire the same antibiotic-resistance gene, causing a meningitis outbreak that is difficult to treat. In this scenario, which of the following mechanisms is a more likely source of the antibiotic-resistance gene in N. meningitidis?
A. Random new gene generation
B. Intragenic mutation
C. Gene duplication
D. DNA segment shuffling
E. Horizontal gene transfer
10.8 A virus …
A. is a type of cell.
B. has genetic material made of proteins.
C. can only infect a single host species.
D. can act as a vector for gene transfer.
E. cannot persist in its host for more than one cell generation.
10.9 Which of the following does NOT typically involve horizontal gene transfer?
A. Sexual reproduction in humans
B. Bacteriophage infection of bacteria
C. The evolutionary history of the eukaryotic cell
D. The accidental duplication of a small region of a bacterial chromosome followed by cell division
E. Introduction of plasmids into bacteria in a laboratory
10.10 Gene duplication can give rise to homologous genes that are part of gene families. For example, there are six actin genes in the genome of most mammalian species. In humans, the ACTB gene, which encodes a cytoskeletal actin, is expressed ubiquitously, while ACTC1 is expressed mainly in cardiac cells. Although bacteria lack the eukaryotic cytoskeletal organization, the bacterial MreB gene bears recognizable sequence similarity to mammalian actin genes and codes for a protein that is similar to actin in structure and function. Which of the following statements is true about these genes?