Molecular Biology of the Cell, 7th Edition by Bruce Alberts, Rebecca Heald
Alexander Johnson
Topic 1: Cells and Genomes (Questions 1-20)
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.
Answer: C
Rationale: All known cellular life uses ATP as its primary energy currency. While
many cells have a nucleus (eukaryotes), bacteria and archaea (prokaryotes) do
,not. Many organisms are heterotrophs and do not obtain energy directly from
sunlight. Some bacteria have very small genomes (e.g., Mycoplasma has ~500
genes).
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.
Answer: E
Rationale: These are universal properties of life. All cells must exchange materials
across their membrane (A), translate mRNA into proteins using ribosomes (B), and
,replicate (C) and transcribe (D) their genetic information using templated
polymerization.
3. 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
Answer: C
Rationale: Diffusion is a passive process driven by the random thermal motion of
molecules and the concentration gradient. It does not require an input of free
, energy (like ATP hydrolysis). All other listed processes are active, energy-requiring
processes .
4. 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
Answer: C
Rationale: Bacteria are prokaryotes and do not contain membrane-bound
organelles like mitochondria. ATP production in bacteria occurs on the plasma
membrane and within the cytoplasm. They can have flagella (A), cell walls (B),
ribosomes (D), and can exchange DNA via conjugation (E) .
Alexander Johnson
Topic 1: Cells and Genomes (Questions 1-20)
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.
Answer: C
Rationale: All known cellular life uses ATP as its primary energy currency. While
many cells have a nucleus (eukaryotes), bacteria and archaea (prokaryotes) do
,not. Many organisms are heterotrophs and do not obtain energy directly from
sunlight. Some bacteria have very small genomes (e.g., Mycoplasma has ~500
genes).
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.
Answer: E
Rationale: These are universal properties of life. All cells must exchange materials
across their membrane (A), translate mRNA into proteins using ribosomes (B), and
,replicate (C) and transcribe (D) their genetic information using templated
polymerization.
3. 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
Answer: C
Rationale: Diffusion is a passive process driven by the random thermal motion of
molecules and the concentration gradient. It does not require an input of free
, energy (like ATP hydrolysis). All other listed processes are active, energy-requiring
processes .
4. 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
Answer: C
Rationale: Bacteria are prokaryotes and do not contain membrane-bound
organelles like mitochondria. ATP production in bacteria occurs on the plasma
membrane and within the cytoplasm. They can have flagella (A), cell walls (B),
ribosomes (D), and can exchange DNA via conjugation (E) .
