BIOL 351 Exam 4 Questions & Answers 2026 | Complete
Study Guide | Graded A+
1. What is the minimum number of genes required for a cell to be considered
viable?
Approximately 300 genes
Approximately 100 genes
Approximately 200 genes
Approximately 500 genes
2. What is the primary goal of genome annotation?
Confirming experimental data
Identifying known genes and regulatory sequences
Creating a physical map of the genome
Encoding the genome with A,T,C, and G
3. A researcher is attempting to replicate DNA in vitro. All necessary
components are added, however, the DNA that is used does not have a free
3' hydroxyl. What kind of result is expected?
The DNA will replicate at a normal rate
The DNA will not replicate because DNA polymerase will not be
active
The DNA will replicate but at a much slower rate
The DNA will not replicate because DNA polymerase can not add
dNTPs to the existing DNA
The DNA will not replicate because the free 3'hydroxyl is what
catalyzes the DNA synthesis
,4. What is the general trend in gene content as genome size increases?
Gene content fluctuates unpredictably.
Gene content decreases.
Gene content remains constant.
Gene content typically increases.
5. If a mutation in the T7 phage genome prevents the formation of concatemers,
what would be the likely impact on phage replication?
Phage replication would be impaired, leading to reduced
production of viral particles.
Phage replication would result in the production of only single
genomes.
Phage replication would occur normally, but with altered protein
synthesis.
Phage replication would increase due to enhanced genome stability.
6. The protein that maintains the LYSOGENIC cycle of λ is
trypsin
RNase
RecA
λ repressor
7. What are the structural characteristics of concatemers produced by T7
phage?
Single-stranded RNA
Circular plasmids
, Linear proteins
Concatenated DNA molecules
8. What is the name of the protein produced when sufficient lambda genome is
synthesized?
RNA polymerase
Lysogenic protein
Capsid protein
Lambda repressor
9. Describe the significance of primers in the process of DNA replication.
Primers are involved in the repair of DNA during replication.
Primers help in the separation of the two DNA strands.
Primers are used to unwind the DNA strands before replication.
Primers are essential because they provide the necessary starting
point for DNA polymerase to begin synthesis.
10. If a mutation occurs in the CI protein that prevents it from functioning, what
would be the likely outcome for the lambda phage?
The phage would stop replicating altogether.
The phage would become unable to infect host cells.
The phage would remain in the lysogenic state indefinitely.
The phage would likely enter the lytic cycle.
11. Describe the significance of gene size variation among prokaryotic
organisms.
, Gene size is uniform across all prokaryotic organisms.
Larger genes are always associated with more complex organisms.
Gene size variation can indicate differences in metabolic
capabilities and evolutionary adaptations among prokaryotic
organisms.
Gene size does not affect the function of the organism.
12. Describe how protelomerases contribute to the lifecycle of a phage.
Protelomerases replicate proteins necessary for phage assembly.
Protelomerases degrade host cellular DNA to facilitate phage entry.
Protelomerases are enzymes that process the ends of linear DNA,
which is crucial for the stability and replication of phage genomes.
Protelomerases synthesize RNA to aid in protein production.
13. What type of organisms are known to have the largest genes among
prokaryotes?
Viruses
Archaea
Some bacteria
Eukaryotes
14. What is the term for the process that allows a virus to enter the lytic cycle
from a lysogenic state?
Translation
Transcription
Induction
Study Guide | Graded A+
1. What is the minimum number of genes required for a cell to be considered
viable?
Approximately 300 genes
Approximately 100 genes
Approximately 200 genes
Approximately 500 genes
2. What is the primary goal of genome annotation?
Confirming experimental data
Identifying known genes and regulatory sequences
Creating a physical map of the genome
Encoding the genome with A,T,C, and G
3. A researcher is attempting to replicate DNA in vitro. All necessary
components are added, however, the DNA that is used does not have a free
3' hydroxyl. What kind of result is expected?
The DNA will replicate at a normal rate
The DNA will not replicate because DNA polymerase will not be
active
The DNA will replicate but at a much slower rate
The DNA will not replicate because DNA polymerase can not add
dNTPs to the existing DNA
The DNA will not replicate because the free 3'hydroxyl is what
catalyzes the DNA synthesis
,4. What is the general trend in gene content as genome size increases?
Gene content fluctuates unpredictably.
Gene content decreases.
Gene content remains constant.
Gene content typically increases.
5. If a mutation in the T7 phage genome prevents the formation of concatemers,
what would be the likely impact on phage replication?
Phage replication would be impaired, leading to reduced
production of viral particles.
Phage replication would result in the production of only single
genomes.
Phage replication would occur normally, but with altered protein
synthesis.
Phage replication would increase due to enhanced genome stability.
6. The protein that maintains the LYSOGENIC cycle of λ is
trypsin
RNase
RecA
λ repressor
7. What are the structural characteristics of concatemers produced by T7
phage?
Single-stranded RNA
Circular plasmids
, Linear proteins
Concatenated DNA molecules
8. What is the name of the protein produced when sufficient lambda genome is
synthesized?
RNA polymerase
Lysogenic protein
Capsid protein
Lambda repressor
9. Describe the significance of primers in the process of DNA replication.
Primers are involved in the repair of DNA during replication.
Primers help in the separation of the two DNA strands.
Primers are used to unwind the DNA strands before replication.
Primers are essential because they provide the necessary starting
point for DNA polymerase to begin synthesis.
10. If a mutation occurs in the CI protein that prevents it from functioning, what
would be the likely outcome for the lambda phage?
The phage would stop replicating altogether.
The phage would become unable to infect host cells.
The phage would remain in the lysogenic state indefinitely.
The phage would likely enter the lytic cycle.
11. Describe the significance of gene size variation among prokaryotic
organisms.
, Gene size is uniform across all prokaryotic organisms.
Larger genes are always associated with more complex organisms.
Gene size variation can indicate differences in metabolic
capabilities and evolutionary adaptations among prokaryotic
organisms.
Gene size does not affect the function of the organism.
12. Describe how protelomerases contribute to the lifecycle of a phage.
Protelomerases replicate proteins necessary for phage assembly.
Protelomerases degrade host cellular DNA to facilitate phage entry.
Protelomerases are enzymes that process the ends of linear DNA,
which is crucial for the stability and replication of phage genomes.
Protelomerases synthesize RNA to aid in protein production.
13. What type of organisms are known to have the largest genes among
prokaryotes?
Viruses
Archaea
Some bacteria
Eukaryotes
14. What is the term for the process that allows a virus to enter the lytic cycle
from a lysogenic state?
Translation
Transcription
Induction
