BIO 123N – Old Dominion University – Exam 3 Study Guide
and Key Concepts
T/F: Viruses do not reduce crop and livestock production. - correct answer ✔✔ False
T/F: Viruses are particles that are inactive outside of their cells. - correct answer ✔✔ True
T/F: Some viruses cause cancer. - correct answer ✔✔ True
T/F: Software monitors internet searches and postings for viral symptoms and the geographical
location of each search/posting - correct answer ✔✔ True
T/F: The rabies virus manipulates the behavior of its host to increase its transmission - correct
answer ✔✔ True
What are metabolically-inactive virus particles that live outside of the host called? - correct
answer ✔✔ Virons
What is phage conversion? - correct answer ✔✔ The change in the phenotype of a lysogenic
bacterium cause by the prophage.
The genome of a virus is surrounded by what? - correct answer ✔✔ Capsid
What is a capsid? - correct answer ✔✔ Protein encasing the genome of a virus.
T/F: The virus genome is a single strand or a double strand. - correct answer ✔✔ True
, What is tissue trophism? - correct answer ✔✔ Viruses targeting a specific set of cells
T/F: Most viruses are significantly larger than a bacterium. - correct answer ✔✔ False
What must be provided by the host cell for viruses to replicate? - correct answer ✔✔
Energy(ATP,GTP), amino acids, carbs, phospholipids, nucleotides, DNA/RNA polymerase
enzymes, Ribosomes, tRNAs...
What kind of virus structure looks rodlike or threadlike? - correct answer ✔✔ Helical
What is a retrovirus? - correct answer ✔✔ A virus that has an RNA genome that is reverse-
transcribed into DNA by the enzyme reverse transcriptase
T/F: Viruses can replicate outside of their host. - correct answer ✔✔ False
What is a ligand? - correct answer ✔✔ A signal recognized by a receptor.
T/F: A virus can recognize and enter any type of cell. - correct answer ✔✔ False
T/F: The stable capsid of some viruses enable them to persist outside of the host cell for years. -
correct answer ✔✔ True
What is the first step of the virus life cycle? - correct answer ✔✔ Entering the host and
uncoating the virus to release viral contents into host cell
What is the second step of the virus life cycle? - correct answer ✔✔ Replication of the host cells
containing the viral particles
and Key Concepts
T/F: Viruses do not reduce crop and livestock production. - correct answer ✔✔ False
T/F: Viruses are particles that are inactive outside of their cells. - correct answer ✔✔ True
T/F: Some viruses cause cancer. - correct answer ✔✔ True
T/F: Software monitors internet searches and postings for viral symptoms and the geographical
location of each search/posting - correct answer ✔✔ True
T/F: The rabies virus manipulates the behavior of its host to increase its transmission - correct
answer ✔✔ True
What are metabolically-inactive virus particles that live outside of the host called? - correct
answer ✔✔ Virons
What is phage conversion? - correct answer ✔✔ The change in the phenotype of a lysogenic
bacterium cause by the prophage.
The genome of a virus is surrounded by what? - correct answer ✔✔ Capsid
What is a capsid? - correct answer ✔✔ Protein encasing the genome of a virus.
T/F: The virus genome is a single strand or a double strand. - correct answer ✔✔ True
, What is tissue trophism? - correct answer ✔✔ Viruses targeting a specific set of cells
T/F: Most viruses are significantly larger than a bacterium. - correct answer ✔✔ False
What must be provided by the host cell for viruses to replicate? - correct answer ✔✔
Energy(ATP,GTP), amino acids, carbs, phospholipids, nucleotides, DNA/RNA polymerase
enzymes, Ribosomes, tRNAs...
What kind of virus structure looks rodlike or threadlike? - correct answer ✔✔ Helical
What is a retrovirus? - correct answer ✔✔ A virus that has an RNA genome that is reverse-
transcribed into DNA by the enzyme reverse transcriptase
T/F: Viruses can replicate outside of their host. - correct answer ✔✔ False
What is a ligand? - correct answer ✔✔ A signal recognized by a receptor.
T/F: A virus can recognize and enter any type of cell. - correct answer ✔✔ False
T/F: The stable capsid of some viruses enable them to persist outside of the host cell for years. -
correct answer ✔✔ True
What is the first step of the virus life cycle? - correct answer ✔✔ Entering the host and
uncoating the virus to release viral contents into host cell
What is the second step of the virus life cycle? - correct answer ✔✔ Replication of the host cells
containing the viral particles
