1 | P a g e | © copyright 2024/2025 | Grade A+
Microbiology Exam 2 uiowa Knudtson
Questions & 100% Correct Answers
What kind of cells can viruses infect?
✓ ~~> viruses infect every type of cell, including bacteria, algae, fungi,
protozoa, plant, and animals
Are viruses alive?
✓ ~~> two sides of the debate:
1. since viruses are unable to replicate independently from the host cell, so
no, not alive
2. even though viruses do not exhibit most of the life processes of cells, they
can direct them, so more than inert (lacking strength/ability to move) and
lifeless molecules
viruses are better described as active or inactive rather than dead or alive
What does it mean if a virus is described as inactive?
✓ ~~> cannot replicate
What does it mean if a virus is described as active?
Master01 | September, 2024/2025 | Latest update
, 2 | P a g e | © copyright 2024/2025 | Grade A+
✓ ~~> has the ability to get into a host cell and replicate and spread
What role do viruses play in evolution?
✓ ~~> infect cells and influence their genetic makeup
shape the way cells, tissues, bacteria, plants, and animals have evolved
10% of the human genome consits of sequences that come from viruses
10-20% of bacterial DNA contains viral sequences
What does it mean that viruses are obligate intracellular parasites?
✓ ~~> cannot multiply unless they invade a specific host cell and instruct
its genetic and metabolic machinery to make and release new viruses
What unit are viruses measured in?
✓ ~~> nanometers
What are the viral components?
✓ ~~> covering (capsid and maybe envelope)
central core (nucleic acid molecules, matric proteins, and maybe enzymes)
What is a capsid?
Master01 | September, 2024/2025 | Latest update
, 3 | P a g e | © copyright 2024/2025 | Grade A+
✓ ~~> protein shell that surrounds the nucleic acid
What is a nucleocapsid?
✓ ~~> the capsid together with the nucleic acid
What does the covering of naked viruses consist of?
✓ ~~> just a nucleocapsid
What is an envelope?
✓ ~~> external covering of a nucleocapsid, usually a modified piece of
the host's cell membrane
What are spikes?
✓ ~~> can be found on naked or enveloped viruses
project from the nucleocapsid or the envelope
allow viruses to dock with host cells
What is a virion?
✓ ~~> a fully formed virus that is able to establish as infection in a host
cell
Master01 | September, 2024/2025 | Latest update
, 4 | P a g e | © copyright 2024/2025 | Grade A+
What is the most prominent feature of viruses?
✓ ~~> the viral capsid
What is a viral capsid composed of?
✓ ~~> identical protein subunits called capsomere
How do capsomeres assemble into a viral capsid?
✓ ~~> capsomeres spontaneously self-assemble into the finished capsid
What are the three different orientations of capsomeres in a viral capsid?
✓ ~~> helical
icosahedral
complex
What do enveloped viruses take with them when they are released from a
host cell?
✓ ~~> they take a bit of the host's cell membrane
Where can enveloped viruses bud from?
✓ ~~> cell membrane
nuclear envelope
Master01 | September, 2024/2025 | Latest update
Microbiology Exam 2 uiowa Knudtson
Questions & 100% Correct Answers
What kind of cells can viruses infect?
✓ ~~> viruses infect every type of cell, including bacteria, algae, fungi,
protozoa, plant, and animals
Are viruses alive?
✓ ~~> two sides of the debate:
1. since viruses are unable to replicate independently from the host cell, so
no, not alive
2. even though viruses do not exhibit most of the life processes of cells, they
can direct them, so more than inert (lacking strength/ability to move) and
lifeless molecules
viruses are better described as active or inactive rather than dead or alive
What does it mean if a virus is described as inactive?
✓ ~~> cannot replicate
What does it mean if a virus is described as active?
Master01 | September, 2024/2025 | Latest update
, 2 | P a g e | © copyright 2024/2025 | Grade A+
✓ ~~> has the ability to get into a host cell and replicate and spread
What role do viruses play in evolution?
✓ ~~> infect cells and influence their genetic makeup
shape the way cells, tissues, bacteria, plants, and animals have evolved
10% of the human genome consits of sequences that come from viruses
10-20% of bacterial DNA contains viral sequences
What does it mean that viruses are obligate intracellular parasites?
✓ ~~> cannot multiply unless they invade a specific host cell and instruct
its genetic and metabolic machinery to make and release new viruses
What unit are viruses measured in?
✓ ~~> nanometers
What are the viral components?
✓ ~~> covering (capsid and maybe envelope)
central core (nucleic acid molecules, matric proteins, and maybe enzymes)
What is a capsid?
Master01 | September, 2024/2025 | Latest update
, 3 | P a g e | © copyright 2024/2025 | Grade A+
✓ ~~> protein shell that surrounds the nucleic acid
What is a nucleocapsid?
✓ ~~> the capsid together with the nucleic acid
What does the covering of naked viruses consist of?
✓ ~~> just a nucleocapsid
What is an envelope?
✓ ~~> external covering of a nucleocapsid, usually a modified piece of
the host's cell membrane
What are spikes?
✓ ~~> can be found on naked or enveloped viruses
project from the nucleocapsid or the envelope
allow viruses to dock with host cells
What is a virion?
✓ ~~> a fully formed virus that is able to establish as infection in a host
cell
Master01 | September, 2024/2025 | Latest update
, 4 | P a g e | © copyright 2024/2025 | Grade A+
What is the most prominent feature of viruses?
✓ ~~> the viral capsid
What is a viral capsid composed of?
✓ ~~> identical protein subunits called capsomere
How do capsomeres assemble into a viral capsid?
✓ ~~> capsomeres spontaneously self-assemble into the finished capsid
What are the three different orientations of capsomeres in a viral capsid?
✓ ~~> helical
icosahedral
complex
What do enveloped viruses take with them when they are released from a
host cell?
✓ ~~> they take a bit of the host's cell membrane
Where can enveloped viruses bud from?
✓ ~~> cell membrane
nuclear envelope
Master01 | September, 2024/2025 | Latest update
