Microbiology Worksheet 9
Which does not refer to the shape of a virus?
Bacillus
The nucleocapsid is composed of
DNA or RNA, and protein.
Which is a filamentous phage?
M13
What part of the attached bacteriophage enters through the host cell wall?
The nucleic acid.
Prions
are made of protein only.
The correct order for the stages of a phage infection is
attachment, penetration, transcription, replication of nucleic acid and protein, assembly, release.
Viruses that infect bacteria are referred to as
bacteriophages.
The shape of the virus is determined by its
capsid.
If the infecting phage lacks some critical pieces of DNA necessary for replication, it is called
defective.
The viral envelope closely resembles the
eukaryotic cytoplasmic membrane.
The enveloped viruses typically obtain their envelope
from the host cytoplasmic membrane as they exit the host.
Enveloped viruses
have a lipid bilayer membrane containing various proteins.
Assembly of the T4 phage
may involve some self-assembly AND may involve the use of scaffolds.
Outside of living cells, viruses are
metabolically inert.
Using phages to treat a bacterial infection is an interesting idea because
of the increasing problem of antibiotic resistance in pathogens.
A limiting factor for viral infection of animals cells is
presence of specific receptor molecules on the host cell.
Phage-encoded enzymes are
produced in a sequential manner AND are used to customize the cell for viral production.
The protein projections on the surface of a virus that are involved in attachment to the host cell are called
spikes.
Viroids characteristically are composed of
ssRNA.
Phages that can either replicate and cause cell lysis or can integrate their DNA into the host DNA are called
temperate phages.
The integration of phage DNA into the bacterial chromosome occurs because of
the phage's ability to synthesize an enzyme that integrates its DNA into the host's chromosome.
Retroviruses are unique in that they
use RNA as a template to make DNA.
A phage that replicates inside the host cell and then lyses its host during its release is a
virulent or lytic phage.
