Viruses, Bacteriophages, and Prions

These flashcards cover key concepts related to the structure and life cycles of viruses, bacteriophages, and prions, helping to reinforce knowledge for the exam.

A virion's genetic material can be either or .

DNA or RNA.

The __ is the protective protein shell that encloses the genetic material of a virion.

Capsid.

Some virions have a __ derived from the host cell's membrane.

Lipid bilayer.

__ are structures that can stick out from the envelope or capsid of a virus.

Protein spikes.

The two cycles of bacteriophage infection are __ and __

Lytic and Lysogenic.

In the lytic cycle, viral proteins modify the __ of the host cell.

Physiology.

The first step of the lytic cycle involves proteins on the capsid binding to __ on the bacterial membrane.

Receptors.

During the lytic cycle, the phage __ opens a hole in the bacterial cell wall.

Lyzosome.

The lysogenic cycle begins when the bacteriophage attaches to the surface of the __ cell.

Bacterial.

The viral DNA becomes a __ when it is incorporated into the host cell’s chromosome during the lysogenic cycle.

Prophage.

In the lysogenic cycle, the prophage replicates with the host cell's __.

DNA.

A loss of the repressor signal activates the __ phase of the virus.

Lytic.

Lytic cycle results in the immediate __ of the bacteriophage.

Replication.

Chronic infections lead to continuous release of virus particles at __ levels.

Low.

Latent infections, like chicken pox, refer to viruses that are __ for a time.

Dormant.

Plant viruses can enter their host through __ in the plant.

Wounds.

The Sputnik virus infects the giant __ by hijacking its replication machinery.

Mimivirus.

To replicate, virophages like Sputnik rely on the __ of the Mimivirus.

Replication machinery.

Viroids are RNA viruses that lack __.

Capsids

Prions are misfolded __ that can induce other proteins to misfold.

Proteins.

A misfolded prion can act as a __ for normal proteins, forcing them to misfold.

Template.

Misfolded proteins can aggregate into insoluble clumps that damage __ tissue.

Brain.

The entry of plant viruses into cells typically occurs through __.

Wounds.

The assembly of new virophage particles takes place before the host cell __.

Lyses.

Acute infections typically involve __ infection events and often result in host death.

One.

During the lytic cycle, host cells make __ proteins as directed by the viral genome.

Capsid.

In the lysogenic cycle, a repressor prevents the virus's DNA from being __.

Excised.

Viral DNA that is incorporated into a host's chromosome is said to be __.

Dormant.

PrPSc is a term used for misfolded __ associated with prions.

Proteins.

During viral infections, __ synthesis involves both DNA and protein production.

Viral replication

For an animal virus, the first step of infection is __ to the host cell.

Attachment.

The __ cycle of a bacteriophage leads to the destruction of the host cell.

Lytic.

New viral particles are released from the host cell during the process of __.

Release.

Chronic infections can last for a __ period of time with continuous virus release.

Long.

A bacteriophage's injection of genetic material occurs after binding to the bacterial __.

Membrane.

The __ of a virus is often characterized by its ability to replicate passively with host cell division in the lysogenic cycle.

Life cycle.

In the lytic cycle, viral genome replication occurs after the host cell's __ is modified.

Physiology.

The __ cycle integrates viral DNA into the host genome, while the lytic cycle does not.

Lysogenic.

Prions are unique in that they replicate by inducing other normal proteins to __.

Misfold.

In plant infections, how viruses spread throughout the plant is by passing from one cell to __.

Another.