Animal Replication

Question 1

tropism

Answer 1

specificity of a virus to a particular tissue/cell type

Question 2

Animal Virus Entry

fusion

Answer 2

some enveloped viruses leave their envelopes at the host cell membrane during entry or at the endosome following receptor mediated endocytosis

Question 3

Animal Virus Entry

receptor mediated endocytosis

Answer 3

membrane invagination pulls the virus into the cell in an endosome

Question 4

Animal Virus Entry

uncoating

Answer 4

process of removing the nucleocapsid can occur due to enzymes/pH changes in the endosome or following the escape from the endosome

Question 5

Animal Virus Release: Budding and lysis

host cell lysis

Answer 5

viral proteins puncture the host plasma membrane

Question 6

Animal Virus Release: Budding and lysis

budding

Answer 6

often occurs at the same time as envelope formation

Question 7

Double-Stranded (ds) DNA virus synthesis

tegument

Answer 7

layer of proteins between nucleocapsid and envelope

Question 8

Double-Stranded (ds) DNA virus synthesis

productive infection

Answer 8

lyse cell releasing 50,000 - 200,000 virions

Question 9

Double-Stranded (ds) DNA virus synthesis

latent infection

Answer 9

• virions are undetected can be reactivated after months/years
• different than a chronic infection

Question 10

Double-Stranded (ds) DNA virus synthesis

chronic infection

Answer 10

a slow increase in viral load

Question 11

Understanding RNA Viruses

Sense (+) RNA strands

Answer 11

can be used as mRNA

Question 12

Understanding RNA Viruses

Anti-Sense (-) RNA strands

Answer 12

must be transcribed into sense (+) RNA prior to translation, serve as the template for sense (+) synthesis

Question 13

Understanding RNA Viruses

RNA-dependent RNA polymerase

Answer 13

almost all RNA viruses (except retroviruses) require a virally encoded enzyme to transcribe and replicate RNA

Question 14

Understanding RNA Viruses

replicase

Answer 14

RdRp that replicates a viral RNA genome (more error prone than DdDp)

Question 15

Understanding RNA Viruses

transcriptase

Answer 15

an RdRp that synthesizes mRNA

Question 16

Sense (+) RNA Virus Synthesis

nonstructural proteins (NSP)

Answer 16

include enzymes for viral processes

Question 17

Sense (+) RNA Virus Synthesis

structural proteins (SP)

Answer 17

include spike proteins

Question 18

Sense (+) RNA Virus Synthesis

accessory proteins (AP)

Answer 18

involved in interfering with cellular processes and the innate immune response

Question 19

Sense (+) RNA Virus Synthesis

spike glycoprotein

Answer 19

associates with the ACE2 receptor and is cleaved to induce fusion

Question 20

Antisense (-) RNA Virus Synthesis

hemagluttinin spikes (HA)

Answer 20

attaches to sialic acid moieties linked to glycoproteins and glycolipids on cells in teh respiratory epithelium

Question 21

Antisense (-) RNA Virus Synthesis

neuraminidase spike (NA)

Answer 21

facilitates induction of receptor mediated endocytoosis and separation of the virus from the host cell during budding

Question 22

Retrosviruses

reversetranscriptase (RT)

Answer 22

• converts ssRNA into dsDNA
• functions as RpDp, DdDp, and a ribonuclease

Question 23

Retroviruses

integrase

Answer 23

inserts viral dsDNA into the host chromosome

Question 24

dsDNA Virus

Location of Nucleic Acid Synthesis.

Answer 24

nucleus

Question 25

# dsDNA Virus Steps of viral nucleic acid synthesis.

Answer 25

dsDNA --> dsDNA

Question 26

# dsDNA Virus Steps of viral protein synthesis.

Answer 26

dsDNA --> mRNA --> protein

Question 27

# dsDNA Virus Special viral enzymes involved.

Answer 27

N/A (usually)

Question 28

# dsRNA Virus Location of nucleic acid synthesis.

Answer 28

cytoplasm

Question 29

# dsRNA Virus Steps of viral nucleic acid synthesis.

Answer 29

dsRNA --> ssRNA --> dsRNA

Question 30

# dsRNA Virus Steps of viral protein synthesis.

Answer 30

dsRNA --> mRNA --> protein

Question 31

# dsRNA Virus Special viral enzymes involved.

Answer 31

RNA-dependent RNA polymerase (RdRp)

Question 32

# +ssRNA Virus Location of nucleic acid synthesis.

Answer 32

cytoplasm

Question 33

# +ssRNA Virus Steps in viral nucleic acid synthesis.

Answer 33

+RNA --> -RNA --> +RNA

Question 34

# +ssRNA Virus Steps of viral protein synthesis.

Answer 34

+RNA --> Protein +RNA --> -RNA --> +RNA --> Protein

Question 35

# +ssRNA Virus Special viral enzymes involved.

Answer 35

RNA-dependent RNA polymerase (RdRp)

Question 36

# -ssRNA Virus Location of nucleic acid synthesis

Answer 36

cytoplasm - influenza goes into the nucleus

Question 37

# -ssRNA Virus Steps of viral nucleic acid synthesis.

Answer 37

-RNA --> +RNA --> -RNA

Question 38

# -ssRNA Virus Steps of viral protein synthesis.

Answer 38

-RNA --> mRNA --> protein

Question 39

# -ssRNA Virus Special viral enzymes involved.

Answer 39

RNA-dependent RNA polymerase (RdRp)

Question 40

# Retrovirus Location of nucleic acid synthesis.

Answer 40

RNA --> DNA = cytoplasm DNA integration = nucleus

Question 41

# Retrovirus Steps of viral nucleic acid synthesis.

Answer 41

+RNA --> ssDNA --> dsDNA --> +RNA

Question 42

# Retrovirus Steps of viral protein synthesis.

Answer 42

DNA --> mRNA --> protein

Question 43

# Retrovirus Special viral enzymes involved.

Answer 43

- reverse transcriptase - integrase

Question 44

# Detrimental Outcomes of Viral Infection in Animals cytocidal infection

Answer 44

disease in which some of the symptoms result from cell death

Question 45

# Detrimental Outcomes of Viral Infection in Animals persistent/chronic infection

Answer 45

the cell is not lysed but instead remains a viral factory

Question 46

# Detrimental Outcomes of Viral Infection in Animals cytopathic effects (CPEs)

Answer 46

micorscopic or macroscopic changes or abnormalities in host cells and tissues that are distinct from lyses

Question 47

# Detrimental Outcomes of Viral Infection in Animals latency

Answer 47

viral genomes can be maintained in cells without virion production as proviruses or extrachromasomal elements

Question 48

# Detrimental Outcomes of Viral Infection in Animals oncogenic

Answer 48

capable of inducing cancer

Question 49

# Detrimental Outcomes of Viral Infection in Animals cytokines

Answer 49

soluble, low molecular weight protein or glycoprotein that acts as an intercellular signaling molecule

Question 50

# Detrimental Outcomes of Viral Infection in Animals cytokine storms

Answer 50

proinflammatory cytokines cause dilation of blood vessels that cause a rapid drop on blood pressure leading to shock

Question 51

# How Do We Fight Viral Infections? innate immunity

Answer 51

parts of the immune response that: - has no memory - is non-specific - doesn't improve due to previous infection

Question 52

# How Do We Fight Viral Infections?: Innate Immunity complement proteins

Answer 52

can surround viruses in a process called opsonization promoting phagocytosis and disrupt viral enzymes

Question 53

# How Do We Fight Viral Infections?: Innate Immunity Natural Killer (NK) cells

Answer 53

destroy virally infected cells by inducing apoptosis - looks for absence of MHC I self-recognition signal on cells

Question 54

# How Do We Fight Viral Infections?: Innate Immunity Interferons

Answer 54

cytokines produced by infected cells which induce expression of anti-viral pathways in neighboring cells

Question 55

# How Do We Fight Viral Infections? adaptive immunity

Answer 55

parts of the immune response that: - are specific to a particular pathogen - induce memory response - improve due to previous infection

Question 56

# How Do We Fight Viral Infections?: Adaptive Immunity neutralizing antibodies

Answer 56

proteins that bind to antigens, can block attachment of a virus to host cells and tag the cirus for destruction by phagocytes

Question 57

# How Do We Fight Viral Infections?: Adaptive Immunity cytotoxic T cells

Answer 57

interact with MHC I self recognition signals to 'check' cellular trash for signs of abnormalities, inducing apoptosis in infected and cancerous cells

Question 58

# How Do We Fight Viral Infections? neuraminidase inhibitors

Answer 58

treat influeanze by inhibiting the enzymatic activity of NA spikes, which aid in envelop separation

Question 59

# How Do We Fight Viral Infections? nucleoside or mononucleotide analogues

Answer 59

inhibit DNA viruses which use their own enzyme to phosphorylate nucleotides

Question 60

# How Do We Fight Viral Infections? Nucleoside reverse transcriptase inhibitors (NRTIs)

Answer 60

inhibit retroviruses through incorporation into DNA during reverse transcriptase which halts synthesis

Question 61

# How Do We Fight Viral Infections? Nonnucleotide reverse transcriptase inhibitors (NNRTIs)

Answer 61

prevent DNA synthesis by binding to and inhibiting reverse transcriptase

Question 62

# How Do We Fight Viral Infections? protease inhibitors

Answer 62

block HIV protease which is required for viral protein production

Question 63

# How Do We Fight Viral Infections? integrase inhibitors

Answer 63

inhibit DNA incorporation into genome

Question 64

# How Do We Fight Viral Infections? fusion inhibitors

Answer 64

prevent entry