Virology Exam 1 Quiz questions

The spike protein of coronavirus has two domains. Which of these is primarily responsible for host binding? a) S1 b) S2 c) ACE2 d) SA

A

Which of the following are NOT a characteristic of viral nucleic acids? a) They are always circular. b) They can be double stranded or single stranded. c) They are stored in the capsid or nucleocapsid. d) They are used to classify viruses.

A

Which of the following statements is true? a) Different virus species can use the same receptors. b) Receptors are only on cells so viruses can recognize them. c) Viruses within a family always use the same receptor. d) Viruses only use the overall structure of a receptor to recognize its host.

A

Which viral protein is used to bind to the CD4 receptor? a) Gp120 b) Heparin sulfate c) Hemaglutinin d) CCR5

A

Viruses are defined as obligate intracellular parasites because ... a) They cannot reproduce on their own. b) They cannot metabolize on their own. c) They respond to stimuli. d) They can evolve.

A and B

Which of the following is a distinct step in the reverse transcription of retroviral RNA? a) Initiation of (+) DNA synthesis b) Initiation of synthesis of new template RNAs c) Template exchange d) Nicking of the template RNA

A and C

Which of the following are ways in which viruses have benefited society? a) New scientific techniques b) Infecting plants c) Rescuing the human genome d) Curing disease

A and D

Which of the following must occur in order for viral envelopes to fuse with cellular membrane during entry? a) The fusion protein must undergo a conformational change. b) The virus must bind to its host cellular receptor. c) The cellular membrane must ruffle. d) The viral and cellular membranes must be pulled together.

A, B, and D

Viral genomes encode proteins involved in ... a) Assembly b) Energy Production c) Regulation of replication d) Replication e) Lipid synthesis

A, C, and D

A cell that has a functional receptor for a virus but may or may not support viral replication is called ... a) Infected b) Susceptible c) Resistant d) Promiscuous

B

Antigenic drift refers to ... a) Large changes that occur when multiple related viruses infect the same cell. b) Small changes that accumulate in viral genomes during replication. c) Variability in viral genomes, even within a species. d) Different segments getting packaged into the same viral particle.

B

The term for the one long protein that results from the translation of the picornavirus genome is ... a) a precleaved protein b) a polyprotein c) a polycistronic message

B

Which detection method is best for early detection of HIV? a) RNA/DNA tests that detect viral genomes. b) Antibody-Antigen tests that detect the virus in the blood. c) Antibody tests that detect the immune response made to the virus.

B

Which of the following retrovirus proteins are generated from a spliced RNA? a) Polymerase proteins b) Envelope proteins c) Gag proteins

B

Which viral enzyme is directly involved in incorporating HIV DNA into the host chromosome? a) RNA-dependent RNA polymerase b) Integrase c) Protease d) Reverse Transcriptase

B

Which of the following viruses forms a pore in the endosomal membrane in order to release its nucleic acid into the cytoplasm? a) Dengue virus b) Norovirus c) Influenza virus d) Adenovirus e) Poliovirus

B and E

Which of the following statements are true for Zika virus? a) it is primarily vectored by rats b) it is a flavivirus c) it is primarily vectored by mosquitoes d) it is enveloped

B, C, and D

At an MOI = 1, which of the following statements is correct? a) There will be no eclipse period in the growth curve. b) Only 1% of the cells in the culture will be infected. c) On average, approximately 1 virus was added per 1 target cell. d) All of the above.

C

In which way is the retrovirus HIV, unlike other single stranded (+) RNA viruses? a) Retroviruses are smaller than all other ss (+) RNA viruses. b) Retrovirus RNA gets transcribed in the cytoplasm. c) Retroviruses encode an RNA transcriptase to convert their RNA to DNA. d) Retroviruses are enveloped while other ss (+) RNA viruses are not.

C

The first vaccine was developed to prevent ... a) Rabies b) Chickenpox c) Smallpox d) Measles

C

Which of the following is not a class of viral genomes? a) (-) ssRNA b) (+) ssRNA c) Gapped dsRNA d) Gapped dsDNA e) dsDNA

C

Which of the following statements is true of all viruses? a) They are all enveloped. b) They all possess the same type of nucleic acid. c) They all have a protein capsid that encases their genetic material. d) All of the above.

C

Which of the following steps is found in Dengue virus replication but not Poliovirus replication? a) The production of a (-) sense RNA intermediate b) The production of (-) sense RNA using an RNA-dependent RNA polymerase c) The viral RNA forms a circle prior to joining with the replication complex d) Cleavage of viral proteins by a viral protease

C

The protein structure surrounding the viral nucleic acid is called what?

Capsid

Prolate is a viral shape variant found in ... a) Mammalian viruses b) Plant viruses c) Retroviruses d) Bacteriophages e) Human viruses

D

Viral envelopes have which proteins sticking out of them? a) RdRp b) Capsomers c) Glycogen d) Glycoproteins

D

Which statement is false? a) The budding process is driven by the formation of matrix and capsid proteins forming a new viral particle underneath the cellular membrane where envelope proteins are embedded. b) The protease cleaves the gag proteins within the viral particle to from the final capsid structure. c) The gag-pol complex has viral enzymes bound to it for packaging. d) Maturation of the HIV virus occurs before the virus buds off from the host cell.

D

Capsids are important for which of these processes? a) Attachment to the host cell b) Entry into the host cell c) Packaging of viral nucleic acid d) Protecting the genome e) Transporting the genome f) All of the above

F

(T/F) All (+) RNA is mRNA.

False

(T/F) Capsomers are the most complex organization of virus capsids.

False

(T/F) Coronavirus genomes are pretty small for ss (+) RNA viruses.

False

(T/F) During attachment, the strongest interaction is between a virus and its adhesion receptor.

False

(T/F) Influenza was discovered before the first oncogenic virus was discovered.

False

(T/F) Robert Koch's discoveries helped Louis Pasteur develop Germ Theory.

False

(T/F) VPs are the most complex organization of virus capsids.

False

(T/F) Viruses with RNA genomes use cellular enzymes to directly make mRNA.

False

"Virus" comes from the latin word for what?

Poison

For ss (+) RNA viruses, which protein is responsible for copying the genome?

RNA-dependent RNA polymerase

RdRp stands for ...

RNA-dependent RNA polymerase

What is the most common mode of transmission for HIV?

Sexual contact or intercourse

(T/F) Both carbohydrates and protein receptors on host cells can be used by viruses as attachment receptors.

True

(T/F) In dsRNA genomes, the positive strand of RNA can be directly used as mRNA.

True

(T/F) Lowered internal pH is a major different between endosomes and caveosomes.

True

(T/F) Retroviruses differ from other ss (+) RNA viruses in that their genomes are NOT directly translated into proteins.

True

(T/F) Viral genome size and capsid size are related.

True

(T/F) Viruses can be classified by the type of viral genome they posses.

True

(T/F) Viruses with DNA genomes can use cellular enzymes to make mRNA.

True

Every replication cycle leads to the making of what type of nucleic acid?

mRNA