Exam 1 With 100% Correct And Verified Answers 2024, Exams of Advanced Education

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GMS 6121 Exam 1 With 100% Correct And Verified Answers 2024 The 4 things that viruses lack - Correct Answer-(1) Enzymes that produce basic chemical building blocks (2) Enzyme systems that generate usable energy (3) Enzymes/tRNAs/ribosomes that direct protein synthesis (4) Membranes that concentrate and localize key molecules All viruses have _______ and _______, while only some viruses have ________. - Correct Answer-nucleic acids and a capsid; an envelope A ________ is a complete, infectious virus particle. - Correct Answer-virion Naked capsids are ______ to drying, heat, detergents, and acid. - Correct Answer-resistant Enveloped capsids are ________ to drying, heat, detergents, and acid. - Correct Answer-sensitive General stages of virus infection - Correct Answer-1) Adsorption 2) Entry 3) Uncoating 4) Early genes 5) Replication 6) Late genes 7) Assembly 8) Packaging 9) Release Immunofluorescence - Correct Answer-method that uses virus-specific antibodies to detect a specific viral protein, usually in a tissue section biopsy or cells from fluid ELISA (enzyme-linked immunosorbent assay) - Correct Answer-method that uses virus-specific antibodies to detect virus particles or secreted viral proteins in fluid Electron microscopy - Correct Answer-method used to detect viral particles in lesions Cytopathic effects include: - Correct Answer--Cell lysis -Rounding (or other morphological changes) -Syncytia -Inclusion bodies Transformed cells display one or more of these changes: - Correct Answer-- Loss of anchorage dependence -Loss of contact inhibition -Colony formation -Immortalization -Tumor formation in immunocompromised mice Why do virus preps have such low infectivity? - Correct Answer--Not all virus particles are intact -Virus particles can contain defective genomes -Virus particles can be empty -Cells have antiviral defense mechanisms Serology - Correct Answer-the diagnostic detection of antibodies in serum, to measure the immune response to viral infection Antibodies to virus proteins are generated by _____ in response to infection. - Correct Answer-B cells Pathogenesis - Correct Answer-the process by which one organism causes disease in another The majority of viral infections are __________. - Correct Answer-subclinical Two components of viral disease: - Correct Answer--Effects of virus replication on the host -Effects of host response on virus and the host Tamiflu is a ________ inhibitor. - Correct Answer-neuraminidase An example of a live attenuated vaccine is: - Correct Answer-polio vaccine. An example of a subunit vaccine is: - Correct Answer-Hep B vaccine The ____________ is the most common route of viral entry. - Correct Answer- respiratory tract Mechanical barriers to infection in the respiratory tract include: - Correct Answer--Mucus traps viruses -ciliary action propels viruses out of the lungs -sneezing -coughing Cellular barriers to infection in the respiratory tract include: - Correct Answer-macrophages in alveoli GMS 6121 Exam 1 With 100% Correct And Verified Answers 2024 Abortive infection - Correct Answer-A virus can inter a host cell but cannot generate infectious progeny Cell death from viral infection may result from: - Correct Answer--Diversion of cell's energy -Shutoff of host macromolecular synthesis -Competition of viral mRNAs for cellular ribosomes -Competition for cellular transcription factors Cell lysis in vivo results in release of ________. - Correct Answer-pyrogens Example of an abortive infection - Correct Answer-HPV Persistent infection - Correct Answer-No cell death and cells are not altered significantly in their growth habits Three types of persistent infections - Correct Answer--Chronic infections -Latent infections -Recurrent infections Transformation - Correct Answer-Virus infects and genetically alters a cell; result is abnormal cell growth Types of abnormal cell growth - Correct Answer--loss of contact inhibition -loss of polarization -immortalization -disruption of cell cytoskeleton Immortalization - Correct Answer-Cells replicate out of control ___________ encode an oncogene that blocks a cellular tumor suppressor gene. - Correct Answer-Papillomaviruses ________ integrate into host genomes and can disrupt cell cycle regulatory genes. - Correct Answer-Retroviruses What are the determinants of viral tropism? - Correct Answer--Accessibility of the permissive cell -Presence of appropriate cell surface receptors -Presence of intracellular host factors required for virus replication -Absence of suppressive antiviral mediators ________ release of virus facilitates virus dispersal. - Correct Answer-Apical _________ release of virus facilitates dissemination, providing access to underlying tissue. - Correct Answer-Basolateral Routes of dissemination - Correct Answer--Hematogenous spread -Neural spread ________ spread is the most effective, rapid, and common means of dissemination - Correct Answer-Hematogenous Primary viremia - Correct Answer-virus replicates at its primary site of infection Secondary viremia - Correct Answer-Virus is disseminated from primary site, through tissue, and then accesses the blood again. The amount of virus in the blood is higher in _______ viremia than in _______ viremia. - Correct Answer-secondary; primary Passive viremia - Correct Answer-results from virus introduced into blood without replication; virus does not replicate until it reaches target organ Active viremia - Correct Answer-Virus replication occurs preceding viremic phase Cell-associated hematogeneous spread - Correct Answer--May replicate in migratory cells, such as dendritic cells and lymphocytes, which move around the body via the bloodstream -May adhere to RBCs or platelets without replicating Neural spread - Correct Answer-Certain viruses spread from primary site of infection by entering local nerve endings Viruses can encode proteins that suppress IFN response by: - Correct Answer--blocking IFN induction -blocking IFN signaling -blocking IFN-induced antiviral proteins Types of immunopathology - Correct Answer--Viral induction of flu-like symptoms -Over-stimulation of the innate immune response -Antibody-dependent enhancement of infection (ADE) -Immunopathology via generation of immune complexes Immune complexes - Correct Answer-virions bound by specific antibody GMS 6121 Exam 1 With 100% Correct And Verified Answers 2024 What are the processes by which viruses naturally acquire genetic changes? - Correct Answer--Recombination -Reassortment For induced mutation, the goal is __________. - Correct Answer-single nucleotide changes Examples of chemical mutagens used in the lab - Correct Answer-- hydroxylamine -nitrous acid -alkylating agents Example of physical means of inducing mutation - Correct Answer-UV crosslinking Forward genetics identifies: - Correct Answer-the gene of interest Reverse genetics identifies: - Correct Answer-the function of the gene of interest Picornaviruses are ________ viruses with ______-sense RNA genomes. - Correct Answer-nonenveloped; positive Picornavirus translation is initiated by _________. - Correct Answer-internal ribosome entry site (IRES) Examples of picornaviruses - Correct Answer--Poliovirus -Hepatitis A viris -Foot-and-mouth disease virus (FMDV) -Rhinoviruses Picornavirus genome codes for a ___________. - Correct Answer-Polyprotein Picornaviruses have a(n) ________ structure comprised of ______ subunits. - Correct Answer-icosohedral; 60 The basic building block of a capsid is _________. - Correct Answer-protomer Poliovirus uses the receptor ___________. - Correct Answer-CD155 (Pvr) Most rhinoviruses use the receptor __________. - Correct Answer-ICAM-1 For poliovirus and rhinovirus, the receptor binding site is in/on _________. - Correct Answer-the canyon Capsid protein of astroviruses may function as an _________. - Correct Answer-enterotoxin Caliciviruses commonly bind _______. - Correct Answer-carbohydrates VPg at ____ end of calicivirus genomes acts as _________ to initiate translation. - Correct Answer-5' ; protein cap analogue ___________ is being investigated as a target of antiviral drug development. - Correct Answer-Norovirus RdRp Calicivirus VP2 is produced by _____________ on sg mRNA. - Correct Answer- translation termination-reinitiation (TTR) __________ is a significant cause of gastroenteritis outbreaks worldwide. - Correct Answer-Norovirus Different human __________ recognize different HBGAs. - Correct Answer- noroviruses Histo-blood group antigen (HBGA) - Correct Answer-Polymorphic set of neutral set of carbohydrates present on both RBCs and mucosal epithelium Methods for direct detection of viruses - Correct Answer--Electron microscopy -Immunofluorescence -ELISA -PCR The least specific method of direct viral detection is ______. - Correct Answer- electron microscopy Indirect detection of viruses can be done by culturing viruses in __________. - Correct Answer--Laboratory animals -Embryonated eggs -Cell culture _________ is an example of a virus that causes rounding in host cells. - Correct Answer-Vaccinia virus ________ is an example of a virus that causes cell lysis. - Correct Answer- Measles ________ is an example of a virus that causes syncytia. - Correct Answer- Measles GMS 6121 Exam 1 With 100% Correct And Verified Answers 2024 ________ is an example of a virus that causes inclusion bodies. - Correct Answer-Rabies virus ____________ is used for detection of influenza virus. - Correct Answer- Hemadsorption ________ can be used to detect presence of Maloney murine sarcoma virus. - Correct Answer-Transformation Endpoint titration - Correct Answer-Multiple replicate wells of cells are infected with 1 ml of each of several different dilutions, incubated, and scored for infection by looking for CPE. Hemagluttination - Correct Answer-viral particles serve to bind together RBCs Multiplicity of infection (MOI) - Correct Answer-the number of infectious particles per cell Influenza A viruses are identified based on their ____________. - Correct Answer-surface proteins Papillomaviruses encode an _________ that blocks a cellular _______ gene. - Correct Answer-oncogene; tumor suppressor Hemagluttinin binds to ________. - Correct Answer-sialic acid Influenza virus replicates in the ___________. - Correct Answer-nucleus ____________ cleaves sialic acid. - Correct Answer-Neuraminidase _________ genes are difficult to study, because you cannot generate a virus stock. - Correct Answer-Essential The most significant reason for the higher rate of spontaneous mutation in RNA viruses is... - Correct Answer-poor fidelity of the polymerase DNA viruses are more ________, while RNA viruses are more _______. - Correct Answer-stable; adaptable The most common means of inducing mutations in viral genomes is ___________. - Correct Answer-UV crosslinking Picornaviruses have ______-sense RNA genomes. - Correct Answer-positive _____________ is an oncolytic virus, meaning it causes lysis of tumor cells. - Correct Answer-Senecavirus VPg is covalently attached to the ____________. - Correct Answer-5' terminal nucleotide The function of the VPg protein is to protect the _______ from ______. - Correct Answer-5' end of the genome; exonucleases Examples of enteric virus groups - Correct Answer--cardioviruses -enteroviruses -hepatoviruses -parechoviruses Rhinoviruses and apthoviruses replicate in the ___________. - Correct Answer- respiratory tract