A positive-strand RNA virus: a. must first be converted to a mRNA before viralproteins can be translated b. is not recognized by host ribosomes. c. can directly translate viral proteins. d. will be degraded by host enzymes. e. needs RNA dependent RNA polymerase to get converted into mRNA

Viruses are made up of the same biomolecules as cellular organisms (DNA, RNA, proteins, lipids, etc.), which are synthesized through enzymatic dehydration reactions from building blocks and disassembled by enzymatic hydrolysis. They infect cells and replicate themselves using resources from the host cells. Scientists discovered a previously unknown strain of virus in the tropical Pacific Ocean and it can infect higher-order eukaryotes. Initial analysis revealed that the virus is mainly composed of nucleic acids, proteins, and lipids. Chemical analysis after complete hydrolysis revealed the following building blocks (by weight): Chemical components Nucleosides Amino acids Lipids, phosphates, and carbohydrates Percentage by weight 20 30 50 Analysis of percentages of nucleosides yielded the following results (by molar ratio): Nucleosides A G T C U Percentage by mole 19 29 19 29 4 Which of the following events mostly involves hydrolysis reaction after the virus infects…

Which class of RNA is correctly paired with its function? a. Small nuclear RNA (snRNA): processes rRNA b. Transfer RNA (tRNA): attaches to an amino acid c. MicroRNA (miRNA): carries information for the amino acid sequence of a protein d. Ribosomal RNA (rRNA): carries out RNA interference

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A. DNA viruses generally cause malignancy by : inserting themselves in the host DNA, possible because their genome is similar to that of the host activating a cellular growth factor receptor, that activates the signal transduction pathway. inactivating a tumor suppressor gene, that results in uncontrolled proliferation. B. PDGF is overexpressed in certain cancers. This is an example of a mutation in the --- region a. regulatory b. coding

You would like to create an anti-viral medication that is active against both H5N2 and H5N1 strains of influenza. The best drug target would be: a. ribosomal protein production b. Hemagglutinin-mediated fusion c. Neuroaminidase-mediated budding

Rabies is a viral zoonosis that is transmitted directly from the bite of an infected animal. The rabies vaccine is prepared by treating virus with a chemical that renders it unable to infect and replicate. What type of vaccine is this? a. whole cell b. attenuated c. subunit  d. inactivated

Notice the comment that after treatment your CD4 count should rise. Why does treatment allow CD4s to increase?   A Anti-retroviral therapy consists of transfusions of CD4 cells.   B Anti-retroviral therapy directly stimulates cell division of CD4 cells, so their numbers increase.   C Anti-retroviral therapy will prevent HIV from replicating and killing your CD4s. CD4s can grow back to some degree.

RNA viruses require their own supply of certain enzymes because Select one: OA. these enzymes penetrate host cell membranes. O B. these enzymes cannot be made in host cells. С. host cells lack enzymes that can replicate the viral genome. D. these enzymes translate viral mRNA into proteins. E. host cells rapidly destroy the viruses.

Two component systems in E. coli often refer to: Select one: an activator and a repressor for gene transcription O a. O b. a specific mRNA and an anti-sense small RNA. O c. a toxin and an anti-toxin O d. a kinase and its substrate protein