Viruses – Microbiology Test Questions – Flashcards
Unlock all answers in this set
Unlock answersquestion
| Are viruses capable of living without a host? Why? |
answer
| NO. Lack metabolism |
question
| What do they contain that makes them able to live once they infect a host? |
answer
| All the info necesarry to direct metabolic processes (DNA/RNA) |
question
| What are viruses classified as? |
answer
| Infectious particles |
question
| What are target cells? |
answer
| Viruses interact and infect specific cells |
question
| Are there cells in the body that are not succeptible to viruses? |
answer
| No |
question
| _____ _____ infected by a reproducing virus will ultimately die. |
answer
| Most cells |
question
| What are the common symptoms of viral infections? |
answer
| Rash, fever, muscle aches, respiratory involvement and swollen lymph nodes. |
question
| What are oncoviruses? |
answer
| Viruses linked to cancer |
question
| What are zoonotic viruses? |
answer
| Viruses carried by animals. |
question
| Many viruses take up _______ _______ in the host and alternate between ______ and ______ stages. |
answer
| permenant residence/active/latent |
question
| Are infants of infected mother's succeptible to viruses before or after birth or both? |
answer
| BOTH. Viruses can cross the placenta. RUBELLA CAN KILL FETUS> |
question
| What is the general structure of a virus? |
answer
| RNA or DNA with a protein coat |
question
| What is the size of a virus? |
answer
| ultramicroscopic |
question
| How many viruses could fit into an average bacterial cell? |
answer
| 2,000 |
question
| What is a capsid? Is it on all viruses? |
answer
| The outer shell of a virus. YES. |
question
| What is the capsid made of? |
answer
| Repeating structures known as capsomeres. |
question
| What are capsomeres composed of? |
answer
| Small clusters of proteins. |
question
| What are the three common shapes of viruses? |
answer
| 1.)Helical 2.)Polyhedral 3.)Complex |
question
| What are helical viruses? |
answer
| Composed of rod shaped capsomeres arranged into hollow disks. TOBACCO MOSAIC VIRUS. |
question
| What are polyhedral viruses? |
answer
| Capsomeres arranged into equilateral triangles that fit together to form a spherical structure. ADENOVIRUS & CORONAVIRUS |
question
| What are complex viruses? |
answer
| Have polyhedral head, helical tail and attachment fibers. ONLY IN BACTERIOPHAGE. |
question
| How many viruses have viral envelopes? |
answer
| Most |
question
| What does the viral envelope surround? |
answer
| The capsid |
question
| What is the viral envelope created from? |
answer
| Portions of the host cell's membrane |
question
| What is the viral envelope composed of? |
answer
| Lipids and proteins |
question
| A "naked virus" is one that does not have a... |
answer
| viral envelope. |
question
| Is a naked cell more durable than a non-naked? |
answer
| yes |
question
| What are the host cell's membrane replaced with? |
answer
| Portions of viral proteins |
question
| What connects the envelope to the capsid? |
answer
| Viral proteins |
question
| What are viral spikes? |
answer
| Viral proteins that protrude from the surface of a protein |
question
| What do viral spikes aid in? |
answer
| The attachment of the virus to a NEW host cell |
question
| What are the three functions of the capsid/envelope? |
answer
| 1.)Protects the virus from enzymes 2.)Helps facilitate movement of viral DNA/RNA into host cell 3.)Attachment |
question
| Are nucleic acids found in all viruses? |
answer
| YES |
question
| Is it DNA, RNA, or both? |
answer
| One or the other, CANNOT BE BOTH |
question
| DNA can be _____-stranded or single-stranded or ______ or ______. |
answer
| double/circular/linear |
question
| Is human viruses circular or linear? |
answer
| Linear. So Circular are bacterial. |
question
| RNA is always ______ & ______-______. Rare cases of ______-______. |
answer
| Linear/double-stranded. Single-stranded |
question
| What do nucleic acids do once they invade a host cell? |
answer
| Direct the actions of the host cell. |
question
| What are viruses sometimes called? |
answer
| Genetic parasites |
question
| What are 3 enzymes carried by viruses? |
answer
| DNA/RNA polymerase, digestive enzymes, endonucleases |
question
| What does DNA/RNA polymerase do? |
answer
| Direct the duplication of DNA/RNA in the host. |
question
| What do digestive enzymes do? |
answer
| Digest the host cell's DNA, RNA and/or proteins |
question
| What do Endonucleases do? |
answer
| Cut host cells DNA to allow insertion of viral DNA. |
question
| What are the two models of viral multiplication? |
answer
| 1.)Bacteriophage 2.)Animal Virus Model |
question
| What are the steps for Bacteriophage Multiplaction? |
answer
| 1.)Adsorption 2.)Penetration 3.)Replication 4.)Assembly 5.)Release |
question
| What happens during the adsorption phase? |
answer
| The coming together of the virus and host cell. Occurs on the cell wall, pili or flagella. |
question
| What happens during the penetration phase? |
answer
| The phage pushes an inner tube through the cell wall and injects its nucleic acid into the host. |
question
| Does the entire virus enter during this step> |
answer
| No. |
question
| What happens during the replication phase? |
answer
| The viral nucleic acid starts shutting down the host cell's metabolism and then directs the host's machinery to produce new viral components |
question
| What happens during the assembly phase? |
answer
| The viral components spontaneously assemble into new bacteriophages. |
question
| What happens during the release phase? |
answer
| The host cell explodes releasing the viruses. |
question
| What are the 5 steps of the Animal Virus Model? |
answer
| 1.)Adsorption 2.)Penetration 3.)Uncoating 4.)Replication & Assembly 5.)Release |
question
| What is the only 2 differences between the AVM and the Bacteriophage model? |
answer
| In AVM, Penetration = THE ENTIRE VIRUS Release = BUDDING/EXOCYTOSIS NO LYSES |
question
| How are viruses classified further? |
answer
| By routes of transmission |
question
| What are enteric viruses? |
answer
| Fecal-oral route |
question
| What are respiratory viruses? |
answer
| Inhaled with droplets then multiply within respiratory tract. |
question
| What are zoonotic viruses? |
answer
| Animal to human transmission |
question
| What are Sexually Transmitted viruses? |
answer
| Sexually transmitted. |
question
| How are families and genera named? |
answer
| fam - viridae gen - virus |
question
| What are the 5 types of DNA viruses that infect vertebrates? |
answer
| 1.)Adenoviridae 2.)Poxviridae 3.)Herpesviridae 4.)Papillomaviridae 5.)Hepandnaviridae |
question
| What does the adenoviridae cause? |
answer
| Common cold - adenovirus |
question
| What does the poxviridae cause? |
answer
| Smallpox & cowpox |
question
| What 4 viruses are apart of the Herpesviridae family? |
answer
| 1.)Herpes Simplex I - coldsores 2.)Herpes Simplex 2 - genital warts 3.)Varcinella-Zoster Virus - chickenpox and shingles. 4.)Epstein-Barr Virus - Mono |
question
| What family is Human papillomavirus apart of and what does it cause? |
answer
| Papillomaviridae. warts. |
question
| What family is hepatitis b apart of and what organ does it affect? |
answer
| Hepadnaviridae. Liver. |
question
| What are the 11 families of RNA viruses infecting vertebrates? |
answer
| 1. Piconaviridae 2. Orthomyxoviridae 3. Paramyxoviridae 4. Togaviridae 5. Rhabdoviridae 6. Filovivirdae 7. Bunyaviridae 8. Retroviridae 9. Coronavirdae 10. Calciviridae 11. Flaviviridae |
question
| What family does Poliovirus, Rhinoviruses, and Hepatitis A Virus belong to and what do they cause? |
answer
| Piconaviridae. polio, common cold, least severe hepatitis. |
question
| What does the orthomyxoviridae family cause? |
answer
| Influenza A B C |
question
| What does the paramyxoviridae family cause? |
answer
| Paramyxovirus - mumps Rubeola - Measels |
question
| What does the Togaviridae family cause? |
answer
| Rubella virus (Rubella = german measels) |
question
| What does the Rhabdoviridae family cause? |
answer
| Rhabdovirus aka rabies |
question
| What does the Filovivirdae family cause? |
answer
| Ebola and Marburg viruses |
question
| What does Bunyaviridae family cause? |
answer
| Hantavirus |
question
| What does Retroviridae family cause? |
answer
| HIV and AIDS |
question
| What does Coronaviridae cause? |
answer
| Common cold, SARS |
question
| What does Calciviridae cause? |
answer
| Norovirus (Norwalk virus) |
question
| What does Flaviviridae cause? |
answer
| Heptatis C and Yellow fever. |
question
| What are 5 ways of detecting viral infections? |
answer
| 1.)Examination of symptoms 2.)Detection of cytopathic changes 3.)Detection of viral DNA/RNA in host cells 4.)Isolation and culturing 5.)Detection of antibodies created in reaction to a virus |
question
| What do you look for when searching for cytopathic changes? |
answer
| 1.)Virus induced damage to the cell a.)Inclusion bodies I.)Compacted masses of new viruses or damaged cell organelles. |
question
| When treating a viral infection, do you treat the infection or symptoms? |
answer
| Symptoms. |
question
| Are antibiotics effective against viral infections? |
answer
| No. |
question
| What do antiviral drugs aim to block? Do they cause adverse side effects? |
answer
| Viral replication by disrupting host cell structure/function. Yes. |
question
| What is an interferon? |
answer
| A body's natural defense against viruses |
question
| What is an interferon produced by? What does it protect? |
answer
| A virus-infected cell. Neighboring cells. |
question
| What are the 6 ways antiviral drugs work? |
answer
| 1.)Inhibit viral penetration/uncoating 2.)Inhibit neuraminidase 3.)Inhibit viral DNA polymerase 4.)Inhibit viral reverse transcriptase 5.)Inhibit viral protein synthesis 6.)Inhibit viral RNA polymerase |
question
| Amantadine inhibits... |
answer
| viral penetration/uncoating |
question
| Oseltamivir inhibits... |
answer
| Neuraminidase |
question
| Acyclovir or Valcyclovir inhibits... |
answer
| viral DNA polymerase |
question
| Zidovudine inhibits... |
answer
| Reverse transcriptase |
question
| Interferons inhibit... |
answer
| protein synthesis |
question
| Ribavirin inhibit... |
answer
| RNA polymerase. |
question
| What are Prions? |
answer
| A group of proteinaceous infectious agents that have been linked to a number of slow-progressing, fatal diseases of the CNS in humans and animals. |
question
| All diseases result in... |
answer
| brain function degeneration. |
question
| What are prion diseases known as? |
answer
| Transmissible spongiform encephalopathies |
question
| What do prion diseases result from? |
answer
| The death of neurons and formation of spongelike holes in the brain. |
question
| What is a prion composed of? |
answer
| ONLY PROTEIN. NO NUCLEIC ACID. |
question
| Prions _____ not _____. |
answer
| activate/replicate. |
question
| We have prions in our brains as a protein already. T or F |
answer
| T |
question
| How is the prion protein acquired? |
answer
| Injesting infected CNS cells (meat products) |
question
| Once infected, what does a prion cause? |
answer
| A mutation of the normal protein's tertiary structure which fucks up function. |
question
| What is scrapie? |
answer
| Sheep prion disease |
question
| what is Kuru? |
answer
| Human prion disease |
question
| What is Creutzfeldt Jakob disease? |
answer
| Mad cow in humans |
question
| What is Mad Cow Disease/BSE? |
answer
| Cattle prion disease |
question
| What is chronic wasting disease? |
answer
| Deer, elk and moose. |
question
| What are prions destroyed by? |
answer
| Chemicals that denature proteins and heat so it is possible to cook it out of meat products. |
question
| what are viroids? |
answer
| Consists of a single stranded circular RNA molecule with NO PROTEIN COAT |
question
| What do viroids infect? |
answer
| PLants |
