MMBB 154 – Microbiology – Flashcards
Unlock all answers in this set
Unlock answersWhat two components do all Virus' have? |
Nucleic Acid (RNA or DNA) Protein |
What is the phospholipid bilayer of protein that covers some viruses called? |
Envelope |
What is a virion? |
Virus completely assembled outside the host cell |
What is a bacteriophage? |
Virus that infects bacteria |
What is a retrovirus? |
An RNA virus that uses reverse transcripts to synthesize DNA using RNA as a template |
What is the average size of a virus? |
20 - 250 nanometers |
What was Ivan Iwanowski famous for? |
|
What is the replication process of bacteriophages? |
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What is the Virus genome? |
Nucleic Acid
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What is the purpose of the virus capsid? |
surrounds genome with a coat of protein
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What is a capsomere? |
Individual protein subunits of the capsid |
What is the Nucleocapsid? |
Genome and the capsid |
What happens during the attachment step in Replicating bacteriophage? |
Sites on phages tail fibers match with a complementary receptor site on the cell wall of bacterium |
What happens during the Penetration step in Replicating bacteriophage? |
The tail of the phage releases the enzyme lysozyme to dissolve a portion of the bacterial wall. Drives through cell wall |
What happens during the Biosynthesis step in Replicating bacteriophage? |
Phage DNA uses bacterial nucleotides and cell enzymes to synthesize multiple copies of itself |
What happens during the Maturation step in Replicating bacteriophage? |
Replicated bacteriophage DNAs and the capsids are assembled into complete virons |
What happens during the Release step in Replicating bacteriophage? |
Phages are released |
What are the different shapes of Virus? |
Helix Icosohedron Complex |
What are the methods to visualizing virus's? |
Electron Microscope Cytology uses light microscopy to examine cells for cytopathic effects (CPEs) of viral infection |
What is an example of a helical shaped virus? |
Rabies, Tobacco Mosaic (tightly wound coil resembling a corkscrew or spring) |
What is an example of a icosahedral shaped virus? |
herpesvirus, poliovirus (head with a collar and tail) |
What is an example of a complex shaped virus? |
smallpox (brick shaped) |
What is a viroid? and give an example. |
Tiny fragments of nucliec acid known to cause diseases in crop plants
Ex. Potato spindle tuber disease
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What did Theodore O. Diener discover would kill Potato Spindle Tuber (PST)? |
an RNA degrading enzyme |
What is a prion? ... protein only hypothesis |
Proteinaceous infectious particles, meaning that prions are composed solely of PROTEIN and contain NO nucleic acid |
What are the two types of prion proteins? |
PrPc = normal protein PcPsc = abnormally shaped protein |
where are normal proteins found? |
surfaces of the brain |
What are the suspected infectious agents of diseases like mad cow and scrapie? |
PcPsc : abnormally shaped protein |
Small, obligate intracellular particles composed of nucleic acid as either DNA or RNA and in either a single stranded or double-stranded form? |
Virus |
The genome is surrounded by a protein _____, and many viruses have an ______ surrounding the nucleocapsid. |
Capsid Envelope |
What are used as attachment to host cells? |
Spikes |
How do prions cause disease? |
By folding improperly and in the misfolded shape, cause other prions to misfold |
Mad Cow Disease, variant Creutzfeldt-Jacob disease (vCJD), Scrapie and Wasting disease in elk and deer are all examples of what broader class? |
transmissable spongiform encephalopathies (TSEs) |
lack proteins and a capsid, but can replicate themselves inside the host |
viroids |
Upper Respiratory tract disease, very contagious, transmitted by inhalation of droplets |
Influenza |
Antigenic variation? |
the process in which Hemagglutinin (H) and Neuraminidase (N), where they change the sequence of amino acids that make-up the protein molecules |
What is the purpose of H & N? |
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What aberrant immune response is linked to the use of aspirin in children? |
Reyes Syndrome |
31 types of isosahedral virions, ds DNA, swollen lymph nodes? |
Adenovirus of the Common Cold |
Viral infections of the URT? |
Common colds: rhinovirus, adenvirus laryngitis: rhinovirus |
Viral infections of the LRT? |
Influenza: A & B Respiratory syncytial (RS) disease: Respiratory syncytial virus Parainfluenza: Human parainfluenza virus 1 & 3 SARS : Sars coronavirus Hantavirus pulmonary syndrome (HPS): Hantavirus |
Disease of the Skin caused by herpesviruses? |
Cold Sores: Herpes simplex 1 Chickenpox and Shingles: varicella zoster
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Other viral disease of the skin? |
Measles: Measles virus Mumps: paramyxoviruses Rubella: Rubella virus Smallpox: Variola |
Newly emerging viral disease and transmitted by close person to person contact and fomites |
Severe acute respiratory syndrome (SARS) |
Incubation period of 2 weeks, transmitted by inhalation of respiratory droplets or skin contact, highly contagious
ds DNA virus, icosahedral symmetry, enveloped with spikes |
Varicella zoster (chickenpox) |
Re-activation of latent virus and occurs in about 10% of elderly adults? |
Shingles (Zoster) |
Very contagious, spread by inhalation of respiratory
RNA, helical shape, enveloped, spikes of hemagglutinin |
Measles (Rubeola) |
Red Rash.... what is maculopapular? |
starts on face/head spreads to extremities |
What is the vaccine for Shingles (Zoster)? |
Zostavax - vaccine with attenuated virus |
Why is German measles (Rubella) dangerous in pregnant women? |
virus can cross placenta in the first trimester of pregnancy |
What are the symptoms of Rubella? |
+/- fever pale pink maculopapular rash swollen lymph nodes mild cold symptoms |
RNA helical virion, enveloped, spikes of hemagglutinin and neuraminidase?
But only effects salivary glands...Parotid Gland!! |
Mumps |
Where is the mumps virus found? |
blood urine CSF |
very rare tumor of blood vessel tissue associated with aging? |
Kaposi's sarcoma |