Supplementary Lectures Flashcards
what is genomic drift
where the haemagglutinin of the virus changes slightly but is still recognisable
What are the steps of a haemagglutination inhibition assay
- Virus binds to RBCs 2. Specific antibodies prevent shield forming 3. Virus cannot cross link with RBC when antibody bound 4. RBC fall to the bottom of the well- button
What are the steps of a haemagglutination assay
- Virus binds to RBCs 2. Cells fall to the bottom of the wells due to gravity 3. Sialic acids bound to by virus, forming a shield at the well bottom 4. Perform serial dilution 5. The last well with a shield means you can calculate the virus titre
Explain the stages of viral replication
- virus adheres to cell surface 2. virus enters cell by pinocytosis 3. virus sheds coat 4. replication of viral nucleic acids 5. synthesis of viral protein of capsid 6. assembly of new virions 7. release of virus
What is a plaque assay
used to purify a clonal population of virus or to determine viral titer
What is the end-point of the assay
1/512
What is would a positive result of a haemagglutination inhibition assay show
button
What is the baltimore classification system
How viruses nucleic acids make mRNA
Would genomic drift or shift be more likely to cause a pandemic
Shift
What can viruses be classified based on
• Size, shape (helical, icosahedral, complex) • Type of nucleic acid in the genome (No strands/Sense) • How they produce mRNA
What strain of influenza is Patient ‘JB’ was infected by
H1 strain of influenza
What does neuraminidase facilitate
the release of the virus from infected host cells
What do viruses contain
• A Nucleic acid – RNA or DNA • Viral proteins on their surface • Nucleocapsid- forms shape • Lipid envelope- usually originates from host cell
True or false: Viruses are visible under a light microscope
False
Why can sense RNA viruses not act as an RNA template
risk of mutation
What is genomic shift
when the haemagglutinin of the virus changes completely
Explain the steps of a plaque assay
10-fold dilutions of a virus stock are prepared, and 0.1 ml aliquots are inoculated onto susceptible cell monolayers. Monolayers are covered with a nutrient medium containing agar original infected cells release viral progeny. each infectious particle produces a circular zone of infected cells called a plaque. Eventually the plaque becomes large enough to be visible to the naked eye.
How many groups are there in the baltimore classification system
7
What can be used to subtype viruses
neuraminidases
what is qt-PCR
the RNA in the virus is converted to CDNA which then gets amplified. It monitors the amplification in real-time
What does haemagglutinin facilitate?
entry of the virus into host cells (binds to sialic acid)
What is would a positive result of a haemagglutination assay show
a shield
