COVID-19

What is the median incubation period for CO-VID19? 7-9 days 5-6 days 2-4 days 11-13 days

5-6 days

S, E, M, and N are four structural proteins that are encoded by the subgenomic RNAs of the COVID-19 virus. True False

True

The first viral protein that is expressed in the infected cell is actually a series of multiple proteins translated together as a polyprotein. The polyprotein is cleaved into functional proteins by a viral-encoded protease. Question: How many proteins are derived from the original polyprotein? 16 56 25 5

16

Which two proteins encoded by SAR-COV-2 are translated from the positive strand RNA and are involved in adding or modifying the CAP on viral RNAs? nsp11 and nsp12 nsp13 and nsp15 nsp6 and nsp7 M and N proteins

nsp13 and nsp15

Which of the following is not encoded in the viral RNA? Protein shell coating the RNA Protein spikes Envelope of the viral particle All of the following are the main components

Envelope of the viral particle

Which protein protects the viral RNA, keeping it stable inside the virus? Signal Blocker Membrane Protein (M) Nucleocapsid Protein (N) Envelope Protein (E)

Nucleocapsid Protein (N)

The _____ protein(s) binds the 40S ribosome of the host and cleaves the 5'-end of host mRNAs, which removes the CAP and results in their degradation. It does not cut the viral RNAs because the virus has methylated the CAP of its own RNAs to mark them as viral. nsp11 nsp3 nsp1 nsp3

nsp1

In the genomic map below of SAR-COV-2, which proteins are translated from the original positive-strand RNA that is packaged in the viral particle? structural proteins for ORFs 1, 3, 11, and 15 S, E, M, and N nsp1-16 nsp 20-27

nsp1-16

The RNA dependent RNA polymerase and viral helicase are encoded by which of the following nonstructural proteins (nsp's)? nsp11 and nsp 12 nsp6 and nsp12 nsp1 and nsp1 nsp13 and nsp15 PreviousNext

nsp11 and nsp 12

Label the numbers in the image showing the binding of the SARS-CoV particle to a lung cell. 1 2 3 4 -spike protein of spike -ACE2 receptor on the outer surface of th human cell -stem portion of spike protein (S2) -human protease that cuts at two sites within the spike protein to release the head portion (S1) and activate unfolding of the stem

1 spike portion of spike protein S1 2 ACE2 receptor on the outer surface of the human cell 3 stem portion of spike protein (S2) 4 human protease that cuts at two sites within the spike protein to release the head portion (S1) and activate unfolding of the stem

What are two reasons that SARS-CoV uses subgenomic RNAs? 1-This increases the production of interferon by the host cell, and 2-permits mismatch repair of the error-prone transcripts. 1-This helps evade the host immune system, and 2-triggers epigenetic silencing of host genes. 1-This enables each of the coding regions to be translated, and 2-RNA recombination resulting from the "Jump and Copy" mechanism of the RdRP facilitates error correction by RNA recombination. 1-This helps amplify the amount of mRNA for viral proteins, and 2-permits Non-homologous End Joining to assist in replication

1-This enables each of the coding regions to be translated, and 2-RNA recombination resulting from the "Jump and Copy" mechanism of the RdRP facilitates error correction by RNA recombination.

SARS-C0V Spike protein: Label the parts of the spike protein. 1 2 3 4 5 6 7 8 -ACE2 Bind Domain -Glycan sugar moietes that decorate the spike protein to hide it from immune system -cut side 2 (activates the stem to unfold) -cit side 1 (releases the spike s1 domain) -stem -released by cut 2 resulting in activation of the stem to unfold -fusion domain exposed by cut 2 (embeds into host cell membrane) -transmembrane domain that is embedded in viral envelop

1-transmembrane domain that is embedded in viral envelop 2-cit side 1 (releases the spike s1 domain) 3-cut side 2 (activates the stem to unfold) 4-Glycan sugar moietes that decorate the spike protein to hide it from immune system 5-ACE2 receptor binding domain of the spike 6- steam region, which in this image is folded on itself 7- region that is released by cut 2 8 fusion domain that becomes embedded into the host membrane when the stem unfolds

How long does COVID-19 live on polypropylene plastic? 3 days 4 hours 2 days 12 hours

3 days

Which viral protein serves a proofreading function that protects the large genome of SARS-CoV from excessive mutations? (This protein has two activities. Its other function is to add a 5'-Cap to newly synthesized viral RNAs.) E protein ExoN (nsp 13) M protein spike

ExoN (nsp 13)

The only known tissue where the SARS-CoV-2 virus can replicate is in lung epithelial cells. True False

False

True or False: One commonality between COVID-19 and a flu virus is that both of them must enter the nucleus to take control of the cell. true False

False

What is the most common symptom of COVID-19? Diarrhea Fever shortness of breath Dry cough

Fever

How does COVID-19 actually kill you? It attacks the kidney cells causing the to not be able to filter out toxins from the blood. It causes a very robust immune response throughout the lungs that causes inflammation of the alveoli. This inhibits gas exchange and causes the alveoli to fill with fluid. It attacks the reproductive organs causing severe pain and inflammation. It stress the heart by constricting thousands of capillaries in the lungs.

It causes a very robust immune response throughout the lungs that causes inflammation of the alveoli. This inhibits gas exchange and causes the alveoli to fill with fluid.

In order to get rid of the virus on your skin, why is soap important? Soap is able to penetrate the nucleocapsid proteins that protect the RNA in the core of the viral particle. Soap is inhibitory to viral replication. It dissolves the lipid membrane envelope of the virus. It inactivates the RNA.

It dissolves the lipid membrane envelope of the virus.

During replication of the virus, which structural protein encoded by the virus embeds itself into the host membranes of the ER and Golgi complex and causes a region to bleb out to form the envelop of the viral particle? RNA dependent RNA polymerase (RdRp) anti-silencing protein Membrane (M) and Spike (S) proteins Nucleocapsid Protein

Membrane (M) and Spike (S) proteins

Which SARS-CoV protein has homology to the palm, thumb, and fingers domains of DNA polymerase? reverse transcriptase nsp 7/8 complex (primase) ExoN RNA dependent RNA polymerase (RdRP)

RNA dependent RNA polymerase (RdRP)

The _______ protein attaches to the host ACE2 receptor and then promotes fusion of the host membrane with the envelop of the viral particle. S nsp1 N M

S

What is the best evolutionary rational for having the nsp's translated first before the structural proteins? The proteins encoding the enzymatic activities are generally smaller than the structural proteins. There would not be enough room on the negative strand transcripts to include all 16 proteins. The nsp's encode enzymatic activities that prepare the way for replication processes which is an early step in the cycle. It makes sense that these proteins are synthesized first, because they are needed prior to assembly of the viral particle. There is probably not evolutionary advantage. The assignment was initially random, and then was conserved.

The nsp's encode enzymatic activities that prepare the way for replication processes which is an early step in the cycle. It makes sense that these proteins are synthesized first, because they are needed prior to assembly of the viral particle.

What is the main function of the protein spikes? The spikes have affinity for the ACE2 protein found in the membrane of the host lung epithelial cells. The spikes allow the viral particle to initially attach to the host membrane and then promote the fusion of the viral envelope with the host cellular membrane. To ward off pathogens (poke them in the eye) To store nutrients for the virus (Yum...nothing like a good spike soup.) To kill cells (Die, die, die, I say!)

The spikes have affinity for the ACE2 protein found in the membrane of the host lung epithelial cells. The spikes allow the viral particle to initially attach to the host membrane and then promote the fusion of the viral envelope with the host cellular membrane.

The function of the nsp1 protein is slow down expression of host mRNAs so that viral RNAs are favored. It does this by binding to the 40S ribosome and then cutting the CAP off the host mRNAs as they arrive for translation. True False

True

True/False The R-Naught (RO) value is not intrinsic to the virus, it depends on environmental conditions and the behavior of a culture or society. True False

True

True/False The RNA viruses like to attach to the ACE2 receptors in our cells, which are found in large amounts inside our lungs. True False

True

True/False The three S protein subunits form prominent "spikes" on the surface of the virus. One of the subunits has affinity for the ACE2 receptor, which is embedded in the membrane of host cells. These crownlike spikes give coronaviruses their name. True False

True

What is the origin of the membrane envelope of the viral particle? endoplasmic reticulum and the Golgi bodies of the host cell only the endoplasmic reticulum of the host cell the outer membrane of the host cell nuclear membrane of the host cell

endoplasmic reticulum and the Golgi bodies of the host cell

Which pair of nsp's form a primase to assist the RdRp? nsp7 and nsp8 nsp3 and nsp5 nsp1 and nsp3 nsp11 and nsp12

nsp7 and nsp8