Biology Test
Life cycle of SARS-CoV-2
1. A surface s protein identifies and ACE-2 receptor on an epithelial cell (attachment and entry) 2. The virus translates a few peptides and assembles RNA polymerase. 3. The viral genes are converted to mRNA. 4. mRNA is translated into proteins. (2-4 uncoating, translation and transcription) 5. Three of the structural proteins are sent to the rough ER and Golgi apparatus, and the fourth is used to assemble the nucleocapsid. (assembly) 6. New viruses are packaged in lysosomes before they leave the host cell. (release)
Arrange the steps used to create a COVID-19 vaccine using mRNA for the SARS-CoV-2 S protein.
1. Identify a protein specific to SARS-CoV-2 2. Create an artificial mRNA sequence for the protein 3. Synthesize a lipid vector for transportation
Place the steps in order, starting at the top, to summarize how SARS-CoV-2 causes COVID-19.
1. Infected aerosols or small droplets of fluids enter the nose or mouth 2. The virus travels to the lungs, reaching the alveoli. 3. The virus targets epithelial cells lining the lungs. 4. The viral spike proteins recognize the ACE-2 receptors on host cells. 5. The regulation of angiotensin, and thus blood flow to the alveoli, is dysregulated. Blood flow to the alveoli, is dysregulated. 6. Symptoms like loss of taste and smell, cough, and tiredness develop.
Which of these is part of the challenge associated with predicting how a virus will move between individuals and populations?
1. some viruses mutate quickly 2. different viruses are transmitted differently 3. a virus might be asymptomatic and spread before it can be well-controlled
Approximately how many genes make up the genome of SARS-CoV-2?
20
Coronaviruses that are relatively harmless to humans
229E, NL63, OC43, and KHU1
What percentage of all diseases in humans originated in animals other than humans?
60%
Genetic analysis of coronavirus strains in pangolins, when compared to SARS-CoV-2, showed
90%
Genetic analysis of coronavirus strains in horseshoe bats, when compared to SARS-CoV-2, showed
96%
Select the explanation for one of the processes by which coronaviruses virus evolve.
A mutation that changes the viral spikes is introduced into the genetic material.
Which of these host cell structures is compatible with the S protein of SARS-CoV-2, allowing for the identification of target epithelial cells?
ACE-2
Outbreak
Disease moves from one population to another
Animals proposed as SARS-CoV-2 hosts
Horseshoe bats, pangolins, minks, snakes
Select the descriptions of the current state of COVID-19 vaccine development.
New vaccines are being designed to work around issues with S protein mutations. New vaccines are being designed with proteins that don't change as fast and that are similar between coronaviruses. New vaccines are being designed to address issues with SARS-CoV-2 evolution, which is a slow process. New vaccines are being designed with nucleocapsid proteins.
Which of these describes a unique aspect of SARS-CoV-2 replication?
Newly synthesized viruses are packaged in lysosomes.
An activated B cell that produces large amounts of antibody specific to a detected antigen is called a
Plasma Cell
Features present in basic structure of virus
Protein capsid and nucleic acid core
Genetic material of a coronavirus
RNA with helical nucleocapsid
Antigenic drift
Results in a change to the surface spikes of the virus, Can be attributed to RNA polymerase inefficiency, May make vaccines less effective and cause local outbreaks
Which of these is the best explanation of the process by which S protein from the SARS-CoV-2 virus is used to manufacture a COVID-19 vaccine?
S protein mRNA is manufactured using the viral genetic sequence and then enclosed in a lipid coating that serves as a vector to deliver the mRNA in an injectable vaccine.
While some SARS-CoV-2 vaccines are made with killed virus, others are built using __________ proteins as antigens
S; Spike
Coronaviruses dangerous to humans
SARS-CoV, MERS-CoV, SARS-CoV-2
homologous structures
Structures in different species that are similar because of common ancestry.
Pandemic
The disease spreads to globally distant populations
What is a Capsid?
The protein coat of a virus
How are scientists working around the challenges to the development of a universal COVID-19 vaccine?
They are working on designing vaccines using viral proteins that do not evolve as quickly as the S protein.
Which of these describes the cytokine storm that occurs in some individuals during a COVID-19 infection?
This phenomenon is relatively rare. The immune system produces a large number of proteins associated with regulating inflammation.
Antigenic shift
Typically involves animal hosts, Delays immune response and may cause an outbreak, A host cell manufactures particles from two forms of the virus
Which of these statements explains the general process of how viruses reproduce?
Viruses use the machinery of their host cell to make copies of themselves. (LYTIC and LYSOGENIC cycle)
Examples of emerging diseases
West Nile virus, H1N1, Yellow fever, Entero virus, SARS, MERS, Ebola, Diphtheria, Avian influenza H7N9
Select all the possible consequences of antigenic shift in the SARS-CoV-2 virus.
a new combination of spikes on the surface of the virus, slow adaptation by the immune system, global outbreak
What is a lysosome?
an organelle with an acidic pH that typically breaks down organic molecules
Select common methods for treating the symptoms of COVID-19.
antiviral medications over-the-counter medications steroids rest
Select the methods currently being used across the world to treat COVID-19 infection.
antiviral medications steroids monoclonal antibodies
Animals linked to coronaviruses in china 2002-2003
bats and civet cats
Common animal hosts for coronaviruses
bats, camels, birds, livestock, and humans
A virus targets a host cell using its
capsid proteins
What does the peptide hormone angiotensin do?
controls blood pressure
Within the genome of SARS-CoV-2,
each of the membrane proteins and the nucleocapsid are encoded separately by four specific genes.
E proteins
envelope proteins involved in viral assembly and exit from host
Which stage of disease movement in the development of the COVID-19 global pandemic was the beginning, and is associated with a single country?
epidemic
What evidence is used to determine the most likely animal origin of SARS-CoV-2?
genetic analyses
Like other RNA viruses, coronaviruses have ______ mutation rates.
high
Select the descriptions of ACE-2 receptors.
involved in the regulation of a peptide hormone stands for angiotensin-converting enzyme 2 connected to the regulation of blood flow and gas exchange in the lungs found on the surface of epithelial cells
Coronaviruses are ______ other single-stranded viruses.
larger than
Which of these are descriptions of antibody testing for COVID-19?
looks indirectly for antibodies made in response to exposure can also be called a rapid test indicates a previous exposure to the virus
In which viral life cycle is viral DNA replicated along with the host cell DNA, creating new cells that contain the virus?
lysogenic
M Proteins
membrane proteins involved in viral assembly
The helical protein structure that surrounds the RNA of a coronavirus is called a(n)
nucleocapsid
Epidemic
number of infected individuals exceeds previous years
If you were asked to summarize the general methods of prevention, detection, and treatment of COVID-19, which of these would you include?
practicing social distancing rest, hydrate, and wait for the virus to run its course washing hands regularly with soap and water vaccination taking rapid tests
analogous structures
serve the same function, may appear the same, but evolved independently to specific environment(wings of bats, birds, insects)
Select the ingredients you'd expect to find in a typical COVID-19 vaccine.
sodium acetate acetic acid lipids S protein mRNA
S Proteins
spike proteins; responsible for attachment to specific receptors in host cells
What is the focus of vaccine research in terms of their design?
the S protein on the viral capsid
The antiviral medications used to fight COVID-19 are able to specifically target the virus by targeting
the enzyme that removes the genetic material from the viral capsid. molecules on the surface of host cells to prevent attachment. the enzyme that interacts with the host membrane molecules to allow the escape from the host cell.
Viruses that evolve in animal hosts have the potential to produce severe illness in humans because
the human immune system has never experienced the unique characteristics of these viruses.
Common COVID-19 symptoms
trouble breathing loss of smell skin rash runny nose
Vaccines contain a piece of a _________ , that can be shown to the human host so they can arm their immune response against future exposures.
virus