Question 1

Some viruses, like human papilloma virus (HPV) can cause cancer. How does HPV do this?

Accepted Answer

HPV can cause cancer by integrating its DNA into the host cell's genome, leading to the expression of viral proteins that can inactivate tumor suppressor proteins and stimulate re-entry into the cell cycle, promoting uncontrolled cell division.

Question 2

Why do viruses often seem to emerge from nowhere to become major public health scares in Canada?

Accepted Answer

Viruses are constantly evolving, and this can lead to them gaining the ability to infect new species, including humans, which can result in new public health challenges.

Question 3

Animal cells and viruses are in an ongoing 'arms race' to prevent and facilitate infection, respectively. Of the following evolved changes to the host, which do you think would be most effective at limiting viral infection?

Accepted Answer

Altering the structure of cell surface proteins that viruses use to recognize and bind to host cells would be most effective at preventing viral infection, as it would block the initial step of viral entry into the cell.

Question 4

The deadliest viruses for a population of people tend to be those which

Accepted Answer

A) Viruses that a population has never encountered before tend to be the deadliest because the population lacks immunity to these new pathogens, leading to more severe outbreaks and higher mortality rates.

Question 5

The genetic reshuffling of DNA from multiple viruses to create new and sometimes deadly viruses is an example of

Accepted Answer

The genetic reshuffling of DNA from multiple viruses to create new and sometimes deadly viruses is an example of horizontal gene transfer. This process allows for the exchange of genetic material between different viruses, leading to the emergence of new viral strains with potentially novel and more virulent characteristics. This is distinct from the accumulation of point mutations (C), survival of the fittest (B), or punctuated equilibrium (D), which are other concepts in evolutionary biology.

Question 6

In horizontal gene transfer a gene can be transferred between

Accepted Answer

Horizontal gene transfer involves the movement of genetic material between different organisms, not just between cells of the same organism or through traditional replication processes. A common example is the transfer of genes between a virus and its host genome, which can lead to significant genetic changes in the host.

Question 7

Rickettsia is a genus of bacteria causing serious infections in humans. Rickettsia reproduce inside of human cells, and they are dependent upon the host cell's machinery to do so. Like a virus, once replicated, Rickettsia are released from the host cell and can then go on to infect other cells. For Rickettsia to be considered a virus rather than a bacterium, what properties must it have?

Accepted Answer

Rickettsia, despite relying on host cell machinery for replication, is classified as a bacterium because it contains both RNA and DNA, and can carry out some of its own metabolic processes, unlike viruses that must fully rely on the host's cellular machinery for replication and do not have the capabilities for independent metabolism.

Question 8

The mitochondrial RNA polymerase of human cells is related to the T7 bacteriophage RNA polymerase. This appears, therefore, to be a case of

Accepted Answer

The similarity between the mitochondrial RNA polymerase of human cells and the T7 bacteriophage RNA polymerase is an example of horizontal gene transfer, a process where genetic material is transferred between unrelated species, rather than being passed down from parent to offspring. This can occur through various mechanisms and is a significant factor in the evolution of many organisms, including the development of mitochondria in eukaryotic cells.

Question 9

A viroid is

Accepted Answer

Viroids are indeed naked RNA molecules, but they are known to infect plants specifically, not animals.

Question 10

Prion diseases

Accepted Answer

Prion diseases are caused by misfolded proteins that can induce other proteins to misfold, leading to diseases such as Creutzfeldt-Jakob disease in humans. They do not involve mRNA and primarily affect the brain, not the liver.

Question 11

Which of the following is a method for the transmission of prion diseases?

Accepted Answer

The answer of Which of the following is a method...

Question 12

Label the indicated parts of the bacteriophage.
  a. ____________________
b. ____________________
c. ____________________
d. ____________________

Accepted Answer

The answer of Label the indicated parts of the bacteriophage.
...

Question 13

In this figure, depicting the series of events during a viral infection and release from a cell, what is happening at stage 3?

Accepted Answer

The answer of In this figure, depicting the series of...

Question 14

After reading the paragraph, answer the question(s) that follow(s).
Generally, we think of viruses as nasty little bits of business that arrive unwanted, take over our cellular functions, and then move along to their next victim. Recently, however, it was discovered that the human genome actually contains about half a million 'viral fossils.' Indeed, about 8% of human DNA appears to originate from viral DNA that became permanently incorporated into the human genome. And furthermore, in some cases, identical viral fossils have been found in the chimpanzee genome. These incredible findings suggest that we might need to take a broader view of how viruses and people truly interact and have done over the millennia.
-Based on these observations we might conclude that, were we able to wipe out all viruses from the face of the earth, then

Accepted Answer

Viruses, by integrating their DNA into our genome, contribute to genetic variability, as indicated by the presence of viral DNA in human and chimpanzee genomes.

Question 15

After reading the paragraph, answer the question(s) that follow(s).
Generally, we think of viruses as nasty little bits of business that arrive unwanted, take over our cellular functions, and then move along to their next victim. Recently, however, it was discovered that the human genome actually contains about half a million 'viral fossils.' Indeed, about 8% of human DNA appears to originate from viral DNA that became permanently incorporated into the human genome. And furthermore, in some cases, identical viral fossils have been found in the chimpanzee genome. These incredible findings suggest that we might need to take a broader view of how viruses and people truly interact and have done over the millennia.
-These observations also suggest that

Accepted Answer

The paragraph suggests that the presence of viral DNA in the human genome and its similarity to that in the chimpanzee genome indicates a long history of coevolution between humans and viruses, rather than viruses being a recent phenomenon or unable to infect germ cells.

Quiz 7: Viruses and Other Acellular Life

Some viruses, like human papilloma virus (HPV) can cause cancer. How does HPV do this?

Why do viruses often seem to emerge from nowhere to become major public health scares in Canada?

Animal cells and viruses are in an ongoing 'arms race' to prevent and facilitate infection, respectively. Of the following evolved changes to the host, which do you think would be most effective at limiting viral infection?

The deadliest viruses for a population of people tend to be those which

The genetic reshuffling of DNA from multiple viruses to create new and sometimes deadly viruses is an example of

In horizontal gene transfer a gene can be transferred between

The mitochondrial RNA polymerase of human cells is related to the T7 bacteriophage RNA polymerase. This appears, therefore, to be a case of

A viroid is

Prion diseases

Which of the following is a method for the transmission of prion diseases?

Label the indicated parts of the bacteriophage. a. b. c. d.

In this figure, depicting the series of events during a viral infection and release from a cell, what is happening at stage 3?

Quiz 7: Viruses and Other Acellular Life

Some viruses, like human papilloma virus (HPV) can cause cancer. How does HPV do this?

Why do viruses often seem to emerge from nowhere to become major public health scares in Canada?

Animal cells and viruses are in an ongoing 'arms race' to prevent and facilitate infection, respectively. Of the following evolved changes to the host, which do you think would be most effective at limiting viral infection?

The deadliest viruses for a population of people tend to be those which

The genetic reshuffling of DNA from multiple viruses to create new and sometimes deadly viruses is an example of

In horizontal gene transfer a gene can be transferred between

The mitochondrial RNA polymerase of human cells is related to the T7 bacteriophage RNA polymerase. This appears, therefore, to be a case of

A viroid is

Prion diseases

Which of the following is a method for the transmission of prion diseases?

Label the indicated parts of the bacteriophage. a. ____________________ b. ____________________ c. ____________________ d. ____________________

In this figure, depicting the series of events during a viral infection and release from a cell, what is happening at stage 3?

Label the indicated parts of the bacteriophage. a. b. c. d.