Question

Question 25 (1 point) The polypeptide marked as POO can be found on cells infected with +RNA viruses. Question 25 options: A) True B) False

Question 26 (1 point) Negative strand RNA viruses can be replicated only if the infecting RNA brings along a transcriptase. Question 26 options: A) True B) False

Question 27 (1 point) What is the role of protooncogenes in theories of how viruses cause cancer? Question 27 options: A) They cause cancer viruses to replicate faster. B) They make cells more susceptible to infection by cancer-causing viruses. C) They prevent the immune system from attacking cancer-causing viruses. D) They prevent cancer-causing viruses from leaving the cell. E) They play a role in the control of cell division.

Question 28 (1 point) Some viruses do not cause any apparent permanent damage at all to cells they infect. Question 28 options: True False

Answer 1

25.No polypeptide marked as POO can be found on cells infected with +RNA viruses.Thus the answer is :

Option B)False.

26.All of the negative-strand RNA viruses have an enzyme, called an RNA-dependent RNA polymerase (transcriptase), which must first catalyze the synthesis of complementary mRNA from the virion genomic RNA before viral protein synthesis can occur.Thus the answer is:

Option A) True.

27.Cancer-causing retroviruses Retroviral insertion can convert a proto-oncogene, integral to the control of cell division, into an oncogene.This oncogene undergoes uncontrolled celluler division causing cancer state.Thus the answer is:

Option E) They play a role in the control of cell division.

28.Some viruses cause no apparent changes to the infected cell. For example in Herpes virus,Cells in which the virus is latent (inactive) show few signs of infection and often function normally. This causes persistent infections and the virus is often dormant for many months or years.Thus the answer is:

Option A)True.