chapter 13

19. How does a naked virus enter the animal host cell?
20. How does a naked virus leave a host cell? Mechanism of release?
21. How do enveloped viruses leave a host cell? Mechanism of release?
22. What is a retrovirus?​
23. What are the 3 enzymes made by a retrovirus? What is the function of each of those enzymes?
a. ____________________________________________________________________________________________
b. ____________________________________________________________________________________________
c. ____________________________________________________________________________________________
24. What are latent viruses?
25. In the oncogene theory of induction of cancer in humans (Fig 13.16), what is a protooncogene? 
26. What are the environmental factors contributing to the activation of oncogenes? 
27. Why is the repressor important in suppressing cancer?
28. Burkitt’s lymphoma
a. Epstein-Barr virus found in nearly all patients.
b. Cancer of B lymphocytes
c. What is the “Starry sky” pattern seen in a histological slide?
29. Hodgkin’s lymphoma
a. Rare
b. Know the signs: enlarged lymph nodes, the disease can spread to other areas
c. Starts as a painless swelling of the lymph nodes of groin, armpits, neck
d. Fever, chills, night sweat, weight loss, itchy skin
e. In most cases, can be cured.
30. Kaposi’s sarcoma
a. Tumor caused by the herpes virus
b. Outward indicator of AIDS – characteristic violaceous plaques on ala, tip of nose, and other areas of the body
c. Treatment involves HAART, that can lead to the regression of KS
31. Cervical Cancer
a. HPV is found in 90% cases
b. Mostly squamous cell carcinomas
c. HPV vaccine gives 75% protection
d. Signs and symptoms are vaginal bleeding, pelvic pain etc.
32. What is a viroid? 
a. Ans: Has RNA, lacks a protein capsid. Very small circular pieces of ssRNA.
33. Know what prions are. Know that the normal cellular PrP protein is made of alpha helices, but the prion PrP protein is made up of beta-pleated sheets. 
a. Know the various diseases caused by prions, such as BSE, vCJD, Kuru, Scrapie.
b. How is it transmitted?
c. How can prions be destroyed?