Types of Viruses

Question 1

DNA Viruses example

Answer 1

Human Papillomavirus
§ Causes Warts
§ Non-malignant tumors
§ Tree-like warts can develop if an infection is coupled with a genetic disorder (immune system is too weak to fight them off)

Question 2

RNA Viruses

Answer 2

→ Replication usually takes place in the cytoplasm
→ RNA viruses can be placed into four different groups depending on their modes of replication
→ The polarity of single stranded RNA viruses largely determines the replicative mechanism
→ The other major criterion is whether the genetic material is single stranded or double stranded
→ All RNA viruses use their own RNA replicase enzymes to create copies of their genomes

Question 3

RNA virus example

Answer 3

Rubella
▪ Icosahedral shaped virus
▪ SS RNA
▪ Causes red rash and fever (Rubella German Measles)
▪ Can cause heart failure in an infected infant
▪ Vaccination possible
▪ Viral entry via membrane fusion (and it uses RNA polymerase)

Question 4

Viruses & Malignancy

Answer 4

Some viruses can cause malignancy:
▪ In chickens: a certain type of leukemia could be transmitted to previously healthy birds from those with the disease
▪ Also responsible for some human cancer:
□ Papilloma wart virus and cervical cancer
□ Epstein-Barr virus and Burkitt’s lymphoma