Chapter 24.4.1 (Exam 4) Viruses

Question 1

Name some important characteristics of viruses.

Answer 1

Not cellular, derived from cells of other living organisms

Have DNA and RNA

Infect all cellular forms of life

Replicate, mutate, evolve (coevolution), and interact with other organisms,

Evolve independently of other organisms

Question 2

Why is virus phylogeny difficult to resolve?

Answer 2

Viral genomes are tiny, which restricts analyses that can be done

Rapid mutation rate and evolution cloud evolutionary relationships

There are no known viral fossils

They are very diverse

Question 3

How are viruses classified?

Answer 3

Genome structure

Question 4

What are two ways of classifying viruses?

Answer 4

Genome consisting of DNA or RNA

Single or double stranded genetic information

Question 5

What are some different classifications of viruses?

Answer 5

Negative-sense single-stranded RNA viruses

Positive-sense single-stranded RNA viruses

RNA Retroviruses

Double-stranded RNA viruses

Double-stranded DNA viruses

Question 6

Name one negative-sense single-stranded RNA virus.

Answer 6

Influenza

Question 7

Name one positive-sense single-stranded RNA virus.

Answer 7

Coronavirus

Question 8

Name one RNA retrovirus.

Answer 8

HIV

Question 9

Name one double-stranded DNA virus.

Answer 9

Bacteriophage T2