Chapter 1

Question 1

What is the first step in the viral infection process?

Answer 1

Adhesion of the viral particle on its host cell surface

Question 2

What do all viruses exploit to reproduce?

Answer 2

Host cell metabolism

Question 3

What are the two cycles that a virus can choose after injecting its nucleic acid?

Answer 3

• Lytic cycle
• Lysogenic cycle

Question 4

What mediates the infection process for HIV?

Answer 4

CD4 receptor on T4 lymphocytes

Question 5

What is hemagglutinin associated with in influenza virus?

Answer 5

Recognition with glycophorin A at the host cell membrane

Question 6

What is injected into the host cell after viral adhesion?

Answer 6

Viral nucleic acid and associated proteins

Question 7

What happens if the virus has a lipid bilayer during the injection process?

Answer 7

Fusion releases the whole capsid into the cytoplasm

Question 8

What is the role of reverse transcriptase in retroviruses?

Answer 8

Retrotranscribes viral RNA into DNA

Question 9

What is the term for viral DNA integrated into the host’s chromosome?

Answer 9

Provirus

Question 10

What is the state of the host cell referred to when it contains integrated viral DNA?

Answer 10

Lysogenic

Question 11

What happens during cell division of a lysogenic cell?

Answer 11

Integrated DNA replicates along with the host chromosome

Question 12

What occurs in the lytic cycle regarding the cell’s metabolism?

Answer 12

Deviated by specific viral proteins to favor viral gene transcription

Question 13

What is formed when viral nucleic acids and capsid proteins assemble?

Answer 13

New viral particles

Question 14

True or False: Lysogenic cells can revert to the lytic cycle.

Answer 14

True

Question 15

What can trigger a lysogenic cell to switch to the lytic cycle?

Answer 15

Diverse signals from the surrounding medium (e.g. UV irradiation)