Ch 21 Viral Replication

Question 1

True or False: Viruses do not require a host for reproduction

Answer 1

False

Question 2

How do bacteriophages attach to host cells?

Answer 2

Cell-surface receptors

Question 3

True or False: Bacteriophages only inject their genome into the host cell and the capsid remains outside

Answer 3

True

Question 4

What is the lytic cycle?

Answer 4

Bacteriophage replicates quickly then kills the host

Question 5

What is the lysogenic cycle?

Answer 5

Integrates into cell chromosome in a dormant phase but it can become lytic

Question 6

What causes the lysogenic cycle to become lytic?

Answer 6

A threat to the host cell (survival)

Question 7

How have bacteria evolved to prevent bacteriophage infection?

Answer 7

Genetic resistance, restriction endonucleases, CRISPR

Question 8

Virulent replication: How are early genes transcribed?

Answer 8

By host RNA polymerase

Question 9

Where is phage T4 genome synthesized?

Answer 9

Within the host cell by rolling-circle replication

Question 10

What do the late genes do?

Answer 10

Encode lysozyme to produce mature phages

Question 11

How is a phage particle assembled?

Answer 11

The convergence of head, tail, and tail fibers pathways

Question 12

True or False: Viruses develop mutations whilst assembling

Answer 12

True

Question 13

What are oncogenic viruses?

Answer 13

Viruses that transform the host cell to become cancerous

Question 14

True or False: Infected plants cannot lytic burst

Answer 14

True their cell wall is thick enough to prevent this