Notes for A2.3.4 Lysogenic cycle of a virus (HL) - IB | RevisionDojo
A2.3.4 Lysogenic cycle of a virus (HL) Notes
The Lysogenic Cycle: Viral Dormancy and Integration
Bacteriophage lambda can switch between two distinct life cycles: the lytic cycle and the lysogenic cycle.
The lysogenic cycle
Step-By-Step Breakdown Of The Lysogenic Cycle
Step 1: Attachment
Bacteriophage λ attaches to E. coli using tail proteins that bind specifically to maltoporin, a protein in the bacterial outer membrane.
Step 2: DNA Entry (Penetration)
The phage contracts its tail sheath like a syringe, injecting viral DNA into the bacterial cytoplasm.
The viral DNA enters as a linear molecule with sticky ends, which rapidly circularizes inside the host.
Only the DNA enters, the capsid remains outside.
Step 3: Integration into Host Genome
The enzyme integrase (encoded by the phage) inserts viral DNA into a specific site in the bacterial chromosome.
Once integrated, the viral DNA is called a prophage.
Step 4: Host Cell Division (Prophage Replication)
The bacterial cell continues normal growth and reproduction.
The prophage DNA is replicated passively alongside host DNA.
Unlock the rest of this chapter with aFreeaccount
Nice try, unfortunately this paywall isn't as easy to bypass as you think. Want to help devleop the site? Join the team at https://revisiondojo.com/join-us. exercitation voluptate cillum ullamco excepteur sint officia do tempor Lorem irure minim Lorem elit id voluptate reprehenderit voluptate laboris in nostrud qui non Lorem nostrud laborum culpa sit occaecat reprehenderit
Definition
Paywall
(on a website) an arrangement whereby access is restricted to users who have paid to subscribe to the site.
anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.
Duis aute irure dolor in reprehenderit
Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
Note
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam quis nostrud exercitation.
Excepteur sint occaecat cupidatat non proident
Nemo enim ipsam voluptatem quia voluptas sit aspernatur aut odit aut fugit, sed quia consequuntur magni dolores eos qui ratione voluptatem sequi nesciunt. Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit.
Tip
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.
Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris.
Duis aute irure dolor in reprehenderit in voluptate velit esse cillum.
Questions
Recap questions
1 of 5
Question 1
Recap question
In a population of E. coli carrying a lambda prophage under non-stress conditions, what mechanism ensures each daughter cell inherits the viral genome?
End of article
Want a cheatsheet?
View a summary cheatsheet for A2.3 Viruses (HL)
Flashcards
Remember key concepts with flashcards
18 flashcards
What are the two life cycles of bacteriophage lambda?
Lesson
Recap your knowledge with an interactive lesson
8 minute activity
Note
Introduction to Bacteriophage Lambda
Bacteriophage Lambda is a virus that infects Escherichia coli bacteria.
It can switch between two life cycles: the lytic cycle and the lysogenic cycle.
This phage is a key model for studying virus-host interactions and gene regulation.
DefinitionBacteriophage LambdaA virus that infects bacteria, specifically E. coli, and can alternate between lytic and lysogenic life cycles.
AnalogyThink of bacteriophage lambda as a spy that can either launch an attack (lytic cycle) or go undercover (lysogenic cycle) within its host.
NoteBacteriophage lambda is a temperate phage, meaning it can choose between lytic and lysogenic cycles based on environmental conditions.
