lyctic cycle Flashcards
What is the role of the tail proteins in the lytic cycle of a bacteriophage?
The tail proteins of the bacteriophage bind to the outer surface of E. coli, allowing the virus to inject its DNA into the host cell.
How does the viral DNA enter the host cell in the lytic cycle?
The viral DNA enters the host cell through the tubular tail and then forms a circular structure after single-stranded ends link together.
What are the two possible cycles a virus can follow after entering a host cell?
The virus can follow either the Lysogenic cycle (where viral DNA integrates into bacterial DNA and no new viruses are made) or the Lytic cycle (where new viruses are produced and the host cell is destroyed).
What happens in the lytic cycle?
In the lytic cycle, the virus reproduces inside the host, eventually causing the host cell to burst and release new viruses, which kills the host cell.
Why is Bacteriophage λ considered virulent when it follows the lytic cycle?
Bacteriophage λ is virulent because it kills the host cell (E. coli), allowing it to spread but also risking the death of the virus if no new hosts are found.
Why is the lytic cycle disadvantageous for viruses in the long run?
The lytic cycle is disadvantageous because the virus kills its host, potentially leading to the destruction of the host population and making it harder for the virus to persist.
How does the lytic cycle affect the spread of plant and animal viruses?
In plant and animal viruses, the lytic cycle spreads the virus from cell to cell, often leading to increasing severity of the infection, which can be life-threatening if uncontrolled.
How does the host defend against viral infection in the lytic cycle?
The host’s immune system, like antibodies in humans, can fight off viruses, limiting the spread of infection and potentially preventing the virus from killing the host.
