differentiate between the lysogenic and lytic cycles
A the host cell copies its own dna during the lytic cycle
B the virus injects dna into the host cell during the lysogenic cycle
C the host cell is destroyed during the lytic cycle
D viral proteins are synthesized during the lysogenic cycle
The correct differentiations are:
A: The host cell copies its own DNA during the lytic cycle.
C: The host cell is destroyed during the lytic cycle.
The incorrect statements are:
B: The virus injects DNA into the host cell during the lysogenic cycle. This is a characteristic of the lytic cycle, not the lysogenic cycle.
D: Viral proteins are synthesized during the lysogenic cycle. This is a characteristic of the lytic cycle, not the lysogenic cycle.
The correct differentiations between the lysogenic and lytic cycles are as follows:
Lysogenic Cycle:
B) In the lysogenic cycle, the virus injects its DNA into the host cell.
D) Viral proteins are synthesized during the lysogenic cycle.
Lytic Cycle:
A) During the lytic cycle, the host cell copies its own DNA.
C) The host cell is destroyed during the lytic cycle.
The correct answer is:
A) The host cell copies its own DNA during the lytic cycle.
To differentiate between the lysogenic and lytic cycles, it is important to understand that both cycles are stages of viral reproduction.
In the lytic cycle, the virus attaches to the host cell and injects its genetic material (either DNA or RNA) into the cell. Once inside, the viral genome takes control over the host cell's machinery, causing it to produce viral components (such as DNA, RNA, and proteins) instead of its usual cellular components. These components assemble and form new viral particles. Eventually, the host cell is ruptured or lysed, releasing the newly formed viruses to infect other cells. Therefore, option C is incorrect because the host cell is indeed destroyed during the lytic cycle.
On the other hand, in the lysogenic cycle, the virus also injects its genetic material into the host cell but instead of immediately taking control and replicating, the viral DNA integrates into the host cell's genome. Integrated viral DNA is called a prophage if it is of bacteriophage origin. The host cell then divides, and each daughter cell contains a copy of the viral DNA. Over time, under certain conditions (such as stress or environmental triggers), the integrated viral DNA can re-enter the lytic cycle, initiating the reproduction of new viral particles. During the lysogenic cycle, viral proteins are not synthesized or produced. Therefore, option D is incorrect.
In summary, the lytic cycle involves immediate replication and destruction of the host cell, while the lysogenic cycle involves integration of viral DNA into the host cell's genome, where it can remain dormant for extended periods of time.