Virus Replication Mechanisms: Lytic and Lysogenic Cycles Explained

The video explains two main methods by which viruses replicate within host cells: the lytic and lysogenic cycles. In the lytic cycle, a virus injects its DNA into a host cell, hijacks the cell's machinery to replicate itself, and eventually causes the cell to burst, releasing new viruses. The lysogenic cycle involves the viral DNA integrating into the host's genome, remaining dormant until triggered to enter the lytic cycle. This process can lead to the spread of viral DNA across generations of cells.

What is the primary focus of the video?

• The structure of viruses

• The history of viral infections

• Two ways viruses replicate using cells

• The immune response to viruses

In the lytic cycle, what does the virus use to replicate its DNA?

• The cell's mitochondria

• The cell's ribosomes

• The cell's membrane

• The cell's nucleus

What happens to the host cell at the end of the lytic cycle?

• It repairs itself

• It bursts and dies

• It divides into two

• It becomes dormant

What is a common outcome of the lytic cycle for the host cell?

• The cell repairs its DNA

• The cell bursts and releases new viruses

• The cell becomes immune to viruses

• The cell becomes cancerous

How does the lysogenic cycle differ from the lytic cycle initially?

• The virus destroys the cell's ribosomes

• The viral DNA integrates into the host's DNA

• The virus exits the cell without replication

• The virus immediately replicates

What is a characteristic of the lysogenic cycle?

• Formation of viral proteins

• Immediate destruction of the host cell

• Integration of viral DNA into the host genome

• Rapid replication of viral particles

What can cause the viral DNA in the lysogenic cycle to activate?

• An increase in cell size

• A decrease in temperature

• A lack of nutrients

• Environmental stress

What is a potential result of viral DNA integration in the lysogenic cycle?

• The host cell gains new genetic traits

• The host cell loses its ability to divide

• The host cell becomes resistant to all viruses

• The host cell becomes a virus

What is a possible reason for the activation of viral DNA in the lysogenic cycle?

• Stress or environmental changes

• A mutation in the viral DNA

• A decrease in host cell size

• A change in the host's diet

What is a significant difference between the lytic and lysogenic cycles?

• The lytic cycle results in the production of new viruses

• The lysogenic cycle does not involve viral DNA

• The lytic cycle involves integration into the host genome

• The lysogenic cycle results in immediate cell death