Lytic Cycle

Bacterial host cell 2. Entry 3. Replication Date Master 4. Assembly 5. Lysis and Release 1. Attachment Bacterial chromosome 25 Nucleic acid Bacteriophage Name Class Basic Concepts Lytic Cycle Name Date Basic Concepts Worksheet 25 Class Lytic Cycle 1. How is the viral nucleic acid core different from the nucleic acid of the bacterial host? The viral nucleic acid core may differ from the nucleic acid of the bacterial host in terms of its structure, sequence, or composition. Additionally, viral nucleic acids often contain specific sequences or genes that are characteristic of the virus but not present in the host. 2. What must happen in order for a virus to attach to the host cell? In order for a virus to attach to the host cell, specific viral proteins or molecules on the surface of the virus must bind to complementary receptors or attachment sites on the surface of the host cell. 3. Why would the bacteriophage shown in the transparency not be able to enter any other type of cell? The bacteriophage shown in the transparency would not be able to enter any other type of cell because its attachment proteins are specific to receptors found on bacterial cells. Other cell types would lack these receptors, preventing the virus from attaching and entering. 4. Look at step 2 in the lytic cycle. What method of entry does the virus appear to be using? Describe another method of entry used by viruses. In step 2 of the lytic cycle, the virus appears to be using direct penetration or injection to enter the host cell. Another method of entry used by viruses is endocytosis, where the entire virus particle is engulfed by the host cell's membrane and internalized into the cell. 5. In which step of the lytic cycle is the host cell destroyed? The host cell is destroyed during step 5 of the lytic cycle when the newly assembled viruses burst out of the cell, causing lysis and cell death. 6. What must happen before new virus particles can be assembled? Before new virus particles can be assembled, viral nucleic acid and protein components must be synthesized within the host cell using the cell's machinery. 7. What does the virus use from the host cell in order to make new viral nucleic acid and protein coats? The virus uses various resources from the host cell, including nucleotides, amino acids, enzymes, and cellular organelles, to make new viral nucleic acid and protein coats. 8. How does the cycle shown in the transparency support the claim that viruses are not living things? The cycle shown in the transparency supports the claim that viruses are not living things because they lack the ability to carry out metabolic processes, replicate independently, or respond to stimuli. Instead, they rely entirely on host cells for replication and are considered obligate intracellular parasites.