Which of the following is a key difference between the multiplication cycle of animal viruses and bacteriophages?

• A. Animal viruses typically enter host cells by endocytosis or membrane fusion, while bacteriophages inject their genetic material into the host cell.
• B. Animal viruses and bacteriophages both use tail fibers to attach to host cells.
• C. Both animal viruses and bacteriophages always lyse the host cell during release.
• D. Bacteriophages replicate only in the nucleus of the host cell, while animal viruses replicate in the cytoplasm.

Answer: (A)

Verified step by step guidance

1. Step 1: Understand the general process of viral multiplication, which includes attachment, entry, replication, assembly, and release.
2. Step 2: Identify how animal viruses enter host cells, noting that they typically use mechanisms such as endocytosis or membrane fusion to bring the entire virus particle inside the host cell.
3. Step 3: Recognize that bacteriophages differ by injecting only their genetic material into the bacterial host cell, leaving the capsid outside.
4. Step 4: Compare the attachment mechanisms, noting that bacteriophages use tail fibers to attach to bacterial cells, while animal viruses may use different surface proteins for attachment.
5. Step 5: Understand that the release mechanisms and replication sites differ between these viruses, but the key difference highlighted is the method of entry into the host cell.