If a virus attacks a cell, which of the following is most likely to occur first?

• A. The virus synthesizes new viral proteins in the cytoplasm
• B. The virus attaches to specific receptors on the cell surface
• C. The cell immediately undergoes apoptosis
• D. The cell releases interferons to neighboring cells

Answer: (B)

Verified step by step guidance

1. Understand the initial interaction between a virus and a host cell: viruses must first recognize and bind to specific molecules on the cell surface to gain entry.
2. Identify that viral attachment involves the virus binding to specific receptors on the cell membrane, which is a highly selective and necessary first step before any internal processes can occur.
3. Recognize that synthesis of viral proteins happens only after the virus has successfully entered the cell and released its genetic material.
4. Note that apoptosis (programmed cell death) and interferon release are cellular responses that typically occur after the virus has been detected inside the cell or after infection has progressed.
5. Conclude that the earliest event in viral infection is the attachment of the virus to specific receptors on the cell surface, enabling subsequent steps of viral entry and replication.