What is the main function of the viral capsid and envelope?

• A. To replicate the viral genome independently of the host
• B. To provide energy for viral replication
• C. To synthesize viral proteins during infection
• D. To protect the viral genetic material and facilitate attachment to host cells

Answer: (D)

Verified step by step guidance

1. Understand that the viral capsid is a protein shell that encases and protects the viral genetic material (DNA or RNA) from degradation in the external environment.
2. Recognize that the viral envelope, which is derived from the host cell membrane, surrounds some viruses and contains viral proteins that help the virus attach to and enter host cells.
3. Note that the capsid's protective role ensures the viral genome remains intact until it reaches a suitable host cell for infection.
4. Understand that the envelope's proteins facilitate the recognition and binding to specific receptors on the surface of host cells, enabling viral entry.
5. Conclude that the main function of the viral capsid and envelope is to protect the viral genetic material and facilitate attachment to host cells, rather than replicating the genome, providing energy, or synthesizing proteins.