RNA viruses require their own supply of certain enzymes because
a. Host cells rapidly destroy the viruses.
b. Host cells lack enzymes that can replicate the viral genome.
c. These enzymes translate viral mRNA into proteins.
d. These enzymes penetrate host cell membranes.

Verified step by step guidance

1. Understand that RNA viruses are a type of virus that have RNA as their genetic material, instead of DNA.
2. Recognize that for RNA viruses to replicate, they need to make copies of their RNA genome.
3. Consider the fact that host cells typically have enzymes that replicate DNA, not RNA. This is because most organisms use DNA as their genetic material.
4. Realize that RNA viruses must bring their own enzymes, such as RNA-dependent RNA polymerase, to replicate their RNA genome because host cells do not have these enzymes.
5. Conclude that the correct reason RNA viruses require their own supply of certain enzymes is because host cells lack enzymes that can replicate the viral genome.

Key Concepts

RNA Virus Replication

RNA viruses need specific enzymes to replicate their genomes because their genetic material is RNA, not DNA. Host cells typically lack the necessary enzymes to replicate RNA directly, as they are equipped to replicate DNA. Therefore, RNA viruses must carry or synthesize their own RNA-dependent RNA polymerase to ensure successful replication within the host.

Host Cell Enzymatic Limitations

Host cells are generally equipped with enzymes that replicate DNA and transcribe it into RNA, but they do not possess enzymes that can directly replicate RNA genomes. This limitation necessitates that RNA viruses bring their own replication machinery, as the host's cellular machinery cannot fulfill this role, highlighting the need for viral-specific enzymes.

Viral Enzymes and Protein Synthesis

While host cells have the machinery to translate mRNA into proteins, RNA viruses often encode their own enzymes to ensure efficient translation and processing of viral proteins. These enzymes can modify host cell processes to favor viral protein synthesis, ensuring the virus can replicate and assemble new viral particles effectively within the host.