Question

What are two elements that nearly all animal viruses have?

1) Capsid and envelope
2) DNA and RNA
3) Nucleus and mitochondria
4) Cell wall and cell membrane

Answer 1

All animal viruses possess a capsid, which is a protective protein shell for their genetic material, and some may have an envelope derived from host cell membranes, which helps in entering host cells. The correct option is 1).

Step-by-step explanation:

The two elements that nearly all animal viruses have are a capsid and, in some cases, an envelope. Not all viruses possess an envelope, but all viruses are characterized by having a capsid, which is a protein coat that surrounds and protects their genetic material.

This genetic material can either be DNA or RNA, but not both. The capsid is made of protein subunits called capsomeres. The envelope, when present, is typically derived from the host cell's membrane and encompasses the capsid. It aids in the virus's entry into host cells. Therefore, the correct answer is 1) Capsid and envelope.