Question

Viruses are interesting organisms that have unique genetic properties including the facts that the genetic material can be either single-or double-stranded and that the genetic material can be either DNA or RNA. On the shuttle bus to campus one morning, you discovered a new viral particle and determined it's base composition to be 25% adenine, 25% cytosine, 20% uracil and 30% guanine. Based on this result, you suggest that the viral genetic material is most probably _____

a. single-stranded DNA.
d. double-stranded RNA.
b. double-stranded DNA.
e. protein.
c. single-stranded RNA.

Answer 1

Based on the base composition (25% adenine, 25% cytosine, 20% uracil, and 30% guanine) and the absence of thymine, the viral genetic material is most probably single-stranded RNA. The answer is c. single-stranded RNA.

Step-by-step explanation:

The base composition of the viral particle suggests that it contains genetic material composed of nucleotides adenine (A), cytosine (C), uracil (U), and guanine (G). In DNA, adenine pairs with thymine (T), while in RNA, adenine pairs with uracil. The presence of uracil instead of thymine indicates an RNA-based genetic material.

Moreover, the given percentages (20% uracil) align with RNA's composition. RNA can be single-stranded or double-stranded. In this case, the absence of thymine and the equal distribution of adenine, cytosine, uracil, and guanine suggest a single-stranded RNA composition.

Therefore, based on the base composition, the viral genetic material is most probably: c. single-stranded RNA.

This deduction aligns with the unique genetic properties of viruses, which can possess either single-stranded RNA, double-stranded RNA, single-stranded DNA, or double-stranded DNA genomes.