Viruses are composed primarily of proteins and nucleic acids. Which of the following elements could be used to track the fate of viral proteins to determine if they entered the cell?

A) Phosphate because proteins contain phosphate, but nucleic acids do not
B) Sulfur because proteins contain sulfur, but nucleic acids do not
C) Nitrogen because proteins contain nitrogen, but nucleic acids do not
D) Oxygen because proteins contain oxygen, but nucleic acids do not

Nucleic Acids

are biopolymers essential for all known forms of life, including DNA and RNA, which carry genetic information and play roles in protein synthesis.

Phosphate

A chemical derivative of phosphoric acid, containing the phosphate ion, PO4^3-, which plays a significant role in biological molecules such as DNA and ATP.

Sulfur

A chemical element that is a nonmetal, yellow in color, with the atomic number 16, commonly found in minerals and used in various industrial processes.