Besides ATP, which other nucleotide is part of energy storage in cells?

• A. CTP
• B. GTP
• C. UTP
• D. TTP

Answer: (B)

Energy storage in cells revolves around high-energy phosphate bonds in nucleotide triphosphates. ATP is the primary currency, but another nucleotide that also carries energy is GTP. When GTP is hydrolyzed to GDP and inorganic phosphate, it releases energy that powers essential cellular tasks. In protein synthesis, GTP fuels the steps where the ribosome advances along mRNA and tRNA delivery; in many signaling pathways, GTP-binding proteins act as switches whose activity depends on GTP binding and hydrolysis. Other nucleotides like UTP, CTP, and TTP participate in specific biosynthetic roles (such as sugar activation or DNA synthesis) but are not the main energy carriers for general cellular processes in the same way as ATP and GTP.