Question

State the dual nature of deoxyribonucleoside triphosphate during DNA replication?

Answer 1

Deoxyribonucleoside triphosphates (DNTPs) are molecules containing a nucleoside bound to three phosphates. They are a type of nucleotides of which nucleoside part is bound to three phosphates. They have dual purpose − act as substrates and provide energy also for DNA replication.
All four dNTPs - dATP, dGTP, dTTP and dCTP act as source of energy in replication. The two terminal phosphates in a deoxyribonucleoside triphosphates are high-energy phosphates. 5'-triphosphate of the nucleotide that is added to the existing DNA chain is broken first which releases the energy stored in two terminal phosphates. The remaining part of dNTPs participates in polymeriation of DNA molecule by acting as substrates.