Nucleotides are the building blocks of dna and rna. one nucleotide is also used in the high-energy molecule (pictured below)

Answer

          Nucleotide that use in the formation of high energy molecule is known as Adenine.

Explanation

         A single nucleotide is composed of three components, these are:

1. Pentose sugar

2. Phosphate group (phosphoric acid, and

3. Nitrogenous base.

Formation of high energy molecule

                  ATP stands for adenosine triphosphate is a type of mononucleotide. When adenine and nitrogenous base combine they give rise to another molecule known as adenosine.

                             Adenine + nitrogenous base →   Adenosine

However when one phosphate group is attached to it it become adenosine monophosphate.

                    Adenosine + posphate → Adenosine monophosphate

Similary when another phosphate is attached it become adenosine diphosphate and the addition of third phosphate lead to the formation of adenosine triphosphate.

Conclusion

               Thus is is cleared from the above discussion that Adenine is the main component of ATP (Energy rich molecule).

for a different answer set the answer would be because the oxygen in the water had depleted (apex)