Question

Which bonds of ATP have high energy bonds?
A) C-C
B) C-O
C) C-N
D) P-P

Answer 1

Hint: ATP is the primary energy currency of the cell. It is a nucleotide formed by the combination of adenine as the nitrogenous base, ribose sugar and the triphosphates. It is found in free cells that break its high energy phosphate bond in order to form energy.

Complete answer: The high energy phosphate bonds break to form ADP (Adenosine diphosphate) and AMP (Adenosine monophosphate). It is a hydrolysis reaction that occurs at extreme pH. Hydrolysis of ATP usually occurs to provide energy for many metabolic reactions. ATP has three phosphates groups, out of which one is directly attached to the ribose, forming the phosphate ester bond and it has low energy level. The bond that is formed between the two phosphate groups is a phosphoanhydride bond. It is considered to be a high energy bond. The bond between the beta and gamma phosphate is also considered to be a ‘high-energy’ bond. This is because when the bond breaks, the ATP (Adenosine Triphosphate) and water molecules produce ADP and one inorganic phosphate (Pi). This reaction is called hydrolysis (hydro=water and lysis=separation) because it consumes a water molecule.
Thus, option D is the correct answer.

Note: ATP has only two high energy phosphoanhydride bonds. The two bonds between the phosphates i.e. the phosphoanhydride bonds have equal high energy. The energy released by the breaking of bonds is used by the cell for cellular activities. So, the more the number of bonds, the more potential energy the cell will contain.