Synthesis and Storage of ATP Molecules in Cell Cycle

G2 Phase
In the G2 phase of the cell cycle, cells prepare for division by synthesizing necessary proteins and organelles. However, ATP synthesis and storage do not occur in this phase.

S Phase
The S phase of the cell cycle is known as the synthesis phase, during which DNA replication takes place. While this phase is crucial for the duplication of genetic material, ATP synthesis and storage do not occur here either.

G1 Phase
The G1 phase is the first gap phase of the cell cycle, during which cells grow and carry out normal cellular functions. It is in this phase that cells primarily synthesize and store ATP molecules to provide energy for various cellular processes.

M Phase
The M phase, or mitosis phase, is when cells divide into two daughter cells. ATP is essential for this process to occur smoothly, but actual synthesis and storage of ATP molecules do not take place during this phase.

Conclusion
Therefore, the appropriate answer to the question would be G1 phase, as this is the stage of the cell cycle where synthesis and storage of ATP molecules primarily occur to provide energy for cellular functions and activities.