ATP adenosine triphosphate

Vocabulary flashcards covering ATP structure, the role of its components, the bonds that store energy, and the cellular ATP/ADP energy cycle.

ATP (adenosine triphosphate)

A nucleotide-like molecule with a ribose sugar, adenine base, and three phosphate groups; the cell’s main energy currency; energy is released when the terminal phosphate bond is hydrolyzed.

Ribose

Five-carbon sugar in ATP; makes ATP more like RNA than DNA (ATP contains ribose, not deoxyribose).

Adenine

Nitrogenous base in ATP; paired with ribose to form the adenosine component of ATP.

Three phosphate groups (alpha, beta, gamma)

Attached to adenosine; carry negative charges and are held together by high-energy phosphoanhydride bonds that store energy.

Gamma phosphate

The third phosphate in ATP; energy release largely comes from cleavage of the bond between beta and gamma phosphates (ATP → ADP + Pi).

Phosphoanhydride bonds

High-energy bonds between phosphate groups in ATP; hydrolysis of these bonds provides cellular energy.

ADP (adenosine diphosphate)

Product of ATP hydrolysis when one phosphate is removed; can be re-phosphorylated to reform ATP.

ATP hydrolysis

The reaction where ATP loses a phosphate (to become ADP and Pi) and releases usable energy for cellular processes.

ATP is labile (volatile)

ATP is unstable and cannot be stored long-term; it must be continually regenerated to meet energy needs.

Oxygen dependence for ATP production

Efficient ATP generation relies on oxygen in aerobic respiration; without oxygen, ATP production is limited and turnover is reduced.