ATP Cycle

Key Concepts

• ADP (Adenosine Diphosphate):
  • Consists of adenosine and two phosphate groups.
• ATP (Adenosine Triphosphate):
  • Consists of adenosine and three phosphate groups.
  • Has more energy than ADP.

Conversion Processes

ADP to ATP

• Process:
  • Requires addition of an inorganic phosphate.
  • Energy is absorbed to form ATP from ADP.
  • This is an endergonic reaction (energy absorbing reaction).

ATP to ADP

• Process:
  • Involves the removal of a phosphate group.
  • Energy is released when ATP is converted to ADP.
  • This is an exergonic reaction (energy releasing reaction).
  • Requires water, making it a hydrolysis reaction.

Reactions

• Hydrolysis Reaction:

  • ATP + Water → ADP + Phosphate Group + Energy
  • Example of an exergonic reaction.

• Dehydration Synthesis Reaction:

  • ADP + Inorganic Phosphate + Energy → ATP + Water
  • Involves forming a bond and releasing water.
  • Example of an endergonic reaction.

Functions of ATP

• ATP serves as a short-term energy storage.
• Energy released from ATP is used for:
  • Active transport
  • Synthesizing molecules
  • Driving other endergonic reactions

Importance

• ATP is known as the "energy currency" of the cell.
• Crucial for various cellular processes and functions.

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This summary provides a foundational understanding of the ATP cycle, highlighting its role in cellular energy management.