Cell respiration - ATP Flashcards
What is the primary role of Adenosine Triphosphate (ATP) in living organisms?
Provides energy for life processes such as movement, nutrition, and excretion
How is energy released during cellular respiration transferred to ATP?
In a series of small steps
What is lost at each step of energy transfer during respiration?
Heat
Why is heat loss during respiration important for endotherms?
Used to regulate body temperature
What is ATP described as?
A universal energy currency
What are the two components of the term ‘universal energy currency’?
- Universal: used in all organisms
- Currency: reused for different reactions
What enzyme is responsible for the hydrolysis of ATP?
ATPase
What is a benefit of the hydrolysis of ATP?
Releases a useful quantity of energy without waste
What is the stability of ATP at cellular pH levels?
Relatively stable
What are the components of ATP?
- Ribose sugar
- Adenine base
- Three phosphate groups
What is one benefit of ATP being a stable molecule?
Doesn’t break down unless a catalyst (ATPase) is present
How can ATP be recycled?
Reformed from ADP and inorganic phosphate (Pi)
What is the significance of ATP hydrolysis being quick and easy?
Allows cells to respond to sudden increases in energy demand
Why is ATP soluble and able to move easily within cells?
Can transport energy to different areas of the cell
What are phosphorylated intermediates?
Make metabolites more reactive and lower activation energy required for reactions
List some life processes reliant on ATP.
- Anabolic reactions to synthesize larger molecules
- Active transport across cell membranes
- Movement of the entire cell
- Movement of cell components like chromosomes
What does ATP convert to when it releases energy?
Adenosine diphosphate (ADP) and a phosphate ion (Pi)
Why is ATP not stored in living organisms?
It is a very reactive molecule
What are short-term and long-term energy storage molecules?
- Short-term: glucose and fatty acids
- Long-term: glycogen, starch, and triglycerides
What happens during the hydrolysis of ATP?
ADP and phosphate are produced
How much energy is released when one phosphate group is removed from ATP?
Approximately 30.5 kJ mol -1
What is produced when the second phosphate group is removed from ADP?
AMP
What is the energy release when the third phosphate group is removed from AMP?
14.2 kJ mol -1
How much ATP do humans use on average in a day?
More than 50 kg
