Metabolic Processes - Coupled Reactions and Metabolic Pathways + Energy Transfer in Living Systems Flashcards
Coupled reactions
In order to facilitate anabolic and catabolic pathways, reactions are coupled - an exergonic reaction provides the energy needed for an endergonic reaction to take place
Anabolic pathway
A pathway in which energy is supplied to build complex molecules from simple molecules
Catabolic pathway
A pathway in which energy is released and complex molecules are broken down into simpler molecules
How does the structure of ATP allow it to store free energy
- ATP has an unstable triphosphate tail
- This instability is due to the repulsive forces between the crowded phosphate molecules
- When the terminal phosphate is hydrolyzed (broken off through hydrolysis), the molecules becomes more stable and energy is released (exergonic reaction)
What happens during a phosphorylation reaction?
- Energy released during hydrolysis of ATP can be transferred to another molecule via the released inorganic phosphate group
- Inorganic phosphate binds to the other molecule, energizing it
What happens during a redox reaction?
- One or more electrons are transferred from one chemical to another (2 reactions at the same time)
- Reduction: a chemical gaining one or more electrons
- Oxidation: a chemical losing one or more electrons
What is the role of electron carriers in redox reactions?
Electron carriers transport electrons from one compound to another during redox reactions