Lecture 2: Conjugate and non-conjugate driving forces Flashcards
What is flow?
Change is spatial distribution of something, e.g. matter, electrical charge, heat.
What is a driving force?
A thermodynamic flow in response to a thermodynamic force. The driving force is in response to the system’s non-equilibrium state.
What are conjugate flows/driving forces?
When the flow and driving force are of a similar type. For example:
- flow of matter driven by concentration gradient
- flow of electrical charge driven by voltage (gradient in charge)
- flow of heat driven by temperature gradient
What are non-conjugate flows/driving forces?
When the flow and driving force are of a non-similar type. For example:
- electric current driven by a concentration gradient
- chemical reaction driven by change in concentration of matter
What is energy transduction?
When a thermodynamic force stimulates a non-conjugate flow.
What is energy coupling?
When thermodynamically unfavourable reactions are driven by thermodynamically favourably reactions.
How can two reactions can coupled?
Reactions can be coupled by:
- common intermediates (majority of coupled reactions)
- conformational changed transmitted through through proteins
- flow of ions across membranes
What is metabolism?
The study of energy flow in a biological system.
The overall process through which a living organism can acquire and utilize free energy.
What affects the measurements of delta G of ATP in the cell?
The binding of magnesium ions, which have a high affinity for ATP.
What happens in a phosphoryl transfer reactions?
A phosphoryl group (O-PO3-2) is transferred to an alcohol, creating another alcohol.
R1-O-PO3-2 + R2-OH –> R1-OH + R2-O-PO3-2
Why are phosphoryl transfer reactions important?
The most important involve ATP and are important in providing energy for biosynthesis and active transport.
