3-Energy and Thermodynamics Flashcards
Life at the Cellular Level
Describe the fundamental laws of thermodynamics.
1st Law of thermodynamics;
Energy can change into lots of different forms but the energy of the universe will remain constant.
2nd Law of thermodynamics;
All energy transformations ultimately leads to more disorder in the universe, i.e. there is an increase in entropy (S).
Define ‘Gibbs free energy’
‘Useful’ free energy in a closed system.
It can be defined by 3 quantities;
Enthalpy (H)
Entropy (S)
Absolute temperature (T)
Define “free energy change”.
Free energy change is used to define the spontaneity of a reaction.
Describe what must happen within a system to get a spontaneous reaction.
The system must give up energy (e.g. spontaneously losing potential energy)
There must be an increase in entropy (e.g. spontaneously losing potential energy)
Define the term ‘reaction coupling’.
Cells use reaction or energy coupling to carry out thermodynamically unfavourable reactions.
Define metabolism.
“The chemical processes in a living organism by which food is used for tissue growth or energy production”
Metabolism is a continuous flow of energy and matter, and involves flow through
intermediary metabolites, and through pathways of enzyme-catalysed reactions
Define catabolism.
Catabolism is the breaking down of complex molecules into simpler ones, energy is released in the form of ATP as this happens.
Define anabolism
Anabolism is the set of metabolic pathways that build more complex molecules from simpler ones, ATP is required in order for this to occur.
This process is generally (in isolation) endergenic.
Describe, in general terms, how metabolism, anabolism and catabolism are independent.
TO BE CONFIRMED……..
Describe the contributions to metabolic flow of ATP and ADP.
When ATP changes to ADP, free energy is produced, which is harnessed to drive the catabolic process to drive thermodynamically unfavoured reactions (+ve deltaG).
An exergonic (accompanied by the release of energy) catabolic pathway “saves” free energy within a system when forming ATP.
Endergonic anabolic pathway is “supplied” Free Energy within a system through conversion of ATP to ADP.
Describe ‘coupling’ in relation to ATP hydrolysis.
ATP allows anabolic, thermodynamically unfavourable reactions to proceed through
coupling of catabolic thermodynamically favourable reactions.
Describe the structures and contributions to metabolic flow of NADP, NAD, FAD.
TO BE CONFIRMED……
