Application/Concepts for Thermodynamics, Free Energy and Bioenergetics Flashcards
(20 cards)
What is the 1st Law of Thermodynamics?
energy cannot be created nor destroyed, only converted from one form to another
What are the 5 forms of energy?
- heat
- kinetic
- potentisl
- chemical
- electromagnetic
What is the 2nd Law of Thermodynamics?
the universe (or any isolated system) is constantly moving towards disorder
How do systems change?
they change spontaneously towards arrangements that have the greatest probability
What is the negative side to order within a cell?
if it offset by an increase in disorder in the environment outisde of the cell
What are the two things out of the ‘food’ taken up by cells?
- energy\2. building blocks (atoms)
What occurs during a catabolic pathway?
the pathways break down larger molecules into smaller one
-polymer–> monomer
What occurs during a anabolic pathway?
the pathway builds larger molceules from smaller ones
-monomer –> polymer
When is the only time a chemical reaction can proceed?
if the final result is an increase in disorder (entropy)
When does disorder increase?
when useful energy (can be used to do work) is dissipated as heat
-the useful energy is free energy (or G)
Where does Free energy, G, come from?
movement of atoms and energy stored in bonds
What happens when deltaG is less than 0? greater than 0?
-when less than 0, the free energy decreases, and entropy decreases
-when greater than 0, free energy increases, and entropy decreases
Is delta G constant? if not, what can affect it?
No it is not canstant
-can be affected by environmental things such as temp, pressure concentrattion
-can also be affected by the chemical structure of the molecule (deltaG^0)
When does delta G^0 determine the reaction?
If X and Y are present at equal concentrations at the same conditions, Y–> X is the favorable rxn
-as most of Y gets converted to X, the rxn reaches equilibrium and deltaG will go to 0
What is deltaG^0?
it is the standard free-energy change of a rxn, which is used to compare deltaG among different reactions
What can happen to reactions that are energetically unfavorable?
they can be couple, or linked, to second, energetically favorable reactions
What can be used to physically couple reactions?
enzymes
What are examples of activated carriers?
ATP, GTP, NADH, NADHP
What do enzymes do?
they promote catalysis for spontaneous/favorable reactions, and lower the activation energy
What makes enzymes specific?
enzymes are specific to their substrate, which is facilitated by the shape and structure of the enxyme
