LECTURE 9 Flashcards
Metabolism in cell
Totality of chemical reactions in cell
Energy definition
Capacity for change, energy changes are associated with change in chemical structures and properties of molecules.
Two types of energy forms
1) kinetic energy
2) potential energy
Potential energy examples
Chemical energy, concentration gradients, electrical potential.
All reaction happen _____ in the …
Spontaneous in the direction that increase the entropy
Formula for change in free energy
Delta G = G final - G initial
If a reaction I’d spontaneous then G (free energy) is
Negative
If DELTA G is negative then some energy has been lost as
Entropy
In a closed system, the quantity of E
does not change, but the E can flow in different atoms
In every E transfer, some E is
Lost (as heat sometimes)
Free energy
Energy available to do work
In closed system, with multiple E transfers,
Free E (G) decreases and useful E increases
Entropy is always was ______ in the universe
Increasing
Entropy
A measure of disorder in the universe, and unuseful energy
Every E transfer makes the universe more
Disordered
Randomness in the universe ________ over time
Increases
When G < 0, then its
Exergonic
Exergonic
Proceeds with net release off free E and is spontaneous
When G > 0 then its
Endergonic
Endergonic
Absorbs free E from its surrounding tons and is NON-spontaneous
How do cells increase order
Reactions are coupled
If two systems change in a coupled fashion,
the net free E change of the combines systems determines f the reaction will proceed.
What is considered the lowest grade of energy
Heat
Heat increases the
Random, unordered movement of molecules
Heat is difficult to store or harness to do work, so its only useful it its
Concentrated
What increases in a chemical reaction ?
Entropy
Systems tend to move towards an increase in
Entropy
More order,
Lower entropy
Less order
Higher entropy
Order and entropy are
Inversed variables
_______ in the universe is always increasing
Entropy
E is required for ______in living things, but ______ still increases
Energy, entropy
Systems with higher free energy have
Complex, organized, non-random and low entropy
Systems with low free energy are
Disorganized, random, and high entropy (less E for work)
Formula for calculating G (free energy)
G = H = TS
Entropy symbol
S
If free energy and enthalpy are both (-) and everything else (+), then
- Energetically favourable
- entropically favourable
- spontaneous
If temp and entropy (-) and energy thing else (+), then
- energetically unfavourable
- entropically unfavourable
- NON-spontaneous
Free energy being (+/-) when everything else positive, then
- energetically unfavourable
- entropically favourable
- spontaneous at high T
Free energy is (-/+), enthalpy, temp, entropy are both (-), then
- energetically favourable
- entropically favourable
- spontaneous at low temp
Enthalpy
Total potential energy in system
Negative G =
Spontaneous reaction
Spontaneous
Change that does not require a net increase in energy
