I'd like to get to the bottom of lecture 4

Question 1

In what direction do spontaneous processes occur?

Answer 1

“Spontaneous processes occur in directions that increase the overall disorder of the universe.”

Maximum disorder is most probable.

Question 2

“active” conformations of a protein

Answer 2

The “active” conformations of proteins are typically highly ordered, discrete structures of relatively LOW entropy compared to the “unfolded” states of the proteins.

Question 3

exergonic

Answer 3

Processes with a negative free energy changes (-deltaG)

Question 4

endergonic

Answer 4

Processes with a positive free energy changes (+deltaG)

Question 5

thermodynamically favored process

Answer 5

tends in the direction that minimizes free energy (results in a negative deltaG); this is one way of
stating the second law of thermodynamics

Question 6

is Gibbs Free Energy related to chemical equilibrium?

Answer 6

yes, Gibbs Free Energy is dependent on the concentrations of the reactants and products of a reactions and thus, is related to “chemical equilibrium”.

Question 7

what does delta H depend on?

Answer 7

the numbers and kinds (covalent & non-covalent) of BONDS made and broken upon going from initial to final state.

Question 8

delta S depends on?

Answer 8

the mobilities and/or randomness of the system and surroundings upon going from initial to final state

Question 9

The more isoenergetic states for a system, the _______ the entropy of that system.

Answer 9

greater

Question 10

The equation deltaG = RT ln ([A]2/[A]1) predicts:

Answer 10

1. ) If [A]2 < [A]1, deltaG is negative; thus, transfer from region 1 to region 2 is favorable.
2. ) Conversely, for a system where [A]2 > [A]1, deltaG is positive; thus, transfer from region 1 to region 2 would not be favorable.
3. ) If is [A]2 = [A]1, deltaG is zero; thus, there is no net driving force in either direction for the transfer of A. The system is at equilibrium.

Question 11

From the analysis of deltaG = RT ln ([A]2/[A]1) , we can conclude that if a substance is able to pass through a membrane…

Answer 11

the direction of favorable transfer will always be from the region of higher concentration to the region of lower concentration

Question 12

Le Chatelier’s Principle

Answer 12

Any deviation from equilibrium stimulates a process that tends to restore the system to equilibrium. All isolated systems must therefore inevitably reach equilibrium”

Question 13

How do we get a thermodynamically unfavorable reaction to occur?

Answer 13

1. ) Coupling to a highly favorable reaction.

2. ) Maintaining a “steady-state” [products] far below the equilibrium [products]

Question 14

Driving an unfavorable process by coupling it to a favorable one requires the availability in ____ of _______ that can undergo reactions with _____________.

Answer 14

cells

compounds

large negative free energy changes.

Question 15

High-energy phosphate compounds have very large __________ free energies of hydrolysis.

Answer 15

negative

Question 16

most important high energy compounds?

Answer 16

phosphates, which can undergo hydrolytic release of their phosphate groups in aqueous solution.

Question 17

energy transducers in the cell

Answer 17

helps drive an unfavorable process by coupling it to a favorable one.

This requires the availability in cells of compounds that can undergo reactions with large negative free energy changes.

Question 18

The orthophosphate ion

Answer 18

HPO_4^-2

often abbreviated as Pi (inorganic phosphate), is capable of a wide variety of resonance forms

Resonance stabilization applies in all of the phosphate hydrolysis reactions shown previously.

Question 19

release of the orthophosphate results in __________

Answer 19

entropy increase in the system and is therefore favored

Question 20

How can a thermodynamically unfavorable (endergonic) reaction can be made favorable?

Answer 20

by coupling it to a highly favorable (exergonic) reaction

Question 21

what does the oxidation of nutrients provide?

Answer 21

The oxidation of nutrients such as carbohydrates or fats provides cells with substantial free energy for the synthesis of ATP.

Question 22

How is energy stored once its released when transferring electrons from nutrients?

Answer 22

its stored in the form of a proton gradient across the membrane.

Question 23

whats the driving force for the synthesis of ATP in mitochondria

Answer 23

the proton gradient

Question 24

how does the electron transfer take place?

Answer 24

The electron transfer occurs via a series of linked oxidations and reductions, or “redox” reactions

Question 25

To understand the processes by which metabolic energy is extracted from nutrients, one must understand

Answer 25

how to calculate the free energy available from a redox reaction.

Question 26

A complete redox reaction must show:

Answer 26

one reactant as an electron acceptor, which becomes reduced by gaining electrons,

And another reactant as an electron donor, which becomes oxidized by losing electrons.

Question 27

reductant (or reducing agent)

Answer 27

The electron donor is the reductant (or reducing agent), which becomes oxidized.

Question 28

oxidant (or oxidizing agent),

Answer 28

The electron acceptor is the oxidant (or oxidizing agent), which gets reduced.

Question 29

diffusion is an ________ driven process

Answer 29

entropy

Question 30

whats the indicator of spontaneity?

Answer 30

my nigga gibbs (Free energy)

Question 31

what drives protein folding?

Answer 31

J gibbs (deltaG)

Question 32

are living cells at equilibrium?

Answer 32

na brah

Concentrations of reactants and products are typically far from the equilibrium values (Q doesnt equal Keq).

Question 33

If Q > Keq

Answer 33

then deltaG > 0 (reverse reaction is favorable)

Question 34

If Q = Keq

Answer 34

then deltaG = 0 (at equilibrium)

Question 35

If Q < Keq

Answer 35

then deltaG < 0 (reaction favorable as written)

Question 36

is Homeostasis the same thing as equilibrium?

Answer 36

naw bitch!

Homeostasis must not be confused with equilibrium!

Question 37

homeostasis or the homeostatic condition.

Answer 37

life occurs within relatively narrow ranges of temperature, pH, and concentrations for ions and metabolites, this set of conditions is referred to as homeostasis