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M2M Biochemistry and molecular biology > Bioenergetics LO > Flashcards

Flashcards in Bioenergetics LO Deck (34)
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1
Q

Define Entropy

A

randomness associated with a given system

2
Q

Define enthalpy

A

measure of heat content (thermodynamic potential) of a system

3
Q

Define free energy

A

the amount of thermodynamic energy in a system that can be converted into work at a given temperature and pressure

4
Q

Define high energy compounds

A

compounds with bonds that release greater than 7 kcal/mol of energy when broken (deltaG= -7; chemical energy greater than 7 kcal/mol)

5
Q

Define oxidation-reduction reaction

A

a chemical reaction involving the transfer of electrons away from oxidized compounds to reduced compounds

6
Q

What is the 1st law of thermodynamics?

A

energy conservation (energy cannot be created or destroyed, only converted to other forms)

7
Q

what is the 2nd law of thermodynamics?

A

the entropy of the universe is constantly increasing (any given set of reactions that occur simultaneously in a system must increase the overall entropy)

8
Q

Describe kinetic energy

A

energy of motion (radiant, thermal, mechanical, electric)

9
Q

Describe potential energy

A

energy stored within a system due to configuration or position, can be converted to kinetic energy to perform work

10
Q

describe radiant energy

A

carried in photons from sun, the ultimate source of all forms of energy in living systems

11
Q

describe thermal energy

A

kinetic energy of molecules (molecular translation, rotation, vibration, e- spin, translation, and nuclear spin) proteins function at an optimal thermal energy

12
Q

describe mechanical energy

A

potential and kinetic energy within a mechanical system, discussed within the confines of cellular movement of charge particles down gradients of electric potential

13
Q

describe electric energy

A

energy movement of charged particles down gradients of electrical potential

14
Q

describe chemical energy

A

energy stored in chemical bonds

15
Q

how do you calculate deltaG?

A

∆G0 + (RT * ln [PRODUCTS]/[REACTANTS])

16
Q

how to you calculate deltaGprime?

A
  • RT ln (Keq)
17
Q

how do you calculate deltaG?

A

∆H – (T * ∆S )

18
Q

what is the spontaneity of this reaction? ∆G<0

A

spontaneous

19
Q

what is the spontaneity of this reaction? ∆G>0

A

not spontaneous

20
Q

what is the spontaneity of this reaction? ∆G=0

A

at equilibrium

21
Q

what does positive entropy do to change the spontaneity of a reaction? (hint use ∆G = ∆H – T ∆S)

A

increases the spontaneity of the reaction (decreases ∆G)(-∆H = exothermic)

22
Q

what does a negative entropy do to change the spontaneity of a reaction? (hint use ∆G = ∆H – T ∆S)

A

decreases the spontaneity of the reaction (increases ∆G) (∆H = endothermic)

23
Q

what does a negative enthalpy do to change the spontaneity of a reaction? (hint use ∆G = ∆H – T ∆S)

A

increases the spontaneity of the reaction (decreases ∆G)

24
Q

what does a positive enthalpy do to change the spontaneity of a reaction? (hint use ∆G = ∆H – T ∆S)

A

decreases the spontaneity of the reaction (increases ∆G)(+∆S = increased entropy)

25
Q

how do you calculate ∆E for a reaction?

A

subtract the Eo of the electron donor from the Eo of the electron acceptor.

26
Q

when is Eo of a molecule high?

A

when the molecule is more electronegative

27
Q

when is Eo of a molecule more negative?

A

when the molecule is more electropositive

28
Q

what equation do you use to calculate gibbs free energy using redox potential?

A
∆G = -nF∆E
n = #of electrons transferred
F = Faraday's constant
∆E = difference in reduction potential in volts
29
Q

what does coupling of a reaction mean?

A

the SUM of gibbs free energy of 2 or more reactions to determine the spontaneity of the reaction (ex. +∆G can be spontaneous if paired with -∆G of greater absolute value)

30
Q

What is the high energy bond in acetyl Co-A?

A

thioester bonds C-S

31
Q

what is the high energy bond in ATP?

A

phosphoanhydride bonds (P-O-P)

32
Q

what is the high energy bond in phosphocreatine?

A

P-N

33
Q

what is the high energy bond in phosphoenolpyruvate?

A

C-O-P

34
Q

What is considered high yield currency in bioenergetics?

A

bonds that are easy to use, break, and reform.