Bioenergetics LO Flashcards Preview

M2M Biochemistry and molecular biology > Bioenergetics LO > Flashcards

Flashcards in Bioenergetics LO Deck (34):
1

Define Entropy

randomness associated with a given system

2

Define enthalpy

measure of heat content (thermodynamic potential) of a system

3

Define free energy

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

4

Define high energy compounds

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

5

Define oxidation-reduction reaction

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

6

What is the 1st law of thermodynamics?

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

7

what is the 2nd law of thermodynamics?

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

Describe kinetic energy

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

9

Describe potential energy

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

10

describe radiant energy

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

11

describe thermal energy

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

12

describe mechanical energy

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

13

describe electric energy

energy movement of charged particles down gradients of electrical potential

14

describe chemical energy

energy stored in chemical bonds

15

how do you calculate deltaG?

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

16

how to you calculate deltaGprime?

- RT ln (Keq)

17

how do you calculate deltaG?

∆H – (T * ∆S )

18

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

spontaneous

19

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

not spontaneous

20

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

at equilibrium

21

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

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

22

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

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

23

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

increases the spontaneity of the reaction (decreases ∆G)

24

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

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

25

how do you calculate ∆E for a reaction?

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

26

when is Eo of a molecule high?

when the molecule is more electronegative

27

when is Eo of a molecule more negative?

when the molecule is more electropositive

28

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

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

29

what does coupling of a reaction mean?

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

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

thioester bonds C-S

31

what is the high energy bond in ATP?

phosphoanhydride bonds (P-O-P)

32

what is the high energy bond in phosphocreatine?

P-N

33

what is the high energy bond in phosphoenolpyruvate?

C-O-P

34

What is considered high yield currency in bioenergetics?

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