Bioenergetics

Question 1

What is an oxidizing agent?

Answer 1

a substance that tends to bring about oxidation by being reduced and gaining electrons

Question 2

What is a reducing agent?

Answer 2

a substance that tends to bring about reduction by being oxidized and losing electrons

Question 3

The production of NADH and FADH2 involves what type of reactions?

Answer 3

oxidation-reduction

Question 4

How many ATP will be produced by 1 glucose molecule?

Answer 4

38 ATP

Question 5

Number of acetyl CoA formed from one molecule of glucose is?

Answer 5

2

Question 6

Define Thermodynamics

Answer 6

Thermodynamics is a branch of Physics that deals with energy changes.

Question 7

Define Bioenergetics

Answer 7

The study of the changes in energy during metabolic reactions.

Question 8

_________ is part of thermodynamics.

Answer 8

bioenergetics

Question 9

State the laws of thermodynamics

Answer 9

1. Energy may change form, or transported from one place to another but it cannot be destroyed or created.
2. Any spontaneous chemical or physical change is always accompanied by increase in the disorder of the universe.

Question 10

In the process of transforming energy, how must living organisms affect the universe?

Answer 10

living organisms must increase the entropy of the universe

Question 11

In order to maintain organization within themselves, living systems must be able to?

Answer 11

1. extract useable energy from the surrounding

2. release useless energy (heat) back to the surrounding

Question 12

What is Gibbs free energy?

Answer 12

energy that can do work when temperature and pressure are uniform, as in a living cell

Question 13

What is free-energy change (ΔG)?

Answer 13

a measure of the chemical energy available from a reaction

Question 14

What is the Gibbs-Helmholtz equation?

Answer 14

ΔG = ΔH - TΔS

Question 15

Which part of the Gibbs-Helmholtz equation (ΔG = ΔH - TΔS) predicts whether a reaction is favorable?

Answer 15

ΔG

Question 16

Which part of the Gibbs-Helmholtz equation (ΔG = ΔH - TΔS) approaches zero as reaction proceeds to equilibrium?

Answer 16

ΔG

Question 17

Which part of the Gibbs-Helmholtz equation (ΔG = ΔH - TΔS) is the energy available to do work?

Answer 17

ΔG

Question 18

Which part of the Gibbs-Helmholtz equation (ΔG = ΔH - TΔS) is heat released or absorbed during a reaction?

Answer 18

ΔH

Question 19

Which part of the Gibbs-Helmholtz equation (ΔG = ΔH - TΔS) does not predict whether a reaction is favorable?

Answer 19

ΔH and TΔS

Question 20

Which part of the Gibbs-Helmholtz equation (ΔG = ΔH - TΔS) is change in entropy (a measure of randomness)?

Answer 20

ΔS

Question 21

Which part of the Gibbs-Helmholtz equation (ΔG = ΔH - TΔS) is change in enthalpy?

Answer 21

ΔH

Question 22

What does enthalpy represent?

Answer 22

Represents the heat content of the reacting systems

Question 23

If heat is released during a reaction, i.e. ΔH is _______, then this is an _________ reaction.

Answer 23

negative; exothermic

Question 24

If heat is absorbed during a reaction, i.e. ΔH is _______, then this is an _________ reaction.

Answer 24

positive; endothermic

Question 25

What is entropy?

Answer 25

it is a quantitative expression for the randomness or disorder in the system

Question 26

If entropy decreases in an organism, it [decreases/increases] in the universe.

Answer 26

increases

Question 27

In an [endergonic/exergonic] reaction, ΔG has a negative value.

Answer 27

exergonic

Question 28

In an [endergonic/exergonic] reaction, ΔG has a positive value.

Answer 28

endergonic

Question 29

An [endergonic/exergonic] reaction proceeds with a net release of free energy.

Answer 29

exergonic

Question 30

An [endergonic/exergonic] reaction is spontaneous.

Answer 30

exergonic

Question 31

An [endergonic/exergonic] reaction absorbs free energy from its surroundings.

Answer 31

endergonic

Question 32

An [endergonic/exergonic] reaction is nonspontaneous.

Answer 32

endergonic

Question 33

What is free energy?

Answer 33

Free energy is a measure of a system’s instability, its tendency to change to a more stable state

Question 34

During a spontaneous change, free energy [decreases/increases] and the stability of a system [decreases/increases].

Answer 34

decreases; increases

Question 35

______ is a state of maximum stability.

Answer 35

equilibrium

Question 36

A process is spontaneous and can perform work only when it is moving toward?

Answer 36

equilibrium

Question 37

Define equilibrium

Answer 37

the state in which the chemical activities or concentrations of the reactants and products have no net change over time

Question 38

What results when the forward chemical process proceeds at the same rate as their reverse reaction?

Answer 38

equilibrium

Question 39

What is the formula of ΔG0?

Answer 39

∆G⁰ = - RT ln Keq

Question 40

[ΔG/ΔG0] is the actual free energy change

Answer 40

ΔG

Question 41

[ΔG/ΔG0] is the standard Free Energy change of a reaction

Answer 41

ΔG0

Question 42

Describe this: ΔG < 0

Answer 42

spontaneous reaction

Question 43

Describe this: ΔG > 0

Answer 43

needs energy

Question 44

Describe this: ΔG = 0

Answer 44

equilibrium

Question 45

What is the gas constant (R)?

Answer 45

Gas constant = 8.315

Question 46

1 calorie is equal to how many joules?

Answer 46

4.184 J