BIOCHEM CH.3 PART 1

Question 1

What is the first law of thermo?

Answer 1

Energy of the universe is constant; cannot be created or destroyed

Question 2

What is another term used to explain the first law of thermo?

Answer 2

Law of conservation of energy

Question 3

What is the second law of thermo?

Answer 3

Universe tends to increase towards entropy

Question 4

What is the symbol for entropy?

Answer 4

S

Question 5

What is the equation for Gibbs free energy?

Answer 5

ΔG = ΔH - TΔS

Question 6

What does ΔH symbolize?

Answer 6

Enthalpy

Question 7

What is the equation of enthalpy?

Answer 7

ΔH = ΔE + PΔV

Question 8

In the enthalpy equation ΔH = ΔE + PΔV what does E represent?

Answer 8

Bond energy of products or reactions in a system

Question 9

In the enthalpy equation ΔH = ΔE + PΔV what does P represent?

Answer 9

Pressure

Question 10

In the enthalpy equation ΔH = ΔE + PΔV what does V represent?

Answer 10

Volume

Question 11

Since all cellular reactions take place in a liquid phase, how is H related to E in a call?

Answer 11

H = E since the change in volume is negligible ΔV= 0 (no change)

Question 12

Based on increasing and decreasing, how does ΔG relate to ΔH? What about entropy (S)?

Answer 12

ΔG increases with increasing ΔH (bond energy)

Decreases with increasing entropy

Question 13

Favorable reactions has a ΔG that is….?

Answer 13

< 0

Question 14

How does ΔG need to be for the reaction to be favorable? Or unfavorable?

Answer 14

ΔG negative, ΔG positive

Question 15

What does it mean when ΔG is negative in a reaction?

Answer 15

Energy to spare

Question 16

Reaction with a negative ΔG are said to be…?

Answer 16

Exergonic

Question 17

Reaction with a positive ΔG are said to be…?

Answer 17

Endergonic

Question 18

Endergonic reactions only occur if energy is….?

Answer 18

Added

Question 19

Reactions with a negative ΔH are said to be…?

Answer 19

Exothermic

Question 20

Reactions with a positive ΔH are said to be…?

Answer 20

Endothermic

Question 21

What do endothermic reactions require, based on ΔH?

Answer 21

An input of heat

Question 22

How is a standard free energy change calculated ΔG°?

Answer 22

With all reactants and products at 1 M concentration

Question 23

What is the denotation of ΔG°’?

Answer 23

1 M concentration for all solutes except H+ and a pH of 7

Question 24

What is the equation of ΔG°’?

Answer 24

ΔG°’ = -RT(In)K’eq

Question 25

ΔG°' = -RT(In)K'eq, please describe each variable?

Answer 25

``` R = gas constant K'eq = ratio of products to reactants at equilibrium ```

Question 26

How do you calculate K'eq?

Answer 26

K'eq = [C]eq[D]eq / [A]eq[B]eq

Question 27

What is the equation for ΔG for a reaction in the body?

Answer 27

ΔG = ΔG°' + RT(In)Q

Question 28

ΔG = ΔG°' + RT(In)Q, what is Q?

Answer 28

Q = [C][D] / [A][B]

Question 29

What is different between Q and K'eq based on the Gibbs free equations?

Answer 29

Q uses the actual concentrations

Question 30

How would we be able to recreate the laboratory standard initial set-up for ΔG = ΔG°' + RT(In)Q?

Answer 30

Q =1 so InQ = 0 and then ΔG = ΔG°'

Question 31

What is the definition of equilibrium?

Answer 31

The point where the rate of reaction forward equals the rate of reaction in the reverse direction

Question 32

What are the two factors that determine whether a reaction will occur spontaneously in the cell?

Answer 32

1. Intrinsic properties of the reactants and products (Keq) | 12. Concentration of reactants and products (RTInQ)

Question 33

What will thermodynamic tell you about a reaction?

Answer 33

Where a system starts and finishes but nothing about the path travelled to get there

Question 34

What is the name of the energy required to produce a transition state?

Answer 34

Activation energy (Ea)

Question 35

What does a catalyst do in chemical kinetics?

Answer 35

Lowers the Ea of a reaction w/o changing the ΔG?

Question 36

How does the catalyst lower the Ea?

Answer 36

Stabilizing the transition state, making it less thermo unfavored

Question 37

How does catalyst affect free Gibbs energy?

Answer 37

They do not affect ΔG

Question 38

What type of energy metabolism are humans?

Answer 38

Chemoheterotrophs

Question 39

What is oxidation? What is reduction?

Answer 39

Oxidation: Loss of electrons Reduction: Gain of electrons

Question 40

What are the three ways to recognize oxidation reactions?

Answer 40

1. Gain of oxygen atoms 2. Loss of hydrogen atoms 3. Loss of electron

Question 41

What are the three ways to recognize reduction reactions?

Answer 41

1. Loss of oxygen atoms 2. Gain of hydrogen atoms 3. Gain of electrons

Question 42

What does redox pair mean?

Answer 42

When one atoms gets reduced, another one must be oxidized

Question 43

What is the way we extract energy from glucose?

Answer 43

Oxidative catabolism

Question 44

What is the Bronsted-lowry acids and bases definition?

Answer 44

Acids are proton DONORS | Bases are proton ACCEPTORS

Question 45

What is the lewis definition of acids and bases?

Answer 45

Lewis acids are electron-pair acceptors | Lewis bases are electron-pair donors

Question 46

What is a conjugate base?

Answer 46

When an acid donates a H+, its remaining structure is called this

Question 47

What is a conjugate acid?

Answer 47

When a base accepts a H+, its remaining structure is called this

Question 48

The strength of an acid (Ka) is related to what?

Answer 48

Directly related to how much the products are favored over the reactants

Question 49

What is Ka?

Answer 49

Acid-ionization (acid-dissociation) constant of the acid (HA)

Question 50

What is Kb?

Answer 50

Base-ionization (base-dissociation) constant

Question 51

What is polyprotic?

Answer 51

More than one proton to donate

Question 52

What is amphoteric?

Answer 52

A substance that can act as either a acid or a base

Question 53

What type of molecules, based on acids and bases, are always amphoteric?

Answer 53

The conjugate base of a weak polyprotic acid

Question 54

What is the equation of pH?

Answer 54

pH = -log[H+]

Question 55

What does the pH formula imply?

Answer 55

{H+] = 10-pH

Question 56

What is the concentration of H+ in pure water and what's its pH?

Answer 56

[H+] = 10^-7, the pH of water is 7

Question 57

What temperature defines a pH at neutral solution?

Answer 57

25 degrees celsius

Question 58

How to calculate the pKa and pKb?

Answer 58

-logKa or -logKb

Question 59

From the pKa value, how do we know the strength of the acid?

Answer 59

Lower pKa value, stronger acid

Question 60

From the pKb value, how do we know the strength of the base?

Answer 60

Lower pKa value, stronger base

Question 61

What is the most important buffer system in our blood plasma?

Answer 61

Bicarbonate buffer system

Question 62

What molecules are included in the bicarbonate buffer system?

Answer 62

Carbonic acid (H2CO3) and its conjugate base (HCO3-)

Question 63

What are the two reactions of the bicarbonate buffer system?

Answer 63

1. H2CO3 -> H+ + HCO3- | 2. CO2 + H2O -> H2CO3

Question 64

What happens when H+ is high due to lactic acid production?

Answer 64

Reaction 1 H2Co3 -> H+ + HCO3 shifts to the left to reduce amount of free H+