Chapter 3: Energy, Catalysis and Biosynthesis

Question 1

First Law of Thermodynamics

Answer 1

Energy cannot be created nor destroyed, but it can be converted from one form to another

Question 2

Second Law of Thermodynamics

Answer 2

entropy(dispersal of energy) increases whenever anything happens

Question 3

Since cells use a tremendous amount of energy to create and maintain order how does the 2nd law still apply?

Answer 3

entropy in the surroundings increases; largely due to release of heat.

Question 4

Where do cells get the energy required to create and maintain order?

Answer 4

Light (electromagnetic energy)
Food(chemical bond energy)

Question 5

How do cells obtain energy

Answer 5

oxidation of organic molecules

Question 6

In the presence of oxygen, what is the most stable form of C

Answer 6

CO2

Question 7

In the presence of oxygen, what is the most stable form of H?

Answer 7

H2O

Question 8

Oxidation(dehydrogenation)

Answer 8

Loss of electrons

Question 9

reduction(hydrogenation)

Answer 9

gain of electrons

Question 10

Sugars versus fats energy amount

Answer 10

fats>sugars

Question 11

G

Answer 11

free energy (kcal/mole)

Question 12

Energetically favorable reactions change in free energy

Answer 12

negative

Question 13

triangle Gibbs 0

Answer 13

energy stored in chemical bonds

Question 14

change in free energy

Answer 14

^G = ^G°+ RT ln [products]/[reactants]
^= triangles

Question 15

^Gº standard conditions

Answer 15

25C
1 atm pressure
1M concentration
pH7

Question 16

RT Equation

Answer 16

RT = gas constant ×absolute temp = 0.616 @ 37ºC

Question 17

Meaning of positive G

Answer 17

create order and are unfavorable

Question 18

If product is great than reactions what does the natural log equal

Answer 18

positive

Question 19

Relationship between ^G0 and Keq

Answer 19

0 = ^G = ^Gº + RT ln Keq
^Gº = -RT ln Keq
= -0.616 ln Keq

Question 20

Sequential “siphon” coupled reaction

Answer 20

the reactions meets an equilibrium point

Question 21

Activated Carrier

Answer 21

one reaction produces the reaction for another reaction

Question 22

Activated Carriers

Answer 22

ATP
NADH and NADPH

Question 23

Oxidized Electron Carrier

Answer 23

NADP+

Question 24

Reduced Electron Carrier

Answer 24

NADPH

Question 25

How do cells harness some of the energy for chemical work?

Answer 25

they breakdown the molecules through many steps

Question 26

How do enzymes increase the rate of reactions?

Answer 26

by reducing the activation energy

Question 27

At equilibrium if there are more reactants than products if the ^G0 positive or negative?

Answer 27

positive

Question 28

At equilibrium if the products are more abundant then the reactants if the ^G0 negative or positive?

Answer 28

negative

Question 29

^G0 effect as a reaction moves to equilibrium

Answer 29

stays the same

Question 30

Oxidation of molecules occurs during what process

Answer 30

catabolism