Charging up (L03)

Question 1

What is the First law of thermodynamics?

Answer 1

Energy cannot be created/destroyed

Energy can convert from one form to another

Question 2

What is the Second law of thermodynamics?

Answer 2

Energy may decrease in an organism but the universe’s total entropy increase
ΔS universe = ΔS surroundings + ΔS system

Question 3

What does it mean when ΔG is negative?

Answer 3

System can do work on its own 
Energy is given out 
Exergonic reaction 
Spontaneous reaction 
Thermodynamically favorable

Question 4

What does it mean when ΔG is positive?

Answer 4

System cannot do work on its own, needs to be forced by the external environment 
Energy is taken in
Endergonic reaction 
Non-spontaneous reaction 
Thermodynamically unfavorable

Question 5

What does ΔH, ΔG and ΔS represent?

Answer 5

ΔH: enthalpy, heat generated/taken in by the reaction
ΔG: free energy, energy available to do useful work
ΔS: entropy, disorder generated by the reaction

Question 6

What is substrate level phosphorylation?

Answer 6

When the phosphate group is transferred directly to ADP to form a more energetic molecule

Question 7

What is oxidative phosphorylation?

Answer 7

ATP is formed as a result of the transfer of electrons, from NADH/FADH2 to O2 by electron carriers

Question 8

How to calculate the free energy, entropy and enthalpy of a reaction?

Answer 8

ΔG = ΔG products - ΔG reactants 
ΔS = ΔS products - ΔS reactants 
ΔH = ΔH products - ΔH reactants