Bioenergetics Flashcards
A reaction with a large positive change in free energy is
Extremely unfavorable
An unfavorable reaction has an equilibrium constant between
Zero and 1
An endothermic reaction has a
Positive change in enthalpy, or +∆H
How is the change in free energy for exergonic reactions?
Negative, -∆G
A negative change in free energy (-∆G) represents a
Spontaneous reaction
Spontaneous reactions have equilibrium constants that are
Greater than 1
ATP hydrolysis refers to the reaction that
Cleaves the phosphoanhydride bond that results in a phosphate molecule and ADP as products
ATP hydrolysis involves the hydrolysis of the
Phosphoanhydride bond linking the gamma phosphate to the beta phosphate
A spontaneous reaction always
Decreases free energy ∆G of the system
The standard reduction potential is a measure of the
Tendency of a chemical species to be reduced
How many Pi are in ADP?
2
How many Pi are in ATP?
1
The free energy stored by ADP is
Positive and greater that the free energy stored by AMP
One would expect ATP hydrolysis to be non-spontaneous when
ATP concentration is very far below equilibrium concentration and ADP concentration is very far above equilibrium concentration
Spontaneous reactions have products that have a
Lower energy compared to reactants
Cellular respiration is a redox reaction involving
Glucose and Oxygen
The products of cellular respiration are
- Water
- CO2
- Heat
Glucose is oxidized to what molecule during aerobic cellular respiration?
CO2
Oxygen is reduced to what molecule during aerobic cellular respiration?
Water
What is the ultimate source of electrons for aerobic cellular respiration?
Glucose
What is the final electron acceptor in aerobic cellular respiration?
Oxygen
Aerobic cellular respiration results in the transfer of electrons from
Glucose to Oxygen
ΔG represents the difference of
Free energy between products and reactants
A negative ΔG means that the
Products have less energy than reactants
∆G is unaffected by
Catalysts
Cellular respiration reactants have
High energy
What kind of reaction is cellular respiration?
Exergonic
Endergonic reactions have a
+∆G
Exergonic reactions have a
-∆G
If an antibiotic works properly, it will
Reduce enzymatic activities in bacteria
What happens to the activation energy of certain bacteria’s chemical reactions if an antibiotic works properly?
The energy increases
A competitive inhibitor has an affinity for
Enzyme active sites
The absence of Oxygen in the ETC would reduce the
Overall free energy released
What kind of reaction is the ETC overall?
Exergonic
Muscle contraction depends on
Energy release for ATP breakdown
ATP breakdown occurs via
Hydrolysis
