Session 8 Flashcards
What is the fundamental biochemical reason for us to breathe?
A. To buffer our blood to maintain a pH homeostasis
B. To inflate our lungs
C. To oxidize fuels with O2 to produce ATP
D. To purge CO2
C. To oxidize fuels with O2 to produce ATP
Which of the following disease conditions are associated with inadequate bioenergetics?
- Anorexia
- Hyperthyroidism
- Myocardial infarction
- Malnutrition
- Abdominal obesity
- Type 2 diabetes mellitus
- High blood triglyceride levels
A. 1, 3, 5, 7
B. 2,4, 6
C. 6
D. All of them
D. All of them
Why is ATP called the universal energy currency?
ATP is used as the prevalent energy molecule in all 5 domains of life
Why is glucose called the “universal fuel”?
Glucose is used by all cells with or without the presence of oxygen
What is a high-energy bond?
Any chemical bond that releases more than 7 kcal/mol of energy upon hydrolysis
Why is the bond between alpha phosphate group and D-ribose group not a high-energy bond?
Chemical nature; D-ribose is not charged, releases about 3 kcal/mol of energy
Where does the released energy go if this is an isolated reaction? In a biological system?
Dissipates as heat (increase in enthalpy)
Often is coupled with another reaction
What is the first law of thermodynamics?
Conservation of energy; energy can move around but the total energy is constant
What is the second law of thermodynamics?
Universe tends to go toward disorder, total entropy of the system always increases
Which of the following statement about bioenergetics is correct?
A. The first law of thermodynamics states that the universe tends toward an increased order
B. The second law of thermodynamics states that the total energy of a system remains constant
C. The change in enthalpy of a reaction (ΔH) is a measure of the total amount of heat that can be released from changes in the chemical bonds
D. ΔG0’ of a reaction is the standard free-energy change measured at 37°C and a pH at 7.4
E. A high-energy bond is a bond that releases more than 3 kcal/mol of heat when it is hydrolyzed
C. The change in enthalpy of a reaction (ΔH) is a measure of the total amount of heat that can be released from changes in the chemical bonds
Which compound has a higher energy status, G6P or G1P? ΔG0’ is slightly positive
G1P
If you only mix 1 mole of G6P and 1 mole of G1P in a flask and let go for 1 hours, what would you expect to happen? ΔG0’ is slightly positive
No change because there is no enzyme there
If you only mix 1 mole of G6P and 1 mole of G1P in a flask and mix with phosphoglucomutase and let go for 1 hours, what would you expect to happen? ΔG0’ is slightly positive
G6P increases and G1P decreases
Drugs or xenobiotics are metabolized mainly what enzyme at which organelle?
Cytocrome P450s on smooth ER
How is ATP homeostasis achieved in a healthy individual?
Largely through feedback regulation of fuel ingestion, oxidation, usage and storage
