Cellular Energetics Flashcards
What is the most important molecule for capturing and transferring free energy in biological systems?
Adenosine triphosphate (ATP)
ATP is considered the universal ‘currency’ of chemical energy in all types of organisms.
What type of bond in ATP is hydrolyzed to release energy?
Phosphoanhydride bond
The terminal ‘high-energy’ bond is responsible for powering energetically unfavorable processes.
List three examples of processes powered by ATP hydrolysis.
Synthesis of proteins from amino acids
Transport of molecules against a concentration gradient
Contraction of muscle
What is the reaction for the synthesis of ATP from ADP and inorganic phosphate?
Pi 2- + H+ + ADP3- → ATP4- + H2O
What are the two main processes that produce energy for ATP synthesis?
Aerobic oxidation
Photosynthesis
What is chemiosmosis?
A mechanism used by bacteria, mitochondria, and chloroplasts to generate ATP from ADP and Pi
It involves a proton (H+) concentration gradient and an electric potential across the membrane
What is the proton-motive force?
A combination of a proton concentration gradient and an electric potential across the membrane
This force drives ATP synthesis.
What is the F0F1 complex commonly referred to
ATP synthase
How many molecules of CO2 are produced from the complete aerobic oxidation of one molecule of glucose?
6 molecules of CO2
What is the overall reaction for the complete aerobic oxidation of glucose?
C6H12O6 +6 O2 +30 Pi 2- +30 ADP3- +30 H+ → 6 CO2 +30 ATP4- +36 H2O
What do NADH and FADH2 donate in the electron transport chain?
Electrons
What is the result of electron transfer from NADH to O2?
Formation of water (H2O)
The reaction is: 2 e- + 2 H+ + 1/2 O2 → H2O.
What are the two main events that occur in the respiratory chain?
Electron transfer
Proton transport acrost the mitochondrial membrane
What is required for the synthesis of ATP by the F0F1 complex?
A pH gradient across the membrane
Fill in the blank: Mitochondria, chloroplasts, and bacteria utilize essentially the same kind of membrane protein, the ______, to synthesize ATP.
F0F1 complex
Fill in the blank: Electron transfer from NADH or FADH2 to O2 is coupled to ______ across the mitochondrial membrane.
proton transport
Describe the binding-change mechanism of ATP synthesis from ADP and Pi.
O state: binds ATP poorly, ADP and Pi weakly
L state: binds ADP and Pi more strongly
T state: binds ADP and Pi tightly, forming ATP
True or False: The F0F1 complex is involved only in aerobic respiration.
False
It is also involved in photosynthesis.
What is the function of the F0F1 complex in cellular energetics?
Synthesize ATP
