oxidative phosphorylation
For each glucose that enters glycolysis, _____ acetyl CoA enter the citric acid cycle.
2
Under anaerobic conditions (a lack of oxygen), the conversion of pyruvate to acetyl CoA stops. Which of these statements is the correct explanation for this observation? A - Oxygen is required to convert glucose to pyruvate in glycolysis. Without oxygen, no pyruvate can be made. B - In the absence of oxygen, electron transport stops. NADH is no longer converted to NAD+, which is needed for the first three stages of cellular respiration. D - ATP is needed to convert pyruvate to acetyl CoA. Without oxygen, no ATP can be made in oxidative phosphorylation. E - Oxygen is an input to acetyl CoA formation.
B - In the absence of oxygen, electron transport stops. NADH is no longer converted to NAD+, which is needed for the first three stages of cellular respiration.
The electrons stripped from glucose in cellular respiration end up in which compound? A - oxygen B - water C - NADH D - ATP E - carbon dioxide
B - water At the end of the electron transport chain, the electrons and hydrogen atoms are added to oxygen, forming water.
Which of the following statements about the chemiosmotic synthesis of ATP is correct? A - The energy for production of ATP from ADP comes directly from a gradient of electrons across the inner mitochondrial membrane. B - Oxygen participates directly in the reaction that makes ATP from ADP and P. C - The chemiosmotic synthesis of ATP requires that the electron transport in the inner mitochondrial membrane be coupled to proton transport across the same membrane. D - The chemiosmotic synthesis of ATP occurs only in eukaryotic cells, because it occurs in mitochondria. E - Chemiosmotic ATP synthesis requires oxygen.
C - The chemiosmotic synthesis of ATP requires that the electron transport in the inner mitochondrial membrane be coupled to proton transport across the same membrane.
The proximate (immediate) source of energy for oxidative phosphorylation is _____. A - NADH and FADH2 B - substrate-level phosphorylation C - kinetic energy that is released as hydrogen ions diffuse down their concentration gradient D - ATP E - ATP synthase
C - kinetic energy that is released as hydrogen ions diffuse down their concentration gradient
Which one of the following statements about the redox reactions of the electron transport chain is correct? A - The redox reactions of the electron transport chain are directly coupled with the synthesis of ATP. B - The electron transport chain takes electrons from water and gives them to oxygen. C - The oxidation of NADH is directly coupled to the reduction of oxygen to water. D - The redox reactions of the electron transport chain are directly coupled to the movement of protons across a membrane. E - NADH gains electrons in the initial reaction of the electron transport chain.
D - The redox reactions of the electron transport chain are directly coupled to the movement of protons across a membrane.
The primary role of oxygen in cellular respiration is to... A - combine with lactate, forming pyruvate. B - yield energy in the form of ATP as it is passed down the respiratory chain. C - catalyze the reactions of glycolysis. D - act as an acceptor for electrons and hydrogen, forming water. E - combine with carbon, forming CO2.
D - act as an acceptor for electrons and hydrogen, forming water.
ATP synthases are found in the prokaryotic plasma membrane and in mitochondria and chloroplasts. What does this suggest about the evolutionary relationship of these eukaryotic organelles to prokaryotes? It suggests that the organelles, mitochondria and chloroplasts, arose from a(n) --- relationship with bacteria early in evolutionary time. If the ATP synthases arose independently for each cases, i.e., through convergent evolution, you would expect very --- amino acid sequences.
It suggests that the organelles, mitochondria and chloroplasts, arose from a(n) ENDOSYMBIOTIC relationship with bacteria early in evolutionary time. If the ATP synthases arose independently for each cases, i.e., through convergent evolution, you would expect very DIFFERENT amino acid sequences.
