Understand aerobic respiration
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AP Biology › Understand aerobic respiration
Eukaryotes are capable of producing ATP with or without oxygen. In comparison, prokaryotes __________.
None of these; it depends on the type of prokaryote.
only produce ATP when oxygen is present
only produce ATP when oxygen is not present
are also capable of producing ATP with and without oxygen
do not produce ATP
Explanation
One way to divide prokaryotes is into aerobes and anaerobes. Aerobes are organisms that can survive and grow in the presence of oxygen while anaerobes did not require oxygen for survival and growth. All aerobes can produce ATP with or without oxygen (though they may need oxygen for survival. However some anaerobes are harmed by the presence of oxygen (obligate anaerobes). These anaerobes can produce ATP through glycolysis or anaerobic respiration, where another molecule besides oxygen is used as the final electron acceptor for the electron transport chain.
Anaerobic respiration occurs when?
In the presence of
In the absence of
In the presence of
In the absence of
Explanation
If no oxygen is available, anaerobic respiration will occur. This can either be lactic acid fermentation, or alcoholic fermentation. In alcoholic or lactic acid fermentation, the pyruvate are decarboxylated and ultimately used to produce either ethanol or lactic acid, and regenerate NAD+ which will be reused for another cycle of glycolysis (2 ATP are produced for each round of glycolysis).
Oxygen is necessary for aerobic respiration, because __________.
it is the final electron acceptor in the electron transport chain
it donates its electrons to the electron transport chain
it is necessary in order for ATP synthase to work properly
it establishes the proton gradient
Explanation
Oxygen is the final electron acceptor in aerobic respiration. It becomes water upon being reduced by the accepted electrons, which explains why water is one of the products of respiration. Without the presence of oxygen, electrons would remain trapped and bound in the final step of the electron transport chain, preventing further reaction.
NADH and FADH2 are necessary to donate electrons to the electron transport chain.
Where does anaerobic respiration occur in a cell?
Mitochondrial matrix
Inner mitochondrial membrane
Cytosol
Chloroplast
Explanation
In the absence of oxygen, pyruvate produced during glycolysis will be used for either lactic acid or alcoholic fermentation, producing lactic acid or ethanol (as waste products) and regenerating NAD+ to be used for another cycle of glycolysis. This fermentation occurs in the cytosol of the cell.
Which of the following chemical equations represents the net chemical reaction of aerobic cellular respiration?
None of these
Explanation
Aerobic cellular respiration is the process of breaking down glucose 
In the process of cellular respiration, if no oxygen is available, what is the fate of the pyruvate molecules produced during glycolysis?
Used to produce oxygen
Used for lactic acid or alcoholic fermentation
Used to produce more glucose
Used to produce protons to increase the proton gradient
Explanation
If no oxygen is available, anaerobic respiration will occur. This can either be lactic acid fermentation, or alcoholic fermentation. In alcoholic or lactic acid fermentation, the pyruvate are decarboxylated and ultimately used to produce either ethanol or lactic acid, and regenerate NAD+ which will be reused for another cycle of glycolysis (2 ATP are produced for each round of glycolysis).