Chapter 9 reading quiz
In the absence of oxygen, yeast cells can obtain energy by fermentation, which results in the net production of which of the following sets of molecules?
ATP, CO2, and ethanol
Which of the following molecules is the lowest-energy donor of electrons to the electron transport chain?
FADH2
Which of the following statements best describes the electron transport chain?
It consists of a series of redox reactions.
Which of the following statements best describes the primary role played by oxygen in cellular respiration?
It serves as the final acceptor for electrons from the electron transport chain.
Energy released from the electron transport chain is used to pump H+ ions into which location in eukaryotic cells?
mitochondrial intermembrane space
Which of the following products result from the oxidation of pyruvate to acetyl-CoA?
NADH and CO2
If pyruvate oxidation is blocked, what is the most likely effect on the levels of oxaloacetate and citrate in the citric acid cycle shown in the accompanying figure?
Oxaloacetate will accumulate and citrate will decrease. Submit
In cellular respiration, a series of molecules forming an electron transport chain alternately accepts and then donates electrons. What is the advantage of such an electron transport chain?
The advantage of an electron transport chain is that a small amount of energy is released with the transfer of an electron between each pair of intermediates.
Identify all correct statements about the basic function of fermentation.
The basic function of fermentation is the regeneration of NAD+, which allows continued ATP production by glycolysis.
Which of the following statements accurately describes the function of a metabolic pathway involved in cellular respiration?
The function of glycolysis is to begin catabolism by breaking glucose into two molecules of pyruvate, with a net yield of two ATP. Submit
Which of the following types of metabolic poison would most directly interfere with glycosides?
an agent that closely mimics the structure of glucose but is not metabolized
What is the oxidizing agent in the following reaction? Pyruvate + NADH + H+ S Lactate + NAD+
pyruvate
Which of the following best predicts the effect of removal of oxygen from a facultative anaerobic organism's environment?
glucose consumption increases, while the growth rate decreases
Under which conditions will plant cell mitochondria actively oxidize pyruvate and carry out oxidative phosphorylation?
in all cells, with or without light Submit
Which of the following reactions produces the majority of the CO2 released by the complete oxidation of glucose?
the citric acid cycle Submit
When a cell is deprived of oxygen, which of the following processes will be inhibited first?
the electron transport chain Submit
Which of the following events takes place in the electron transport chain?
the harnessing of energy from redox reactions to generate a proton gradient Submit
The enzyme phosphofructokinase (PFK) catalyzes a key step in glycolysis and is inhibited by high levels of which of the following molecules?
ATP and citrate
What types of cells carry out ATP synthesis by chemiosmosis?
all respiring cells, both prokaryotic and eukaryotic, using either oxygen or other electron acceptors
Which of the summary statements below describes the results of the following reaction? C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy
C6H12O6 is oxidized and O2 is reduced.
Select the correct statement about cellular respiration?
Cellular respiration and breathing differ in that cellular respiration is at the cellular level, whereas breathing is at the organismal level.
Depletion of which of the following molecules from the mitochondria will most directly inhibit the citric acid cycle?
NAD+
which of the following statements best describes what happens to a molecule of NAD+ when it gains a hydrogen atom?
NAD+ becomes reduced
Which of the following statements about the citric acid cycle is correct?
The last reaction in the citric acid cycle produces a product that is a substrate for the first reaction of the citric acid cycle. Submit
When electrons flow along the electron transport chains of mitochondria, which of the following changes occurs?
The pHpH of the matrix increases.
Which one of the following statements about the redox reactions of the electron transport chain is correct?
The redox reactions of the electron transport chain are directly coupled to the movement of protons across a membrane.
Which of the following statements best explains why carbohydrates and fats may be considered high energy foods?
They contain many electrons associated with hydrogen atoms
Exposing inner mitochondrial membranes to ultrasonic vibrations will fragment the membranes and pieces will reseal "inside out" to form small vesicles. The fact that these vesicles can transfer electrons from NADH to oxygen and synthesize ATP suggests that which of the following components must be present?
all of the electron transport system and ATP synthase
