Respiration Review Sheet
OBJECTIVES
1. Which of the following statements is true of fermentation? It produces a net gain of ATP.
2.The following statements compare combustion with the aerobic respiration of glucose. . Combustion releases energy from glucose at a more rapid rate than does respiration.
. Combustion releases nearly all energy as heat and light; respiration captures some of the energy in chemical bonds.
. Combustion uses heat to provide activation energy; respiration uses enzymes to lower activation energy. Combustion involves the direct transfer of hydrogen atoms to oxygen respiration uses an indirect transfer of hydrogens.
3. Glycolysis is believed to be one of the most ancient of metabolic processes.. Glycolysis neither uses nor needs O2/ Glycolysis is found in all eukaryotic cells. /The enzymes of glycolysis are found in the cytosol rather than in a membrane-bound organelle/Bacteria, the most primitive of cells, make extensive use of glycolysis.
4. the following statements are about lactate fermentation
. Lactate fermentation oxidizes NADH to NAD+ to keep glycolysis functioning. / Lactate fermentation takes place in vigorously exercised muscle cells. /Lactate fermentation can take place under anaerobic conditions. / Lactate fermentation in muscle cells often creates a need for O2 that must be satisfied later.
5.Which kind of metabolic poison would most directly interfere with glycolysis? an agent that closely mimics the structure of glucose but is non- metabolic
6.All of the following statements about glycolysis are true / glycolysis has steps involving oxidation-reduction reactions. / the enzymes of glycolysis are located in the cytosol of the cell./ glycolysis can operate in the complete absence of O2. / glycolysis makes ATP exclusively through substrate-level phosphorylations.
7 the following statements are about NAD+ / NAD+ is reduced to NADH during both glycolysis and the Krebs cycle. / NAD+ is reduced by the action of dehydrogenases./. NAD+ can receive electrons for use in oxidative phosphorylation. / In the absence of NAD+, glycolysis cannot function.
8.Which metabolic process is most closely associated with intracellular membranes? oxidative phosphorylation
9.Pyruvate is the last product of glycolysis. Which statement below is TRUE? There is less energy in two molecules of pyruvate that in one molecule of glucose.
10.During oxidative phosphorylation, H2O is formed. Where do the oxygen atoms in the H2O come from? molecular oxygen
11.What does chemiosmosis involve? A proton-motive force that drives the synthesis of ATP.
12.Muscle cells in oxygen deprivation convert pyruvate to lactate and in this step gainNAD+
13.Phosphofructokinase is an important control enzyme. It is inhibited by ATP. It is activated by ADP. . It is a coordinator of the processes of glycolysis and the Krebs cycle. It is an allosteric enzyme.
14.Which type of enzyme in cellular respiration is primarily responsible for removing electrons from organic molecules? dehydrogenase
15.Why is it impossible to quantify the amount of ATP derived from each glucose molecule during cellular respiration? The proton gradient is used for many purposes.
16.Assume that a eukaryotic cell has abundant glucose and O2, but needs ATP. The proton gradient in mitochondria of this cell will be generated by the electron transport chain and used primarily for ATP synthesis
17.Which process in eukaryotic cells will normally proceed whether O2 is present or absent? glycolysis
18.The direct energy source that drives ATP synthesis during respiratory oxidative phosphorylation is
the difference in H+ proton concentrations on opposite sides of the inner mitochondrial membrane.
19.A fatty acid is partially oxidized to form 10 molecules of acetyl CoA. Starting with these 10 molecules, how many molecules of ATP will be made directly by the Krebs cycle only? 10
20.The primary function of the mitochondrion is the production of ATP. To carry out this function, the mitochondrion must have all of the following /. the membrane-bound electron transport chain. / proton pumps embedded in the inner membrane. / enzymes for the Krebs cycle. /mitochondrial ATP synthase.
21.A major function of the mitochondrial inner membrane is the conversion of energy from electrons to the stored energy of the phosphate bond in ATP. To accomplish this function, this membrane must have all of the following features / proteins to accept electrons from NADH. / integral, transverse ATP synthase./. proton pumps embedded in the membrane./ the electron transport chain of proteins.
22.Fermentation is not as energy productive as respiration because NAD+ is regenerated by alcohol or lactate production, without the high energy electrons passing through the electron transport chain.
23.The oxygen consumed during cellular respiration is directly involved in accepting electrons at the end of the electron transport chain.
24.The ATP made during fermentation is generated by substrate-level phosphorylation
25.All of the following substances are produced in a muscle cell under anaerobic conditions / ATP. / pyruvate. / lactate. /NADH.
26.In addition to ATP, what are the end products of glycolysis? pyruvate and NADH
27.The Krebs cycle energizes molecules that then transfer energy to the electron transport system. What are they? FADH2 and NADH
28. Catabolism of proteins, lipids, and carbohydrates can result in a 2-carbon molecule which enters the Krebs cycle. What is the molecule? . acetyl acids
29.In chemiosmotic phosphorylation, what is the most direct source of energy that is used to convert ADP + Pi to ATP? energy released from diffusion of protons through ATP synthase
30.Suppose a yeast cell uses 10 moles of glucose for energy production. No oxygen is available. What will be the net yield of ATP in moles? 20
31.How many carbon atoms does each acetyl CoA feed into the Krebs cycle? 2
Answer the following question(s), based on the stages of glucose oxidation listed below.
1. stage I: glycolysis
2. stage II: oxidation of pyruvate to acetyl CoA
3. stage III: Krebs cycle
4. stage IV: oxidative phosphorylation (chemiosmosis)
32.Which one of the stages produces the most ATP when glucose is completely oxidized to carbon dioxide and water? 4
33.Which one of the stages occurs whether or not oxygen is present? 1 34.Which one of the stages occurs in the cytoplasm of the cell?1
35.Carbon dioxide is produced during which stage(s)? stages II and III
36.Which of the following intermediary metabolites enters the Kreb cycle and is formed, in part, by the removal of CO2 from a molecule of pyruvate? . acetyl CoA
37.When hydrogen ions are pumped from the mitochondrial matrix, across the inner membrane, and into the intermembrane space, the result is . the creation of a proton gradient.
38.Carbon skeletons to be broken down during cellular respiration can be obtained from polysaccharide, proteins, and lipids.
39.The approximate number of ATP molecules formed in the mitochondrion for each glucose entering respiration is from 36 to 40
40.Where is ATP synthase located in the mitochondrion? . F1 particle of inner membrane
41.The first step of glycolysis, in which glucose is split at a cost of 2 ATP, results in the formation of two 3-carbon molecules of PGAL.
42.Most biological molecules enter the aerobic respiration pathway at the same point. What is that point?
acetyl CoA
43. Each time a molecule of glucose is completely respired, how many oxygen (O2) molecules are required? 6