 |
| 1 | |
Reactions that release energy are usually called |
| | A) | anabolic reactions. |
| | B) | metabolic reactions. |
| | C) | catabolic reactions. |
|
|
|
| 2 | |
Which of the following molecules is the final electron acceptor for all fuel molecules that are completely broken down to carbon dioxide and water within the mitochondria of an animal cell? |
| | A) | glucose |
| | B) | fatty acid |
| | C) | oxygen |
| | D) | amino acid |
|
|
|
| 3 | |
Which of these is not a final product of aerobic cell respiration? |
| | A) | carbon dioxide |
| | B) | water |
| | C) | oxygen |
| | D) | energy (ATP) |
|
|
|
| 4 | |
In the cell's respiration of glucose forming two molecules of pyruvic acid, four atoms of ____ are removed. |
| | A) | carbon |
| | B) | hydrogen |
| | C) | oxygen |
| | D) | carbon dioxide |
|
|
|
| 5 | |
Which of the following statements about glycolysis is false? |
| | A) | It results in the formation of two molecules of pyruvic acid. |
| | B) | It results in the net gain of four ATP molecules. |
| | C) | It can occur with or without oxygen present. |
| | D) | It is an exergonic reaction. |
|
|
|
| 6 | |
As a result of anaerobic respiration in humans, glucose is converted to |
| | A) | pyruvic acid. |
| | B) | lactic acid. |
| | C) | citric acid. |
| | D) | acetyl CoA. |
|
|
|
| 7 | |
The organ most responsible for extracting and converting lactic acid to pyruvic acid, and which ultimately reforms and releases free glucose via the Cori cycle into the bloodstream, is the |
| | A) | liver. |
| | B) | brain. |
| | C) | cardiac muscle. |
| | D) | skeletal muscle. |
|
|
|
| 8 | |
The conversion of noncarbohydrate molecules into glucose, is an example of |
| | A) | glycogenolysis. |
| | B) | glycogenesis. |
| | C) | gluconeogenesis. |
| | D) | glycolysis. |
|
|
|
| 9 | |
Which of the following tissues can survive longest in the absence of adequate oxygen (anaerobic conditions) by deriving energy from the anaerobic respiration of glucose molecules? |
| | A) | the brain |
| | B) | cardiac muscle |
| | C) | the kidneys |
| | D) | skeletal muscle |
|
|
|
| 10 | |
Glycolysis is inhibited by high concentrations of |
| | A) | glucose. |
| | B) | oxygen. |
| | C) | ADP. |
| | D) | ATP. |
|
|
|
| 11 | |
In addition to energy (ATP), what is (are) the final product(s) of aerobic respiration? |
| | A) | O2 and CO2 |
| | B) | CO2 and H2O |
| | C) | O2 and H2O |
| | D) | CO2 only |
|
|
|
| 12 | |
In aerobic respiration, about ____ percent of the chemical bond energy that is released from glucose is captured in the high-energy bonds of ATP molecules. |
| | A) | 40% |
| | B) | 50% |
| | C) | 60% |
| | D) | 70% |
|
|
|
| 13 | |
Anaerobic respiration |
| | A) | is the primary metabolic pathway of cardiac muscle. |
| | B) | is induced by ischemia. |
| | C) | produces water and carbon dioxide as products. |
| | D) | produces a maximum of 30 ATP. |
|
|
|
| 14 | |
Which of the following processes does not occur as an acetic acid subunit enters the mitochondrion and progresses around one complete circuit of the Krebs cycle? |
| | A) | One GTP molecule is converted to one ATP molecule. |
| | B) | Three NAD molecules are reduced by the addition of electrons (H's). |
| | C) | One molecule of oxygen (O2) is combined with carbon to form carbon dioxide (CO2). |
| | D) | One molecule of FAD is reduced by the addition of high energy electrons (H's). |
|
|
|
| 15 | |
Which of the following molecules is not an integral part of the electron-transport chain? |
| | A) | iron-containing cytochrome pigments |
| | B) | flavin mononucleotide (FMN) derived from the vitamin, riboflavin |
| | C) | coenzyme Q |
| | D) | coenzyme A |
|
|
|
| 16 | |
All of the following are formed as a result of the electron-transport chain except |
| | A) | carbon dioxide. |
| | B) | oxidized NAD. |
| | C) | water. |
| | D) | ATP. |
|
|
|
| 17 | |
The chemiosmotic theory describes how the electron-transport system produces ATP using active proton pumps located within the |
| | A) | nuclear membrane. |
| | B) | plasma (cellular) membrane. |
| | C) | mitochondrial inner membrane. |
| | D) | mitochondrial outer membrane. |
|
|
|
| 18 | |
The lollipop-like structures known as respiratory assemblies that can be seen under very high magnification with an electron microscope, are critically important in what process? |
| | A) | glycolysis |
| | B) | Krebs cycle |
| | C) | oxidative phosphorylation |
| | D) | gluconeogenesis |
|
|
|
| 19 | |
As outlined in table 5.2, the latest estimate of the total number of net ATP molecules that can be maximally generated by the complete aerobic respiration of glucose in aerobic respiration is |
| | A) | twelve. |
| | B) | twenty-four. |
| | C) | thirty. |
| | D) | thirty-eight. |
|
|
|
| 20 | |
The conversion of glycogen to glucose-1-phosphate is the first step in |
| | A) | glycolysis. |
| | B) | gluconeogenesis. |
| | C) | glycogenolysis. |
| | D) | glycogenesis. |
|
|
|
| 21 | |
The enzyme found only in the liver that removes phosphate groups and can, thus, release free glucose for distribution around the body by the blood is |
| | A) | glycogen synthetase. |
| | B) | glucose-6-phosphatase. |
| | C) | glycogen phosphorylase. |
| | D) | glucose isomerase. |
|
|
|
| 22 | |
Glucose molecules entering skeletal muscle fibers are "trapped" when converted to |
| | A) | pyruvic acid. |
| | B) | glucose 1-phosphate. |
| | C) | glucose 6-phosphate. |
| | D) | glycogen. |
|
|
|
| 23 | |
Acetyl CoA is an important metabolic intersection leading to the formation of all of the following substances except |
| | A) | prostaglandin molecules. |
| | B) | cholesterol and steroid molecules. |
| | C) | ketone bodies. |
| | D) | fatty acids and triglyceride molecules. |
|
|
|
| 24 | |
The two glycolytic intermediates that directly link glucose metabolism to the metabolism of triglycerides, and thereby linking carbohydrate to fat metabolism are |
| | A) | pyruvic acid and phosphoglyceraldehyde. |
| | B) | acetyl CoA and pyruvic acid. |
| | C) | phosphoglyceraldehyde and acetyl CoA. |
| | D) | glucose and pyruvic acid. |
|
|
|
| 25 | |
Which of the following energy storage nutrient molecules provides the greatest amount of energy in calories (kilocalories) per gram? |
| | A) | fat |
| | B) | carbohydrate |
| | C) | protein |
|
|
|
| 26 | |
The catabolism of fatty acids to produce energy occurs through the process of |
| | A) | lipogenesis. |
| | B) | lipolysis. |
| | C) | β-oxidation. |
| | D) | ketosis. |
|
|
|
| 27 | |
In the liver, when ATP is not needed. excess acetyl CoA molecules formed from fatty acid breakdown are often metabolized to |
| | A) | lactic acid. |
| | B) | ketone bodies. |
| | C) | cholesterol. |
| | D) | bile. |
|
|
|
| 28 | |
Amino acids must undergo _____________ prior to being used for metabolic reactions other than protein synthesis. |
| | A) | transamination. |
| | B) | β-oxidation. |
| | C) | oxidative deamination. |
| | D) | urea cycle. |
|
|
|
| 29 | |
The vitamin that acts as a coenzyme for transaminase enzymes is |
| | A) | niacin (B3). |
| | B) | riboflavin (B2). |
| | C) | pyridoxine (B6). |
| | D) | vitamin C. |
|
|
|
| 30 | |
Nonessential amino acids include |
| | A) | glycine. |
| | B) | histadine. |
| | C) | isoleucine. |
| | D) | valine. |
|
|
|
| 31 | |
The amino molecules used in the production of urea by the liver are produced by the catabolism of |
| | A) | carbohydrates. |
| | B) | proteins. |
| | C) | ketone bodies. |
| | D) | fats. |
|
|
|
| 32 | |
Which of the following is not a source of energy found circulating in the bloodstream? |
| | A) | glycogen |
| | B) | glucose and ketone bodies |
| | C) | lactic acid and amino acids |
| | D) | fatty acids |
|
|
|
| 33 | |
The ____ is the organ with an absolute requirement for blood glucose as its major energy source. |
| | A) | brain |
| | B) | heart |
| | C) | skeletal muscle |
| | D) | liver |
|
|
|
| 34 | |
Anaerobic metabolism of glucose results in an oxygen debt that is the amount of oxygen needed to metabolize the ______ that is produced. |
| | A) | carbon dioxide |
| | B) | lactic acid |
| | C) | glycogen |
| | D) | fatty acid |
|
|
|
| 35 | |
When glucose is catabolized under aerobic conditions, ________ will cross the mitochondrial wall and enter the Krebs cycle. |
| | A) | CO2 |
| | B) | pyruvate |
| | C) | lactate |
| | D) | acetyl CoA |
|
|
|
| 36 | |
Which of the following statements describes the role of the electron transport chain? |
| | A) | The electron transport chain makes ATP. |
| | B) | The electron transport chain produces CO2. |
| | C) | The electron transport chain is a reducing agent for NAD. |
| | D) | The electron transport chain is an oxidizing agent for FADH2. |
|
|
|
| 37 | |
When one NADH enters oxidative phosphorylation, how many ATP are produced in the cytosol? |
| | A) | 1.5 |
| | B) | 2 |
| | C) | 2.5 |
| | D) | 3 |
|
|
|
| 38 | |
Glycogen accounts for what approximately what percent of the stored energy in the body of a non-obese man? |
| | A) | less than 10% |
| | B) | 10-25% |
| | C) | 25-50% |
| | D) | more than 50% |
|
|
|
| 39 | |
Starting with acetyl CoA, each turn of the Krebs cycle will produce: |
| | A) | 2 FADH2, 1ATP, and 3 NADH |
| | B) | 1 FADH2, 1 ATP, and 3 NADH |
| | C) | 3 FADH2, 2 ATP, and 1 NADH |
| | D) | 1 FADH2, 3 ATP, and 2 NADH |
|
|
|
| 40 | |
Which of the following is not an example of an antioxidant? |
| | A) | NADH |
| | B) | glutathione |
| | C) | α-tocopherol |
| | D) | ascorbic acid |
|
|
.