Questions:

1. Di Beatty has a metabolic acidosis resulting from an increased hepatic production of ketone bodies. For a patient with this disorder a screening test using the Nitroprusside reaction can test for the presence of ketones in the blood. Which of the following molecular structures is a ketone?
  1. R-CH2-OH
  2. R–CHO
  3. (R–CH2-)2C=O
  4. R–COOH
  5. R–CH2-O-CH3
2. All of the following statements regarding oxidation-reduction reactions are true EXCEPT?
  1. Carbon atoms in organic molecules have different oxidation states depending on whether they are involved in single or double bonds or whether they are part of an alcohol, aldehyde, ketone, or carboxylic acid
  2. The oxidation of a molecule involves the loss of electrons
  3. The reduction of a molecule involves the addition of electrons
  4. When CH3-CH2-OH is converted to CH3-CHO (ethanol converted to acetaldehyde), ethanol is oxidized.
  5. When CH3-CH2-OH is converted to CH3-CHO (ethanol converted to acetaldehyde), ethanol is reduced.
3. All of the following are characteristics of the reduction of a biological molecules EXCEPT
  1. Gains hydrogen atoms
  2. Gains oxygen atom
  3. Looses oxygen atoms
  4. Gains electrons
4. Which of the following two substrates undergo a condensation reaction to form an ester?
  1. Alcohol + Alcohol
  2. Acid + Acid
  3. Acid + Alcohol
  4. Phosphoric acid + Phosphoric acid
  5. Acid + Amine
5. Hydrolysis of a thioester produces a
  1. Carboxylic acid + alcohol
  2. Phosphoric acid + alcohol
  3. Carboxylic acid + sulfhydryl compound
  4. Carboxylic acid + carboxylic acid
  5. Carboxylic acid + amino group
6. If a monosaccharide has 6 carbon atoms and the carbonyl group is on the number 3 carbon atom, the sugar is called a
  1. aldohexose
  2. ketohexose
  3. aldopentose
  4. ketopentose
  5. aldotriose
7. If a monosaccharide has 5 carbon atoms and the carbonyl group is on the number 1 carbon atom, the sugar is called a
  1. ketohexose
  2. aldohexose
  3. aldopentose
  4. ketopentose
  5. aldotriose
8. A carbon atom is said to be asymmetric
  1. If it has four different chemical groups attached to it
  2. If it has both single and double bonds
  3. If it forms an achiral center
  4. If it contains less than four bonds
  5. None of the above describes an asymmetric carbon
9. You are presented with two compounds and they both have the formula C6H12O6. They differ only in their orientation about the number 3 asymmetric carbon atom. They are
  1. epimers
  2. sterioisomers
  3. carbohydrates
  4. isomers
  5. All of the above
10. Which of the following characteristics would allow you to distinguish between a stereoisomer and an epimer?
  1. Epimers have the same chemical formula but differ in the position of the hydroxyl groups on one or more of their asymmetric carbons
  2. Stereoisomers are like one another with respect to which atoms are joined to which other atoms but have different chemical formulas
  3. Stereoisomers have the same chemical formula but differ in the position of the hydroxyl groups on one or more of their non-asymmetric carbons
  4. Epimers are stereoisomers that differ in the orientation of the hydroxyl group about a single asymmetric carbon atom
  5. Stereoisomers are epimers that differ in the orientation of the hydroxyl group about number 3 asymmetric carbon atom
11. D-Galactose and D-Mannose are aldohexoses that differ in the orientation of hydroxyl groups at two different carbon atoms. They are
  1. Enantiomers of each other
  2. Isomers of each other
  3. Anomers of each other
  4. Epimers of each other
  5. Mirror images of each other
12. When glucose is dissolved in water, the straight chain form can produce either an α-hemiacetal or a β-hemiacetal. All of the following are characteristics associated with α-D-Glucopyranose and b-D-Glucopyranose, EXCEPT?
  1. Conversion of one isomer to the other is referred to as mutarotation
  2. Once the anomeric carbon atom forms a bond with another molecule it is locked in either the alpha or beta position
  3. α-D-Glucopyranose can not be converted into b-D-Glucopyranose
  4. Enzymes differentiate between α-D-Glucopyranose and b-D-Glucopyranose, and are specific for only one of them
  5. α-D-Glucopyranose and b-D-Glucopyranose are two different configurations of the same molecule
13. When the number 6 carbon atom of glucose is oxidized to a carboxyl group at pH = 7, the new compound is called
  1. Fructose
  2. Glucuronate
  3. Gluconate
  4. Sorbitol
  5. Ribose
14. Which of the following monosaccharides is a result of the reduction of the glucose aldehyde group?
  1. Sorbitol
  2. Gluconic acid
  3. Glucuronic acid
  4. Galactitol
  5. Ribose
15. Which of the following statements is true regarding the formation of a glycosidic bond?
  1. A glycosidic bond is formed when the OH or NH of the anomeric carbon reacts with the hydroxyl group of another molecule
  2. The anomeric carbon of a glycosidic bond is always in the beta position
  3. A glycosidic bond is formed when the hydroxyl group of the anomeric carbon reacts with the OH or NH group of another molecule
  4. The anomeric carbon of a glycosidic bond is always in the alpha position.
  5. A glycosidic bond is formed between glycose and sidose.
16. Eicosanoids are a group of hormone-like compounds produced by many cells in the body. They include the prostaglandins, thromboxanes and leukotrienes. They are synthesized from polyunsaturated fatty acids containing 20 carbon atoms and 3, 4, or 5 double bonds. Which of the following fatty acids is the precursor to the eicosanoids?
  1. Palmitic acid
  2. Palmitoleic acid
  3. Oleic acid
  4. Arachidonic acid
  5. Stearic acid
17. Which of the following is an example of an 18:0 saturated fat?
  1. Palmitoleic acid
  2. Arachidonic acid
  3. Stearic acid
  4. Oleic acid
  5. Palmitic acid
18. Using delta numeric nomenclature, which of the following would be used to describe a fatty acid with 18 carbons and 1 double bond, which is located at position 9 of the carbon chain?
  1. 18:9Δ1.
  2. 18:9ω1
  3. 18:1Δ9
  4. 18:1ω9
  5. 18:9Δ9
19. Arachidonic acid has 20 carbon atoms and four double bonds. It may be described as ω-6 or as 20:4,Δ5,8,11,14 The ω-6 indicates that there are no double bonds between carbon atoms
  1. 20 and 15
  2. 1 and 6
  3. 20 and 14
  4. 20 and 5
  5. 5 and 14
20. Which of the following characteristics regarding the length and saturation of the fatty acids are true?
  1. The melting point of a fatty acid decreases with chain length and increases with the degree of unsaturation
  2. The melting point of a fatty acid increases with chain length and decreases with the degree of unsaturation
  3. The fatty acid composition of membrane phospholipids determines the fluidity of membranes at body temperature
  4. A and C are correct
  5. B and C are correct
21. Unsaturated fats such as those in vegetable oils are liquids at room temperature and thus, contribute to the fluidity of our cellular membranes due to their
  1. Having lower melting points
  2. Having many double bonds
  3. Having higher melting points
  4. Both A & B
  5. Both B & C
22. Which of the following is true of a triacylglycerol?
  1. A triacylglycerol is formed when a fatty acid reacts with the hydroxyl group attached to the 3rd carbon of the glycerol moiety
  2. A triacylglycerol rarely contains the same fatty acid at all 3 positions
  3. A triacylglycerol is formed when 3 fatty acids reacts with the 3 hydroxyl groups of the glycerol moiety
  4. A triacylglycerol always contains the same fatty acid at all 3 positions
  5. B and C are both correct
23. The three OH groups on glycerol can react with one, two, or three fatty acids to form
  1. Amide groups
  2. Anhydride groups
  3. Ester groups
  4. Carboxyl groups
24. The components of phosphatidic acid are?
  1. 1 Phosphate, 1 glycerol, and 1 choline
  2. 1 Phosphate, 1 glycerol, and 1 lecithin
  3. 1 Phosphate, 1 glycerol, and 1 fatty acid
  4. 1 Phosphate, 1 glycerol, and 2 fatty acids
  5. 1 Phosphate, 1 glycerol, and 3 fatty acids
25. Phospholipids such as phosphatidylcholine contain fatty acids esterified at which position of the glycerol molecule
  1. Position 1 only
  2. Position 3 only
  3. Position 1 and 2
  4. Both position 1 and 3
  5. Both position 2 and 3
26. Lysolecithin is produced by
  1. Addition of an acyl group to the glycerol molecule of lecithin
  2. Addition of a fatty acid to the phosphate group of lecithin
  3. Addition of choline to the phosphate group of lecithin
  4. Removal of a fatty acid (acyl) group from lecithin
  5. Removal of phosphate group from lecithin
27. One difference between sphingomyelin and lecithin is that
  1. Sphingomyelin contains choline and lecithin does not
  2. Sphingomyelin contains an acyl (fatty acyl) group and lecithin does not
  3. Sphingomyelin contains phosphate and lecithin does not
  4. Sphingomyelin contains a ceramide and lecithin does not
  5. Sphingomyelin contains a glycerol and lecithin does not
28. All of the following are characteristics of cholesterol, EXCEPT:
  1. Cholesterol contains 4 rings known as the steroid nucleus
  2. Cholesterol is synthesized in animals but not plants
  3. Cholesterol is the parent compound from which other steroids are produced including bile salts, bile acids, adrenocortical steroids and sex hormones
  4. Cholesterol contains one hydroxide group
  5. Cholesterol is very water-soluble
29. By definition, amphipathic molecules contain both hydrophobic and hydrophilic regions. Which of the following statements correctly identifies the hydrophobic and hydrophilic regions of cholesterol?
  1. The steroid nucleus of cholesterol is hydrophilic and the carboxyl and hydroxyl groups are hydrophobic
  2. The carboxyl group of cholesterol is hydrophobic and the steroid nucleus and hydroxyl groups are hydrophilic
  3. The steroid nucleus of cholesterol is hydrophobic and the hydroxyl group is hydrophilic
  4. The hydroxyl group of cholesterol is hydrophobic and the steroid nucleus is hydrophilic
  5. The carboxyl and hydroxyl groups of cholesterol and the steroid nucleus are all hydrophilic
30. Which characteristic of bile acids helps them act as emulsifying agents in the intestine, helping to prepare dietary triacylglycerol and other complex lipids for degradation by pancreatic digestive enzymes?
  1. They have two or three hydroxyl groups and a carboxyl group
  2. They have steroid nucleus that is hydrophobic
  3. The molecules have both a polar and a nonpolar face
  4. They are amphipathic
  5. All of the above
31. Which of the following statements correctly describes the α-carbon of most amino acids?
  1. It contains a hydroxyl group, an amino group and a side chain
  2. It contains a carboxyl group, an amino group and a side chain
  3. It contains a sulfhydryl group, an amino acid and a side chain.
  4. It is covalently bonded to 4 other carbons
  5. All of the constituents vary from one amino acid to another
32. Which of the following contains a pyrimidine base?
  1. Thymine
  2. Adenine
  3. Guanine
  4. A and C
  5. B and C
33. Adenosine Triphosphate (ATP) is:
  1. Nucleotide
  2. Nucleoside
  3. Nucleoside triphosphate
  4. A and C
  5. A and B
34. Free radicals are atoms that have an unpaired electron in the outer orbital which makes them:
  1. Highly reactive and able to initiate chain reactions by extracting electrons from neighboring molecules
  2. Very stable
  3. Less destructive and potent catalysts
  4. Unreactive
  5. Very useful for stabilizing lipid membranes
35. Which of the following is NOT a free radical?
  1. Hydroxide radical
  2. Superoxide radical
  3. Nitrogen dioxide
  4. Oxygen
36. A semiquantitative reagent strip (ketostrip) or Acetest tablets contain nitroprusside that is used to estimate the level of ketone groups in someone who is ketoacidotic. Which of the following ketone bodies is responsible for most of the color developed in with nitroprusside?
  1. Acetoacetate
  2. Acetone
  3. Beta-hydroxybutyrate
37. Given a basic solution containing adenosine monophosphate, glucose, fructose and galactose, which of these compounds will NOT undergo a positive reducing sugar test?
  1. AMP
  2. Glucose
  3. Galactose
  4. Fructose
38. Which functional group is oxidized as it donates electrons to copper in the reducing sugar test?
  1. Alcohol group
  2. Hydroxyl group
  3. Aldehyde group
  4. Ketone group
39. The glucose oxidase test is _______ for glucose and oxidizes glucose to ________:
  1. Specific ; Glucorunate
  2. Specific ; Gluconate
  3. Nonspecific : Hydrogen peroxide
  4. Nonspecific ; Glucuronate
  5. Nonspecific ; Gluconate
40. The pKa for uric acid is 5.7. At pH = 4 in the urine, most of the compound is in the form of
  1. Uric acid
  2. Sodium Urate
41. A 47 year old woman presents to her physician’s office complaining of a severe throbbing pain in her right big toe that began 8 hours earlier. She is diagnosed with acute gouty arthritis (podagra). Which compound is responsible for the severe pain experienced by this patient?
  1. Uric acid
  2. Sodium urate crystals
  3. Calcium pyrophosphate crystals
  4. All of the above
42. Refer to the structures in Figure 1 below. Which column contains the structure for an aldotriose?
  1. Column A
  2. Column B
  3. Column C
  4. Column D
  5. Column E
Figure 1.Five possible curves for an allosteric activator added to an allosteric enzyme.
43. Refer to the structures in Figure 1 above. Which column contains glucuronic acid (glucuronate)
  1. Column A
  2. Column B
  3. Column C
  4. Column D
  5. Column E
44. Refer to the structures in Figure 2 below. Which column contains the structure for pyrimidine?
  1. Column A
  2. Column B
  3. Column C
  4. Column D
Figure 2.Five possible curves for an allosteric activator added to an allosteric enzyme.
45. Refer to the structures in Figure 3 below. Which row contains the structure for palmitic acid (palmitate)?
  1. Column A
  2. Column B
  3. Column C
  4. Column D
  5. Column E
Figure 3.Five possible curves for an allosteric activator added to an allosteric enzyme.
46. Three ketone bodies, ________, ________, and ________ are released into the blood from the ________
  1. Acetaldehyde, acetone, beta-hydroxybutyrate; muscle
  2. Acetoacetate, provolone, and beta-hydroxybutyrate; liver
  3. Acetoacetate, acetone, and alpha-hydroxybutyrate; brain
  4. Acetoacetate, acetone, and beta-hydroxybutyrate; liver
  5. Acetoacetate, acetone, and beta-hydroxybutyrate; kidney

Answers:

1. Answer: C. Chapter 5, Objective 1: Given a biological molecule, be able to name the functional groups. Back to question 1.
2. Answer: E. Chapter 5, Objective 2: Be able to tell if a biological molecule is oxidized or reduced. Back to question 2.
3. Answer: B. Chapter 5, Objective 2: Be able to tell if a biological molecule is oxidized or reduced. Back to question 3.
4. Answer: C. Chapter 5, Objective 3: What are the substrates for a reaction that forms an ester, a thioester, an amide, a phosphoester, and an acid anhydride? What are the products of a reaction that hydrolyzes an ester, a thioester, an amide, a phosphoester, and an acid anhydride? Back to question 4.
5. Answer: C. Chapter 5, Objective 3: What are the substrates for a reaction that forms an ester, a thioester, an amide, a phosphoester, and an acid anhydride? What are the products of a reaction that hydrolyzes an ester, a thioester, an amide, a phosphoester, and an acid anhydride? Back to question 5.
6. Answer: B. Chapter 5, Objective 4 and 5: Be able to recognize an aldose and a ketose. Be able to recognize a triose, tetrose, pentose, hexose, heptose! Back to question 6.
7. Answer: C. Chapter 5, Objective 4 and 5: Be able to recognize an aldose and a ketose. Be able to recognize a triose, tetrose, pentose, hexose, heptose! Back to question 7.
8. Answer: A. Chapter 5, Objective 6: Be able to recognize an asymmetric carbon atom. Back to question 8.
9. Answer: E. Chapter 5, Objective 7: Given two compounds, be able to tell whether they are stereoisomers or epimers! Back to question 9.
10. Answer: D. Chapter 5, Objective 7: Given two compounds, be able to tell whether they are stereoisomers or epimers. Back to question 10.
11. Answer: B. Chapter 5, Objective 7: Given two compounds, be able to tell whether they are stereoisomers or epimers. Back to question 11.
12. Answer: C. Chapter 5, Objective 8: What is the difference between alpha- and beta-D-glucopyranose? Back to question 12.
13. Answer: B. Chapter 5, Objective 9: Compare glucuronate, gluconate, and sorbitol with glucose. Back to question 13.
14. Answer: A. Chapter 5, Objective 9: What is the most important reason for maintaining a physiological pH? Back to question 14.
15. Answer: C. Chapter 5, Objective 10: Be able to identify alpha-O, alpha-N, Beta-O and Beta-N-glycosidic bonds. Back to question 15.
16. Answer: D. Chapter 5, Objective 11: Be able to identify the structure of a fatty acid. Be able to differentiate between Palmitic acid, Stearic acid, Oleic acid, a-linolenic acid and Arachidonic acid. Back to question 16.
17. Answer: C. Chapter 5, Objective 11: Be able to identify the structure of a fatty acid. Be able to differentiate between Palmitic acid, Stearic acid, Oleic acid, a-linolenic acid and Arachidonic acid. Back to question 17.
18. Answer: C. Chapter 5, Objective 12: Be able to use delta-numeric and omega nomenclature to identify the position of double bonds. Back to question 18.
19. Answer: A. Chapter 5, Objective 12: Be able to use delta-numeric and omega nomenclature to identify the position of double bonds. Back to question 19.
20. Answer: E. Chapter 5, Objectives 13: Why is the length of the fatty acids in phospholipids important? Note Textbook Error: "The melting point decreases with degree of saturation," is incorrect. Back to question 20.
21. Answer: D. Chapter 5, Objectives 13: Why is the length of the fatty acids in phospholipids important? Back to question 21.
22. Answer: E. Chapter 5, Objective 14: Recognize a mono, di and triacylglycerols. Back to question 22.
23. Answer: C. Chapter 5, Objective 14: Recognize a mono, di and triacylglycerols. Back to question 23.
24. Answer: D. Chapter 5, Objective 15: Be able to recognize the names of and the structures of phosphatidic acid, phosphatidylcholine, and lecithin. Back to question 24.
25. Answer: C. Chapter 5, Objective 15: Be able to recognize the names of and the structures of phosphatidic acid, phosphatidylcholine, and lecithin. Back to question 25.
26. Answer: D. Chapter 5, Objective 16: What does the lyso in Lysolecithin indicate? Back to question 26.
27. Answer: D. Chapter 5, Objective 17: Be able to tell the difference between Sphingomyelin and lecithin (phosphatidylcholine). Back to question 27.
28. Answer: E. Chapter 5, Objective 18: Be able to recognize cholesterol and any compound derived from it. Back to question 28.
29. Answer: C.  Chapter 5, Objective 19:Be able to identify the hydrophilic and hydrophobic regions of the cholesterol molecule and bile acids. Back to question 29.
30. Answer: E.  Chapter 5, Objective 19: Be able to identify the hydrophilic and hydrophobic regions of the cholesterol molecule and bile acids. Back to question 30.
31. Answer: B.  Chapter 5, Objective 20: Be able to identify the alpha amino and the alpha carboxyl for any alpha amino acid. Back to question 31.
32. Answer: A. Chapter 5, Objective 21: Be able to recognize the structure of a purine and a pyrimidines base. Be able to identify the structure of adenine, guanine or thymine. Back to question 32.
33. Answer: D. Chapter 5, Objective 22: Be able to identify the structure of adenosine, adenosine monophosphate, adenosine diphosphate and adenosine triphosphate and state whether they are nucleosides or nucleotides. Back to question 33.
34. Answer: A. Chapter 5, Objective 23: Define a free radical. Back to question 34.
35. Answer: D. Chapter 5, Objective 24: Be able to recognize the structure and name three of the free radicals generated in human tissues. Back to question 35.
36. Answer: A. Chapter 5, Objective 26: Concerning Di Abetes, what three compounds were raised in her blood that caused acidosis? Where were they made? Which one was not measured by the nitroprusside reaction and why wasn’t it measured? Back to question 36.
37. Answer: A Chapter 5, Objective 27: Concerning Di Abetes, given a basic solution containing adenosine monophosphate, glucose, fructose and galactose, which of these compounds will undergo a positive reducing sugar test? Why? Back to question 37.
38. Answer: C. Chapter 5, Objective 27: Concerning Di Abetes, given a basic solution containing adenosine monophosphate, glucose, fructose and galactose, which of these compounds will undergo a positive reducing sugar test? Why? Back to question 38.
39. Answer: B Chapter 5, Objective 28: Concerning Di Abetes, how does the glucose oxidase test work and why is the test specific? What are the products of the enzyme reaction? Back to question 39.
40. Answer: A. Chapter 5, Objective 29: Concerning Lotta Topaigne, Given that the pKa for uric acid is 5.7 and that uric acid is 20 times less soluble than sodium urate, explain which is more likely to precipitate in the toe and which is more likely to precipitate in the kidney tubule. Back to question 40.
41. Answer: B. Chapter 5, Objective 29: Concerning Lotta Topaigne, Given that the pKa for uric acid is 5.7 and that uric acid is 20 times less soluble than sodium urate, explain which is more likely to precipitate in the toe and which is more likely to precipitate in the kidney tubule. Back to question 41.
42. Answer: E. Chapter 5, Objectives 4 and 5: "Be able to recognize a aldose and ketose.!"" Be able to recognize a triose, tetrose, pentose, hexose, heptose!"
43. Answer: B. Chapter 5, Objective 9: "Compare glucuronate, gluconate, and sorbitol with glucose!"
44. Answer: C. Chapter 5, Objective 21, "Be able to recognize the structure of a purine and a pyrimidine base. Be able to identify the structure of adenine, guanine or thymine."
45. Answer: A. Chapter 5, Objective 11, "Be able to identify the structure of a fatty acid. Be able to differentiate between Palmitic acid, Stearic acid, Oleic acid, a-Linolenic acid and Arachidonic acid."
46. Answer: D. Chapter 5, Objective 25, "Concerning Di Abetes, what two compounds were raised in her blood that caused acidosis? Where were they made?"