BUFFERS, AMINO ACIDS, PEPTIDES and PROTEIN - Biochemistry - Exam, Exams of Biochemistry

Download BUFFERS, AMINO ACIDS, PEPTIDES and PROTEIN - Biochemistry - Exam and more Exams Biochemistry in PDF only on Docsity! BUFFERS, AMINO ACIDS, PEPTIDES and PROTEIN. Put down a number that matches the question asked ONLY NUMBERS (Questions 1-45, 2 PTS each) ____1. The pH of a neutral solution ____2. The [H+] concentration of a neutral solution ____3. The [OH-] concentration of a neutral solution ____4. The ion product (Kw) or water ____5. The pH of a 10-3 M HCl solution ____6. The pH of a 10-3 M solution of acetic acid (pKa =4.7) that is 10% ionized. ____7. The number of equivalents of base required to reach the pK point of fully protonated acetic acidic. ____8. The approximate pKa of an -COOH group of an amino acid. ____9. The approximate pKa of an -NH2 group of an amino acid. ___10. The approximate pH when glycine exist entirely as a zwitterion ___11. The pKa of the imidazole group of histidine ___12. The number of equivalents of base that are required to titrate all the protons in fully protonated aspartate ___13. The minimum number of (lysine + arginine) residues in a peptide cleaved into 4 fragments by trypsin ___14. The highest pKa value for an R group on an amino acid ___15. The number of peptide bonds in a tripeptide ___16. The number of iron atoms in a molecule of myoglobin ___17. The number of porphyrin ring structures in a molecule of hemoglobin ___18. The approximate number of residues in one turn of an alpha helix ___19. The number of N-terminals in a tetrameric protein ___20. A number that would signify no cooperativity in a Hill plot. CARBOHYDRATES, FATTY ACIDS and NUCLEIC ACIDS ___21. The number of carbons atoms in glucose ___22. The number of carbon atoms in lactose ___23. The number of carbon atoms in oleic acid ___24. The number of carbon atoms in ATP ___25. The number of fatty acids attached to a diacylglycerol ___26. The number of phosphate groups in a molecule of lecithin ___27. The number of cis double bonds in arachidonic acid. ___28. The ratio of C/N (carbon to nitrogen) in the base adenine. ___29. The number of hydrogen bonds that join cytosine to guanine in DNA ___30. The S value for the small subunit of a mammalian ribosome ENZYMES, ENERGY and MEMBRANES ___31. The number of micromoles of substrate changed per unit time when 3 units of enzyme activity are observed ___32. The ratio of [ES] to [E]total when [S] equals the numerical value for Km ___33. The value for G when a reaction is at equilibrium ___34. The charge on a molecule of cholesterol oleate at pH 7 ___35. The molecules of S converted per minute per molecule of enzyme whose turnover number is 60 sec-1 _______________________ Name A Docsity.com Questions 36-45 (Write in the letter (s) that match the description). All must be correct to earn one point. A. Sucrose D. Cholesterol B. Glycerol E. CO2 C. Hemoglobin F. Sphingomyelin 36. Arranged A-F by increasing molecular weight: ____ < ____ < ____ < ____ < ____ < ____ 37. 3 are associated with molecules classified as lipids: ____ and ____ and ____ 38. One is a protein: ____ 39. One can be hydrolyzed to two components by mild acid: ____ 40. One assists in the release of oxygen from hemoglobin: ____ 41. One has phosphate in its structure: ____ 42. 2 have nitrogen atoms in their structure: ____ and ____ 43. 2 are found in the cell membrane bilayer: ____ and ____ 44. One is a carbohydrate: ____ 45. One is a gas: ____ ANSWER QUESTIONS 1-15 on the scantron 2 PTS for a correct response. ONLY ONE ANSWER IS CORRECT In this course we stressed the STRUCTURE-FUNCTION principle to rationalize why certain molecules are chosen to perform the functions of living cells. See if you have grasped this principle. 1. Proteins owe their strength to covalent bonds that: a) have double-bond character and join amino acids together b) have the same bond strength as amide bonds c) are electrostatic and depend on the pH of the solution to unite (+) and (-) charges d) are hydrophobic bonds that hold groups together by van der Waals forces e) all of the above are examples of covalent bonds found in proteins 2. A friend asks your advice as to whether lettuce will contribute to tooth decay. You reply. a) Yes, because lettuce is composed of cellulose which is broken down to glucose by -amylases in saliva b) Yes, because -amylases in saliva are able to digest the cellulose in the lettuce c) No, because our amylase enzymes are unable to digest cellulose d) Yes, because our enzymes break down all polysaccharides and release glucose that could cause tooth decay e) No, because cellulose is a fiber that is digested in the intestine, not the mouth 3. Which of the following does not have D-ribose as part of its structure: a) ATP b) RNA c) NAD+ d) DNA e) c and d 4. Spot the molecule whose solubility property is different from the others: a) L-fructose b) L-tryptophan c) D-glycerol d) -D-glucose e) oleic acid 5. Spot the molecule that is NOT a building block of a larger molecule: a) L-isoleucine b) D-galactose c) L-ascorbate d) guanine e) stearic acid 6. Spot the molecule that would have the most difficulty penetrating the cell membrane: a) hemoglobin b) LDL c) D-glucose d) cholesterol e) L-tyrosine 7. Other than serine, which amino acid residue is apt to be at the active site of a serine protease? a) glycine b) glucose c) sialic acid d) glutathione e) histidine 8. Which enzyme below uses NAD+ as a substrate a) alcohol dehydrogenase c) diphtheria toxin A e) a, b, c, d b) DNA ligase d) lactate dehydrogenase LETTERS ONLY Docsity.com