N NH 3 NHCNH 2. 3 Lysine (Lys)

Transcription

1 Make sure You have FIVE Different C 110 May, 2007 Pages Including this Cover Page. Cover Page You may pick up your graded exam after 120 minutes Final Exam 5/08/07 until 12/01/07 DETAC TIS SEET AND USE AS A CVER SEET/SCRATC SEET. KEEP YUR WRK CVERED! BRIEFLY LK VER TE EXAM FIRST. SEE ALL TE INFRMATIN TAT IS PRVIDED FR YUR USE. YU MAY USE INFRMATIN PRVIDED ANYWERE N TIS EXAM. ALLCATE YUR TIME. ANSWER EAC F TE QUESTINS IN TE SPACE PRVIDED. C C 2 C C C C 2 C C C C C C C C C C C 2 C 2 C C C C C C glyceraldehyde dihydroxyacetone C 2 C 2 C C C C erythrose threose C 2 C C C C C C ribose C 2 C 2 C 2 C 2 C N C C 2 C 2 SC fructose galactose glucose C C N 2 C 2 C 2 N C N N NCN 2 N C C istidine (is) Methionine (Met) N 2 C (C Arginine (Arg) 2 ) 4 N 2 C N 2 C C Lysine (Lys) C C C Tyrosine (Tyr) C C 2 C 2 C C C C 2 CN 2 C C C N N C N C 2 C N C C Glutamic Acid (Glu) Asparagine (Asn) N C Isoleucine (Ile) C C 2 S Glycine (Gly) A C N Threonine (Thr) C (C 2 ) 12 B b C C Cysteine (Cys) C C C c C C C C C C a CNCR f C D 2 PC 2 C 2 N(C ) d g F E e Na C 2 C(C 2 )nc C(C 2 ) 7 C=C(C 2 ) 5 C i C C 2 h C(C 2 )n'c P C 2 C 2 N(C ) G C 2 C C 2 C(C 2 ) 7 C=C(C 2 ) 5 C C(C 2 ) 7 C=C(C 2 ) 5 C C(C 2 ) 7 C=C(C 2 ) 7 C C 2 C C C 2 C(C 2 )n'c P C(C 2 )nc C 2 C 2 N

2 Name (1 pts) C 110 May, minutes T A Page 1 of 4 Final Exam 20 pts 01) Complete each of the following with the correct word or phrase: With few exceptions an enzyme is principally composed of. A metal ion necessary for enzyme function is a(n). An organic molecule necessary for enzyme function is a(n). The following are enzyme names, what do these enzymes do? ydrolase xoreductase What specifically does Lactate dehydrogenase enzyme do?. Explain why enzymes work best over very narrow ranges of p and temperature: _. Explain briefly the lock & key mechanism of enzyme specificity:. Draw and label a graph showing the different responses of an enzyme as the concentration of substrate increases when a) the enzyme is not under the influence of an inhibitor; b) under the influence of a competitive inhibitor, and c) when it is under the influence of a non-competitive (allosteric) inhibitor. Explain briefly how a competitive enzyme inhibitor works: Explain briefly how an allosteric enzyme inhibitor works:

3 Name C 110 May, 2007 T A PAGE 2 of 4 Final Exam 21 pts 02) n the cover page, molecules labeled A- have various functional groups. Name the functional groups or structures indicated by the lower case letters: a-i (1 pt ea). Use the lowercase letter to indicate the functional groups described below: undergoes keto-enol tautomerism, could make a cholesteryl ester, will be acidic, Place the uppercase letter(s) from the cover sheet for the proper choices in the spaces provided: Which lipid is a female hormone? Which is an unsaturated oil.? ow many molecules of Br 2 will F react with? Are the double bonds in compound G : cis trans either (Circle). Which phospholipid is a sphingomyelin? Which have ethanolamine residues? Which phospholipid is phosphotidylcholene? Which phospholipid is a plasmalogen? Which compound is a soap? 21 pts 0) Complete the following reactions as indicated. a) Addition:: C C 2 CC C 2 C Condensation: C 2 C - 2 b) ydrolyse the ester: CC 2 C Na 2 c) of ester Acyl transfer reaction: NC C C 2 C Cl 2 C 2 C of salt formed d) ydrolysis: N IUPAC Name of compound Na 2 name side product IUPAC Name of compound e) Stepwise xidtion C 2 CC 2 C C [] []

4 Name C 110 May, 2007 T A PAGE of 4 Final Exam 20 pts 04) Using the Fischer carbohydrate structures on the cover sheet, draw and label the aworth templates below as β-ribose, α-fructose, β-glucose and then draw β-maltose, a disaccharide which is composed of glucose units, is digestible and reducing. Place asterisks (*) at the anomeric centers in each structure. C 2 C 2 C 2 C 2 $-Maltose is digestible because the link is α β (Circle) in the glucose unit $-maltose is a reducing sugar because Using the aworth structure for β-glucose above complete the chair hemiacetal structures, A for α-glucose and B for $-glucose: Place an asterisk (*) at the anomeric center in each structure (A & B). C 2 C 2 A) B) α-glucose A) is in equilibrium in solution with $-glucose B) in a process called:. The equilibrium mixture has twice as much B as A. Explain why this is so: 08 pts 05) Answer the questions below in the space provided. Show all atoms. a) Write the equation for the addition of a hydrogen ion to propene using structural formulas for the carbocation: (2 pts)) Explain why only one possibility exists. (1 pts) b) Write the structure of the species formed when the cation in part a) adds to a second propene molecule. ( pts) c) Describe the order of carbocation stability: > > > (2 pts)

5 Name C 110 May, 2007 T A PAGE 4 of 4 Final Exam 0 pts 06) Using the first-three-letter labels for aminoacids from the coversheet answer the following questions. (1 pt ea) a) Which of the amino acids have a phenol side group? b) Which of the amino acids will have a pi > 10? c) Which of the amino acids will have a pi < 4? d) Which polar amino acid has more than one tetrahedral stereocenter? which has none e) The primary structure of a protein is f) What two common secondary structures do proteins take? and. g) Describe the specific interactions which stabilize the secondary structure in each case (same order) (2 pts) and. (2 pts) Describe the locations of the side-groups in each of the two structures above and (same order, 2 pts). h) Name the five aminoacids that are found in the active sites of over 60% of all enzymes: (5 pts). i) Name the ionic link that stabilizes the tertiary structure of proteins: j) Name the covalent link that stabilizes the tertiary structure of proteins. k) Draw the structure of the tetrapeptide Lys-Asn-Thr-is (with Lys being the N-terminus) at its isoelectric point: ( pts): Is the tetrapeptide ink) hydrophilic hydrophobic (circle)? Acidic Basic Neutral (circle)? l) Draw the two enantiomers of L-isoleucine and assign (label) them as to the R/S system: (hint this is the 2 nd stereocenter, show your priorities and rotation). (6 pts)