C C C C C COH CH 2 OH H C C H OH HOCH 2 HCH C O. glyceraldehyde dihydroxyacetone CH 2 OH erythrose. threose. ribose CH 2 OH CH 2 OH H C OH.

Transcription

1 Make sure You have FIVE Different 110 April 29, 2008 Pages Including this over Page. over Page You may pick up your graded exam after 120 minutes Final Exam 5/1/08 until 12/01/08 DETA TIS SEET AND USE AS A VER SEET/SRAT SEET. KEEP YUR WRK VERED! 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. ALLATE YUR TIME. ANSWER EA F TE QUESTINS IN TE SPAE PRVIDED glyceraldehyde dihydroxyacetone 2 erythrose threose 2 2 ribose 2 2 fructose 2 galactose 2 glucose A a B b ( 2 ) n' 3 P ( 2 ) n N 3 ( 2 ) 12 f N R 2 P 2 2 N( 3 ) c g E ( 2 ) 7 =( 2 ) 5 3 ( 2 ) 7 =( 2 ) 5 3 ( 2 ) 7 =( 2 ) 7 3 D d F i 3 h 2 2 l 3 e ( 2 ) n 3 ( 2 ) n' 3 P j 2 k 2 2 N( 3 ) 3 N S 3 Methionine (Met) N 3 NN 2 N Arginine (Arg) 2 N 3 2 Tyrosine (Tyr) 2 2 N 3 Glutamic Acid (Glu) 2 N 2 N 3 Asparagine (Asn) N Proline (Pro) ysteine (ys) N 3 Glycine (Gly) N 3 N 3 N 3 2 S Isoleucine (Ile) 3 Threonine (Thr)

2 Name (1 pts) 110 April 29, minutes T A Page 1 of 4 Final Exam 22 pts 01) omplete each of the following with the correct word or phrase: With few exceptions an enzyme is principally composed of A cofactor is. A coenzyme is. The following are enzyme names, what do these enzymes do? Transferase Lyase Ligase What specifically does Lactate dehydrogenase enzyme do? it is classified as a(n). Explain why enzymes work best over very narrow ranges of p and temperature:. Explain briefly the lock & key mechanism of enzyme specificity:. Explain briefly how the induced fit model differs?. 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 regulator works:

3 Name 110 April 29, 2008 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-l (1 pt ea). Place the uppercase letter(s) from the cover sheet for the proper choices in the spaces provided: Which lipid molecule will give a positive Benedict s test?. Which lipid is a triacylglycerol? What physical phase will this lipid likely have at 25E? Are the double bonds in compound : cis trans either (ircle). ow many molecules of Br 2 will E react with? Which phospholipid is a sphingomyelin? Which have ethanolamine residues? Which phospholipid is phosphotidylcholene? 21 pts 03) omplete the following reactions as indicated. a) Make the ester: 3 2 l Which phospholipid is a plasmalogen? IUPA name IUPA name of ester formed side product b) ydrolyse the ester: 2 3 Na 2 c) IUPA name of ester Acyl transfer reaction: IUPA name of salt formed IUPA name ( 3 2 ) 2 N d) ydrolysis: N IUPA Name of compound Na 2 IUPA name side product IUPA Name of compound e) Stepwise xidtion 2 ( 3 ) 2 [] [] IUPA name IUPA name IUPA name

4 Name 110 April 29, 2008 T A PAGE 3 of 4 Final Exam 26 pts 04) Using the Fischer carbohydrate structures and the aworth templates on the cover sheet, draw aworth structures for A) β-fructose and B) α-glucose and ) sucrose, a disaccharide which is composed of glucose and fructose and is digestible but non reducing. Place asterisks (*) at the anomeric centers in each structure. A) B) ) Explain why sucrose is digestible?. Explain why sucrose is not a reducing sugar?. Why does sucrose not need an α or β designation? Using the aworth template on the coversheet draw the aworth representations for A) α-fructose B) β- ribose ) β-2-deoxyribose Place an asterisk (*) at the anomeric center on A & B. A) B) ) Explain briefly the significance of the transformation of B) into ). l) Determine the R/S system designation for each of the two stereocenters of threose (shown on the coversheet). m) All natural sugars have the R S (ircle) configuration at the stereocenter.

5 Name 110 April 29, 2008 T A PAGE 4 of 4 Final Exam 07 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 pt) b) Write the structure of the species formed when the cation in part a) adds to a second propene molecule. (2 pts) c) What is the type of substance formed as a result of the sequential addition of many propene units to the carbocation formed in a)? (2 pts) 22 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 < 5? c) Which of the amino acids will have a pi > 7? d) Which non-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) h) Name the covalent link that stabilizes the tertiary structure of proteins: Write a general chemical equation illustrating the formation of this link using the amino acid(s) involved. (2 pts): i) Name the ionic link that stabilizes the tertiary structure of proteins: Which two amino acids from the cover sheet would pair in this way?. j) Draw the structure of the tetrapeptide: Met-Arg-Asn-Thr at its isoelectric point (with Met being the N-terminus) (3 pts): k) Is the tetrapeptide in j) hydrophilic hydrophobic (circle)? Why?.