Sample mid-quarter exam 1 (winter 2015)

Transcription

1 Chemistry 256 Sample mid-quarter exam 1 (winter 2015) 1. Which one of the following processes is not stimulated by insulin? a. Glucose uptake in muscle (t-j1.7f '-''";r ) b. Dephosphorylation of glycogen synthase in muscle -'lc.h\kat,.s ~JtJI'YtY c. Glycolysis in the liver d. Dephosphorylation of glycogen synthase in liver G;>Ail of the processes listed are stimulated by insulin 2. a Which enzyme would you use to remove a phosphate group from the enzyme glycogen phosphorylase a to form glycogen phosphorylase b Phosphorylase kinase Protein kinase ()>hosphoprotein phosphatase Glucose Phosphorylase b. Would this event activate o~r have no effect on the enzyme glycogen phosphorylase? c. The above event is considered a (circle all that apply): ~t modification of an enzyme Allosteric modification of an enzyme Genetic modification of the enzyme ~le of an enzymatic cascade 3 Cyclic AMP is considered a: Hormone Steroid ~ond messenger A receptor Enzyme 4. Chylomicrons contain which molecules: Acety-CoA ~lesterol esters Glycogen Isoprene pyrophosphate (J)iacylgly~rides

2 5 Circle which below would give a membrane a higher melting point a Incorporation of more cholesterol Cii7 Longer Chain lengths of the fatty acid components Less unsaturation of the fatty acid Cross linking of fatty acid components 6. For integral proteins associated with cell membranes what type of amino acid residues would be found exclusively within the membrane. l\)0'1\ - r c)' (;\("" 7 While fatty acids are most often formed by the condensation of_-carbon units, isoprenoids are assembled from _-carbon units. a.5,3 b. 4, 2 c. 2, 3 (g) 2, 5 e. 3,4 8. Which enzyme catalyzes the key regulatory step of cholesterol synthesis? a. b-ketothiolase b. HMG-CoA synthase (S:>HMG-CoA reductase d. mevalonate kinase e. squalene monooxygenase 9. In Gluconeogenesis the steps that are simply the reverse of Glycolysis ~ c;)) Have a ~G that is near o. ~ Have a ~G that is a large + value c) Have a ~G that is a large- value d) Are considered the rate control steps e) All step are the reverse of glycolysis 10. If the liver is analyzed, and the ratio of phosphorylase a (active form) to phosphorylase b is found what processes would probably be occurring? Gluconeogenesis Glycolysis L:Blycogen breakdown Glycogen build up (synthesis)

3 ---~ Which synthetic pathway(s) does the class of drugs called 'statins' effect Gluconeogenesis Glycolysis, Glycogen breakdown Glycogen build up (9holesterol synthesis Fatty acid synthesis. 12. Which pathways does Acetyl CoA participate in (as a reagent or product)? Gluconeogenesis Glycolysis Glycogen breakdown Glycogen build up C;Xholesterol synthesis ~eta oxidation of fats ~itric acid cycle Cfatty Acid synthesis Terpenes ~-<o Spingolipids~ 9 0~ ~ <>- f - ' 0 - l,j.il.-cti-cpol oe> ~" I _,.. o/ \ 4.1 ~ti -,... t\$ o-:.c. -tz.. '!'.I.,. sa u 14. Which molecules drawn above would you attribute the property of amphipathic. """'~'l"r',.c.p'\' :s Sf" I "''i() I, f'i!ls 15. Which processes below consume more energy than they produce? (consume ATP, NADPHetc) Cf;.Iuconeogenesis Glycolysis Citric acid cycle ~holesterol synthesis Pentose-f)hosphats-pathway- JJ~ ~ '4A~ Fatty acid oxidation ~tty acid biosynthesis 1 r fa~ll.- at"b~tt-hci\tl 16. What make the isopentyl pyrophosphate molecule so reactive? - '\ofi As s.\. 1 1 I r.udflll"'tt SrAQI 11'

4 17. DescribetheroleandpurposeofProstaglandins ldc~\ ll.ejk\"~"n 1 fo.in, bloool Ctotl'Y'cJ ~louet P'\.l.Jsl4.1\.t.l \==ever ~~~~~~~le has a higher energy density by weight-glycogen or ffn5 19. In the synthesis of glycogen, pyrophosphate (PPi) is hydrolyzed by water to form 2 phosphate groups. What is the purpose of this step? Is what other synthesis does this occur? -ro (;~-T.t.- ~5( ~ W\o\..{_ -l\,..tjl.td--t+,41.fovwa~~"~. f-r,.or ~t-o~ L.; Pt -r e'"""s! CO!AflRcl_ to enclo')jo"r\ll f" c.ltn.~ 20 B What enzyme was used for this step 21. A For the reaction below, what process is this from: a. Glycolysis b. Cholesterol synthesis c. Fatty acid biosynthesis 6!;> B-o:xidation e. Gluconeogenesis f. Pentose phosphate pathway 0 SCoA SCoA

5 22B What enzyme was used for this step? a. Phophofructokinase b. Lipolphosphatase c. AcetylCoA-Carboxylase d. Hydroxyl acetyl dehydrogenase [?Enoyl-coA hydratase - Ad~ I n3' H VJ 23 For the reaction below, draw in the arrow pushing mechanism of the next step. where 2,3 oxidosqualene is converted to the basic cholesterol structure Squalene 0 200e John Wla., 6 Son-, Inc. AU rlghu rearved. NADPH NADP+ \..._/ squalene epoxidase ~: 2,3-0xldosqualene mechanism Using the chart below answer Which direction is glycolysis (goin~ or up) 25. Which direction creates energy (rather than consumes)? Doi...\N). 1 Qt,tol~s, s 26. Which step is the allosteric inhibitor F2,6P important. - s v-el st~ F" P _, r I hbf> 27, Which enzyme does F2,6P inhibit? fvlattou. I;., ~pl,p!ph 11 ~s:.t.-

6 ncreased Glucagon secretion will promote which direction of this process own) -- G\ t...t..cjh.t o~s,s Glucose glucos:~:;;: }:x::nase phosphatase H20 ADP Glucose-6-phosphate ~ phosphoglucose isomerase 1 fructos:~~~uctos...a-ph"'f:: - phosphatase H20 ADP FructoM-1,6-blsphosphate n ldolase triose phosphate Dlhydroxyacetone Isomerase, Glyceraldehyde-3- phosphate phosphate Pi+ NAD+~~NAD+ +Pi glyceraldehyde-3-phosphate dehydrogenase NADH + H+ NADH + H+ 1,3-~sp~o h~ycerate ADP ~ADP phosphoglycerate kinase ATP ATP 3-PhosphOglycerate 1~ phosphoglycerat~ mutase 2-Phosphoglycerate n nolase CO,+GDP~!i::oacetate Pi+ADP pyruvate carboxylase ATP+C02 'v;~~:te kinase ~ ATP PJI'UVate o 2008 John Wiley & Sons. Inc. All rights reserved.

7 29. A For the reaction below, what process is this from: OH a. Glycolysis b. Glycogen synthesis c. Fatty acid biosynthiss d B-oxidation ~luconeogenesis f. Pentose phosphate pathway 30. Show the product of the reaction below: 0 OH ~ + R~ ~' SCoA acy }transferase o-c.; (tit))~rl> R E o-c.-tl Df'O 2-- i