Biochem 1

  1. What are the four basic biomolecules from which all living things are built?
    Amino acids, lipids, carbohydrates, nucleotides
  2. What is a hydrocarbon?
    A hydrophobic molecule containing only C and H
  3. What is an additional molecule bonded to the backbone of a molecule which contributes to the unique properties of that molecule?
    Functional group
  4. R-OH
  5. Image Upload 2
  6. Image Upload 4
  7. Image Upload 6
  8. R-NH2
  9. Image Upload 8
  10. R-SH
  11. Image Upload 10
  12. R-CH=CH-R'
  13. What are molecules with the same chemical formula but different bond arrangements?
  14. What type of isomers have different bonding patterns and properties?
  15. What type of isomers have similar properties and identical bonding patterns?
  16. What are the two subtypes of steroisomers and how do they differ?
    Optical isomers bend light in opposite directions (D-right, L-left). Geometric isomers differ in the arrangement of functional groups about a rigid bond (trans-opposite, cis-same)
  17. What is a racemic mixture?
    An equal mixture of D and L
  18. What is a chiral carbon? What is another name for it?
    A carbon with 4 different groups bonded to it and a nonsuperimposable mirror image. Also called an asymmetrical carbon.
  19. What are the mirror image pairs of a chiral carbon called?
  20. What form (D or L) are sugars and AA's found in the body?
    D-sugars, L-amino acids
  21. In what type of bond are the electrons shared equally?
  22. What type of bond involves an electronegative atom?
  23. What do you make from the polymerization of monosaccharides?
  24. What macromolecule is made from amino acids?
  25. What macromolecule is made from nucleotides?
    Nucleic acids
  26. What macromolecule is made from fatty acids?
  27. What are the 4 types of noncovalent bonds?
    Ionic, Hydrogen, Van der Waals, Hydrophobic
  28. What is the first law of thermodynamics?
    Energy cannot be created or destroyed, only transformed
  29. What is the second law of thermodynamics?
    Entropy (disorder) is constantly increasing
  30. What is free energy?
    Energy that can be used to do work (overcome entropy)
  31. What type of reaction produces free energy?
  32. What type of reaction uses energy?
  33. What are anabolic reactions? Do they tend to be exergonic or endergonic?
    Reactions that generate biomolecules, endergonic
  34. What are catabolic reactions? Do they tend to be exergonic or endergonic?
    Breakdown nutrients, exergonic
  35. DNA --> DNA
  36. DNA --> RNA
  37. RNA --> Protein
  38. What types of polar molecules can form hydrogen or ionic bonds with water and are therefore soluble in water?
  39. Nonpolar molecules that cannot H-bond with water are?
  40. What type of compounds have both polar and nonpolar parts?
  41. What is Kw? (I am looking for a number)
    1 X 10-14 M2
  42. What is Kw? (what values multiplied together)
    [H+] X [OH-]
  43. What is the concentration of H+ in neutral water?
    1 X 10-7 M
  44. What is the equation for determining pH?
  45. An acidic solution would have a pH _____?
    less than 7
  46. An alkaline solution would have a pH ____?
    More than 7
  47. How do buffers affect pH?
    They resist pH change (they keep pH close to constant)
  48. What equation is used to determin Ka?
    Image Upload 12
  49. Will a strong acid have a high or low Ka? pKa?
    high Ka, low pKa
  50. What is an acid?
    A molecule that donates a proton to water
  51. What is a base?
    A molecule that accepts a proton from water
  52. What is a buffer made from?
    A conjugate acid-base pair (A weak acid and its conjugate base)
  53. What equation is used to describe the titration curve of an acid? What is the name of this equation?
    • Image Upload 14
    • Henderson-Hasselbach equation
  54. What is the phosphate buffer system used for?
    To maintain the pH of the cytoplasm between 6.4 and 7.4
  55. What is the bicarbonate buffer system used for?
    To maintain the blood pH between 7.35 and 7.45
  56. What enzyme combines carbon dioxide and water to make carbonic acid?
    Carbonic anhydrase
  57. How does the body use the bicarbonate buffer system to correct a change in pH?
    If the blood becomes acidic we hyperventilate to get rid of excess CO2 and use up H+ to make more CO2 and water. If the body is too basic the kidney removes bicarbonate ions so that more H+ is made.
  58. What is the isoelectric pH?
    The pH at which the net charge of the solution is zero
  59. What is the composition of an amino acid?
    alpha-carbon attached to an amino, carboxyl, H and side chain (R)
  60. Gly
  61. Ala
  62. Val
  63. Leu
  64. Ile
  65. Phe
  66. Trp
  67. Met
  68. Cys
  69. Pro
  70. Which AA is achiral?
  71. Which AA's are branched?
    Val, Leu, Ile
  72. Which AA's are aromatic?
    Phe, Trp, Tyr
  73. Which AA is the largest?
  74. Which AA's contain sulfur?
    Met, Cys
  75. Which AA readily forms disulfide bonds?
  76. Which AA is cyclic?
  77. Which AA contains an imino group?
  78. Which AA has the R group: H?
  79. Which AA has the R group: CH3?
  80. Which AA has the R group: CH - (CH3)2?
  81. Which AA has the R group: CH - CH - (CH3)2?
  82. Image Upload 16
  83. Image Upload 18
  84. Image Upload 20
  85. Which AA has the R group: CH2-CH2-S-CH3
  86. Which AA has the R group: CH - SH
  87. Image Upload 22
  88. Which AA has the R group: CH2 - OH
  89. Image Upload 24
  90. Image Upload 26
  91. Image Upload 28
  92. Image Upload 30
  93. Which AA has the R group: CH2 - COOH
  94. Which AA has the R group: CH2 - CH2 - COOH
  95. Which AA has the R group: (CH2)4 - NH3+
  96. Which AA has the R group: (CH2)3 - NH - C - (NH2)2
  97. Image Upload 32
  98. Which AA's are uncharged and polar?
    Ser, Thr, Tyr, Asn, Gln
  99. Which AA's are charged, acidic?
    Asp, Glu
  100. Which AA's are charged, basic?
    Lys, Arg, His
  101. Ser
  102. Thr
  103. Tyr
  104. Asn
  105. Gln
  106. Asp
    Aspartate/Aspartic acid
  107. Glu
    Glutamate/glutamic acid
  108. Lys
  109. Arg
  110. His
  111. What is a zwitterion?
    A neutral molecule with both a postive and negative charge.
  112. Is a carboxyl group an acid or base?
    Weak acid
  113. Is an amino group an acid or base?
    weak base
  114. What is an amphoteric electrolyte?
    A molecule capable of having both a postive and negative charge but not necessarily at the same time
  115. What are the non-standard AA's and why are they called non-standard?
    Citrulline, ornithine, hydroxyproline, desmosine, they are not used to make protein
  116. Which non-standard AA's are part of the urea cycle?
    Citrulline and ornithine
  117. Which non-standard AA is in collagen?
  118. Which non-standard AA is found in elastin?
  119. Which of the AA's are essential?
    Val, Met, Leu, Trp, Ile, His, Lys, Thr, Phe
  120. Which AA is essential only in youth?
  121. How many pKa's would an AA with no ionizable side chains have?
  122. How many pKa's would an AA with one ionizable side chains have?
  123. What is the isoelectric point?
    pH at which the net charge of an AA is zero
  124. What type of reaction creates peptide bonds?
    A condensation reaction between the carboxyl on one AA and the amino on another AA
  125. How many AA's are in a peptide chain containing 10 peptide bonds?
  126. What are two ways peptide bonds can be hydrolyzed?
    6M HCl or proteolytic enzymes (protease, peptidase)
  127. What factors can affect the structure of a peptide?
    AA sequence, temp., pH, rigidity of the peptide bonds
  128. What is the primary structure of a peptide?
    The sequence of AAs listed from N-terminus to C-terminus
  129. What are the two main types of secondary structure of AA's?
    alpha-helix and beta-sheets
  130. What interactions hold the secondary structure together?
    Hydrogen bonds
  131. Which secondary structure can involve parts of multiple peptide chains?
    beta-sheets (antiparallel and parallel)
  132. What can lead to the formation of Beta-bends?
    4 or more charged or bulky AA's or proline
  133. What tertiary structure is the most energetically favorable?
  134. What 5 interaction contribute to tertiary structure?
    Disulfide bridges, H-bonds, electrostatic interactions between charged R groups, van der Waals, hydrophobic
  135. What is quaternary structure of a protein?
    the combining of multiple polypeptide chains
  136. What is denaturation?
    The loss of secondary and tertiary structure without breaking peptide bonds
  137. What is renaturation?
    The correct refolding of a denatured protein (note: few proteins can do this)
  138. What is an example of a protein that can renature?
    Ribonuclease A
  139. What is the resulting molecule called when a protein is joined with a lipid?
  140. What is the resulting molecule called when a protein is joined with a carbohydrate?
  141. What is the resulting molecule called when a protein is joined with a nucleotide?
  142. What is the resulting molecule called when a protein is joined with a heme?
  143. What secondary structures make up fibrous proteins?
    Either alpha-helix or beta-sheets but not both
  144. Are fibrous proteins soluble in water? What is their main function?
    Insoluble, structure
  145. What fibrous protein is found in hair, nails, skin, wool?
  146. What secondary structure is found in alpha-keratin?
  147. What type of bonds are prominent in alpha-keratin?
    Disulfide bridges
  148. What fibrous protein is rish in Cys and hydrophobic AA's?
  149. What do alpha-keratin fibers wound together create?
  150. What fibrous protein is found in spider web and silk?
  151. What secondary structure is found in beta-keratin?
    antiparallel beta-sheets
  152. What type of bond is prominent in beta-keratin?
    hydrogen bonds
  153. What fibrous protein is soft but has high tensile strength due to its compact (repeating Ala-Gly) structure?
  154. What fibrous protein is found in connective tissue?
  155. What secondary structure is found in collagen?
    beta-helix (left-handed)
  156. What type of bonds are prominent in collagen?
    Lys or Leu bonds
  157. What fibrous protein has a repeating Gly-X-Pro structure?
  158. What vitamin is required for the hydroxylation of proline in collagen?
    vitamin c
  159. What fibrous protein is one third Gly? *Board Q
  160. What 3 AA's can be hydroxylated by vitamin C?
    Pro, lys, Ala
  161. What structue is elasin found in?
    elastic CT
  162. What secondary structures are found in elastin?
    alpha-helix and lys islands
  163. What is the composition of desmosine?
    4 lys and 2 or more tropoelastin
  164. What fibrous protein has the ability to stretch in all planes?
  165. What secondary structure will proline disrupt?
    alpha-helix (note: it will not disrupt a beta-sheet
  166. What secondary structures are found in globular proteins?
    alpha-helices and beta-sheets
  167. Are globular proteins water soluble? What are their functions?
    they are water soluble, enzymes, transporters, storage, motilitly, immune, regulatory (every function except structure)
  168. What are two prominent examples of globular proteins?
    Myoglobin and hemoglobin
  169. What level protein is myoglobin and where is it found?
    tertiary, skeletal and cardiac muscle
  170. What is the structure of myoglobin?
    8 alpha-helices interupted by proline (beta-bends) with a heme (iron) in the center
  171. What is the purpose of myoglobin?
    Temporary oxygen storage for muscle (takes oxygen from hemoglobin)
  172. Is the binding affinity for myoglobin higher or lower than for hemoglobin? What shape is the binding affinity curve?
    higher, hyperbolic
  173. What level protein is hemoglobin? What is its structure?
    quartenary, 4 poly peptide subunits (similar to 4 myoglobins) - 2 alpha and 2 beta globulins, each containing a heme group
  174. What are two factors that can decrease hemoglobins affinity for oxygen?
    a decrease in pH (from lactic acid) or an increase in 2,3-BPG
  175. Does fetal hemoglobin have a higher or lower binding affinity for oxygen than adult hemoglobin?
  176. What is cooperativity? (seen in hemoglobin)
    the binding of one oxygen triggers a conformational change so that the other 3 oxygens can bind more easily
  177. What defect is present in elhers-danlos syndrome?
    a defect in the metabolism of collagen I, III, IV
  178. What are the most common symptoms of elhers-danlos syndrome?
    vascular issues, fragile/stretchy skin, loose joints
  179. What defect is present in osteogenesis imperfecta?
    bulky side chains replace glycine in collagen to triple-helical conformation (tropocollagen) cannot form
  180. What is another name for osteogenesis imperfecta? What is the main symtom of OI?
    brittle bone syndrome, bones bend and fracture
  181. What is another name for sickle cell disease?
    hemoglobin S disease
  182. What defect is present in sickle cell anemia?
    val replaces glu at position 6 of the beta-globulins in hemoglobin creating an unstable quarternary structure
  183. What will low oxygen trigger in an individual with sickle cell ds?
    the subunits of hemoglobin will become linear, the RBCs will distend and thier lifespan will decrease to less than 20 days
  184. What race and age of people are most commonly affected by sickle cell ds?
    African-american children
  185. What is alpha-antitrypsin?
    a protease inhibitor that protects the lungs and liver
  186. What are the two main symptoms of an alpha-antitrypsin (AAT) deficiency?
    emphysema and cirrhosis
  187. What is sanger's method?
    an AA sequencing method of removing the N-terminal of the peptide as a dinitrophenyl (DNP) by adding 1-fluoro-2,4-dinitrobenzene
  188. What enzyme will remove the C-terminal of a peptide?
  189. What enzyme will cut at lys and arg?
  190. What two enzymes cut at the aromatics (phe, trp, tyr)?
    chymotrypsin and pepsin
  191. What side of the AA do trypsin, chymotrypsin and pepsin cut from?
  192. What do enzymes do? What do enzymes not do?
    They increase the rate of a reaction by lowering the activation energy. They do not affect the equilibrium of the reaction.
  193. What do lyases do?
    they add or remove atoms from a double bond
  194. What do ligases do?
    combine molecules using ATP
  195. What is the active site of an enzyme?
    The site where substrate binds to the enzyme
  196. Where does a competitve inhibitor bind? Will adding more substrate reverse its effects?
    Active site, yes
  197. Where does a noncompetitive inhibitor bind? Will adding more substrate reverse its effects?
    A site separate from the binding site, no
  198. What are the two types of cofactors?
    metal and organic
  199. Which type of cofactor are coenzymes and what do they do?
    they are organic, they provide a functional group
  200. What does FAD stand for? *Board Q
    Flavin adenine dinucleotide
  201. What does NAD stand for? *Board Q
    Nicotinamide adenine dinucleotide
  202. What coenzyme is formed from B2? *Board Q
  203. What is the name of B2? *Board Q
  204. What chemical group is transferred by FAD? *Board Q
  205. What coenzyme comes from B3? *Board Q
  206. What is the name of B3? *Board Q
    Niacin/nicotinic acid
  207. What chemical group is transferred by NAD? *Board Q
    hydride (H-)
  208. What coenzyme comes from B5? *Board Q
    Coenzyme A
  209. What is the name of B5? *Board Q
    Pantothenic acid
  210. What chemical group is transferred by coenzyme A? *Board Q
    Acyl group
  211. What coenzyme comes form B6? *Board Q
    Pyridoxal phosphate
  212. What is the name of B6? *Board Q
  213. What chemical group is transferred by pyridoxal phosphate? *Board Q
  214. What conezyme comes for B1? *Board Q
    Thiamin pyrophosphate
  215. What is the name of B1? *Board Q
  216. What chemical group is transferred by thiamin pyrophosphate (TPP)? *Board Q
  217. What coenzyme is formed from B7? *Board Q
  218. What is the name of B7? *Board Q
  219. What coenzyme is the same as the vitamin it comes from? *Board Q
  220. What chemical group is transferred by Biotin? *Board Q
  221. What conezyme is formed from B9? *Board Q
    Tetrahydrofolate (THF)
  222. What is the name of B9? *Board Q
    Folic acid
  223. Waht chemical group is transferred by THF? *Board Q
    one carbon (methyl) group
  224. What is the activation energy?
    The energy required to reach the transition state
  225. How does an enzyme decrease the activation energy of a reaction?
    When substrate and enzyme bind a conformational change occurs in the substrate so that the activation energy is lowered
  226. What is the rate limiting step?
    the step with the highest activation energy (slowest)
  227. Michaelis-menton equation
    Image Upload 34
  228. Would an enzyme with a high affinity for its substrate have a high or low Km?
  229. When Vo is (1/2)Vmax, what does Km = ?
  230. Lineweaver-Burke equation
    Image Upload 36
  231. What does the slope of the lineweaver-burke plot equal?
  232. What is the y-intercept of the lineweaver-burke plot?
  233. What is the x-intercept of the lineweaver-burke plot?
  234. What do irreversible inhibitors do?
    bind permanently, prevent the reaction from occuring
  235. How do reversible competitive inhibitors affect Km and Vmax?
    increase, no effect
  236. How do reversible noncompetitive inhibitors affect Km and Vmax?
    no effect, decrease
  237. What are the three types of enzyme regulation?
    Allosteric (reversible binding of an activator or inhibitor), covalent modification (ex. phosphorylation by kinase or removal of phosphate by phosphatase), activation by proteolytic cleavage of a zymogen (inactive precursor - short peptide blocks active site)
  238. What is the zymogen of pepsin? What is it secreted by?
    Pepsinogen, stomach
  239. What are the three zymogens secreted by the pancrease and what are their active forms?
    chymotrypsinogen (chymotrypsin), trypsinogen (trypsin), procarboxypeptidase (carboxypeptidase)
  240. What are isozymes?
    Groups of enzymes that catalyze the same reaction
  241. What two isozymes convert glucose to glucose-6-phosphate? Where does each primarily act?
    hexokinase (muscles, RBCs), glucokinase (liver only)
  242. What are 3 types of lipids composed of fatty acids?
    Triacylglycerols (triglycerides), phosphoacylglycerol, spingolipids
  243. Are triacylglycerols polar or non-polar? What is their function?
    Non-polar, fat storage
  244. Are phosphoacylglycerol and spingolipids polar or non-polar? What is their function?
    polar, they make up cell membranes
  245. What group of lipids is based on a ring structure? What are the three main examples within this group?
    Non-saponifiable (cholesterol, steroids, hormones)
  246. What are fatty acids? Are they polar or non-polar?
    long hydrocarbon chains with a carboxylic acid on the end, they are amphipathic (have both polar and nonpolar parts)
  247. What does saturated mean (when referring to fatty acids)?
    there are no double bonds (saturated with hydrogen)
  248. What type of double bonds (cis or trans) are found in naturally occuring unsaturated fatty acids?
  249. What are three differences between saturated and unsaturated fatty acids?
    Saturated fatty acids pack closer together, they have a higher melting temp., they are less fluid
  250. How are fatty acids described (what numbers are used, how are they written)?
    # of carbons:# of double bonds(delta)position of double bonds
  251. What is the omega end? How is it used to name fatty acids?
    The omega carbon is the carbon furtherest from the carboxyl end. Fatty acids can be named by the position of the double bond closests to the omega carbon (ex. an omega 1 fatty acid would have a double bond between the omega carbon and the carbon adjacent to it)
  252. What are the three essential fatty acids?
    Arachidonic acid, linoleic acid and alpha-linolenic acid
  253. Which two omega 6 fatty acids are essential? How many carbons and double bonds do they have?
    linoleic acid, 18:3, arachidonic acid 20:4
  254. Which omega 3 is essential? How many carbons and double bonds does it have?
    alpha-linolenic, 18:3
  255. What are triacylglycerols made of?
    glycerol and 3 fatty acids
  256. Where do oils come from? Are they saturated or unsaturated? What is the exception?
    plants, all unsaturated except cocunut oil which is saturated
  257. Where do fats come from? Saturated or unsaturated?
    animals, saturated
  258. What is olestra? What vitamins does it deplete in the body?
    fat substitute which is not absorbed by the body, depletes A,D,E,K
  259. What does lipase do?
    Break down triglycerides in the adipocytes and the intestines
  260. What is saponification?
    Making soap by adding triglycerides, NaOH and heat
  261. How do phosphoacylglycerols (phospholipids, phosphoglycerides) differ from triacylglycerides?
    An ester replaces one fatty acid
  262. Where is phospholipase A2 found? What does it do? *Board Q
    snakes, hydrolyzes the second fatty acid in triacylglycerides --> dissolves membranes of RBCs
  263. What is a sphinolipid?
    sphingosine + 1 fatty acid + O-X
  264. What accumulates in Tay-Sachs? What 3 places does it accumulate? What deficiency causes this? What is the result of Tay-Sachs?
    gangliosides (oligosaccharides) accumulate in nerve cells, brain and spleen causing death, defeciency in hexosaminidase A
  265. Niemann-Pick is a deficiency in what? What are the symptoms?
    sphingomyelinase (phosphocholine) which makes up myelin, mental retardation and death
  266. What is Gaucher ds a deficiency in? What accumulates? What are the 3 symptoms?
    glucocerebrosidase deficient, glucocerebrosides (sugar) accumulates causing an enlarged liver and spleen, bone pain, anemia
  267. What 4 lipids are found in biological membranes?
    phospholipids, glycosphingolipids, sphingolipids, cholesterol
  268. What is a uniporter?
    A transport protein in the membrane that only transports one molecule
  269. What is a symporter?
    A transport protein in the membrane that transports two molecules in the same direction
  270. What is an antiporter?
    A transport protein in the membrane that transports two molecules in opposite directions
  271. What is facilitated diffusion?
    Transport of molecules by membrane proteins without the use of energy (from high to low concentration)
  272. What is active transport? What is the difference between primary and secondary?
    Transport from low to high concentration (requires energy), in primary the energy comes from ATP, in secondary the energy comes from simultaneously transporting another molecule from high to low concentration
  273. What is an example of primary active transport?
    Na-K pump (3Na out, 2K in)
  274. What is an example of secondary active transport?
    Na-glucose pump (glucose moves high to low while Na moves low to high)
  275. What is the general formula for carbohydrates?
  276. What type of sugar is glyceraldehyde?
  277. What type of sugar is dihydroxyacetone?
  278. What type of sugar is ribose?
  279. What type of sugar is glucose?
  280. What type of sugar is galactose?
  281. What type of sugar is fructose?
  282. What 3 ketones exhaled by diabetics?
    Acetone, acetoacetate, beta-hydroxybutyrate
  283. What does "ul" in the name of a sugar indicate?
    It is a ketose
  284. What monosaccharide does not have at least one chiral center?
  285. What is the number of chiral centers in an aldose?
    # of C's - 2
  286. What is the # of stereoisomers of a monosaccharide?
    2# of chiral centers
  287. What chiral carbon is the D or L of a sugar based on?
    the one furthest from the carbonyl
  288. What are epimers?
    Sugars that differ around only 1 chiral carbon
  289. What is an example of an epimer?
    Glucose and Galactose
  290. What type of ring do aldoses form?
    pyranoses (5-membered)
  291. What are two common monosaccharides tha form pyranose rings?
    Glucose, galactose
  292. What type of ring do most ketoses form?
    furanose (5-membered)
  293. What are two common furanoses?
    Ribose, fructose
  294. What is the anomeric carbon of a monosaccharide ring? What does it form?
    Carbon that was part of the carbonyl group, forms the reducing end of the sugar
  295. What is the structure of maltose? Is it reducing?
    glucose and glucose form a (1,4)-o-glycosidic bond, reducing
  296. What is the structure of trehalose? Is it reducing?
    glucose and glucose form a (1,1)-o-glycosidic bond, non-reducing
  297. What is the structure of lactose? Is it reducing?
    glucose and galactose form a (1,4) bond, reducing
  298. What is the structure of sucrose? Is it reducing?
    fructose and glucose form a (1,2) bond, non-reducing
  299. What are 3 common examples of homopolysaccharides?
    Starch, glycogen and cellulose
  300. Is amylose branched? What type of O-glycosidic bonds does it have?
    No, alpha1-4 only
  301. Is amylopectin branched? What type of O-glycosidic bonds does it have?
    highly branched, alpha1-4 and alpha1-6
  302. Is glycogen branched? What type of O-glycosidic bonds does it have?
    Even more branched than amylopectin, alpha1-4 and 1-6
  303. What are the two types of starch and where do they come from?
    amylose and amylopectin, from plants
  304. Where is glycogen found?
  305. What type of O-glycosidic bonds does cellulose have? Where is it found? Can we digest it?
    beta1-4, plant (structural), no
  306. Where are peptidoglycans found?
    Bacterial cell walls
  307. Where are glycoproteins found?
    plasma membranes, hormones, antibodies
  308. What is the difference between an enantiomer and an epimer?
    An enantiomer is the mirror image (all of the chiral carbons have groups switched), an epimer has groups switched at only one carbon
  309. What does UDP do to glucose? Where does this occur?
    Cytoplasm, UDP activates it and marks it for polymerization (add to glycogen)
  310. Glucose is converted to G6P by which enzymes and what coenzyme?
    Hexokinase (all other tissues), Glucokinase (liver), ATP
  311. Which has a higher Km hexokinase or glucokinase?
  312. What enzyme converts G6P to G1P?
  313. Where does UDP-glucose to begin a glycogen chain?
    Tyr on glycogenin
  314. What enzyme creates alpha1-4-O-glycosidic bonds?
    glycogen synthetase
  315. What enzyme creates alpha1-6-O-glycosidic bonds?
    glycogen branching enzyme
  316. Where is glucagon made?
    alpha-cells of pancreas
  317. What does glucagon do?
    decrease blood sugar by decreasing glycogen synthesis in the liver and increasing glycogen breakdown
  318. Where is epinephrine made?
    adrenal medulla
  319. What does epinephrine do?
    Mobilize energy by decreasing glycogen synthesis in muscle and increasing glycogen breakdown
  320. Where is insulin made?
    beta-cells of pancreas
  321. What does insulin do?
    decrease blood sugar by increase synthesis and decrease breakdown of glycogen
  322. What pathway does glucagon/epinephrine? (4 steps)
    --> adenylate cyclase --> cAMP --> Protein kinase --> activates glycogen phosphorylase (breaksdown glycogen)/deactivates glycogen sythase
  323. Hypoglycemia is an issue with what organ?
  324. What results from defective glycogen synthase?
    failure to thrive, hypoglycemia, no glycogen
  325. What results from a deficiency in G6Phosphatase?
    Von Gierke's disease
  326. What results from a deficiency in phosphorlyase or debranching enzyme?
  327. What are the 3 parts of a nucleotide?
    nitrogenous base, pentose sugar, phospholipid
  328. What bases are present in RNA?
    Adenine, Guanine, Cytosine, Uracil
  329. What bases are present in DNA?
    Adenine, Guanine, Cytosine, Thymine
  330. Which bases are purines?
    A, G
  331. Which bases are pyrimidines?
  332. What are the 2 parts of a nucleoside?
    deoxyribose or ribose sugar and a base
  333. How are nucleotides linked together?
    The 3'C of one forms a phosphodiester bond with the 5'C of the next
  334. What is the primary strucuture of nucleic acids? How are they arranged?
    line of nucleotides arranged into triplets called codons
  335. What is the secondary structure of DNA?
    Right handed, double antiparallel helix, A with T, G with C, bases H-bonded in, pentose-phosphate backbone
  336. How many residues are in a turn of DNA?
  337. What is the secondary structure of RNA?
    Can be single or double stranded, A with U, C with G
  338. What is the tertiary structure of DNA?
  339. What is the tertiary structure of RNA?
    Varies (ex. rRNA is ribosome)
  340. What does mRNA do?
    bring info. from nucleus to ribosome
  341. What does tRNA do?
    Decodes the genetic code, brings relevant AA
  342. What is denaturation of a nucleic acid?
    breaking the H-bonds without breaking the phosphodiester bonds
  343. What can cause denaturation of a nucleic acid?
    Heat, high pH
  344. What is hybridization?
    When two single-stranded nucleic acids have a region of complementarity and H-bond
  345. What are 4 causes of DNA damage?
    aging (deamination, oxidation), UV light (thymine-thymine dimer), X-ray (fragments bases), nitrites (deaminate bases)
  346. What is the 2nd messenger in the pathway activated by glucagon/epinephrine?
  347. What 3 coenzymes are derived from adenine?
    FAD, NAD, CoA
Card Set
Biochem 1
These are flashcards for Biochem 1 at sherman and study for nbce