bc #6

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bc #6
2012-08-08 00:54:18

bc 6
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  1. Hormones (The primary messenger) arrives at the exterior of a cell to stimulate the snythesis of _________ (The secondary messenger) inside the cell.
     cyclic AMP
  2. The two main hormones that can be primary messengers are...
    adrenalin (epinephrine) and glucagon
  3. The binding sites for the hormones in on the _____ of the cell, facing the _________.
    • exterior
    • bloodstream
  4. The hormone receptor binds to another protesin in the membrane called the....
  5. The active form of glycogen phosphorylase kinase is the
    "a" form with phosphate attached
  6. Adenylate cyclase is located in the ___ , facing the ______ of the cell.
    • plasma membrane,
    • inside
  7. If the Phosphorylation and Dephosphorylation cascades are abbreviated PhosC and DephosC respectively, then the cAMP-dependent many protein kinase
    turns on PhosC and turns off DephosC
  8. For a protein that has a "b" form, that form always is the ___ form.
  9. Caffeine is an inhibitor of ___ .
    cyclic nucleotide phosphodiestersae
  10. Comparing the phosphorylation and dephosphorylation cascades, the example with more steps in the sequence is the ___ cascade. Having more steps is ___ for responding to an emergency.
    • phosphorylation
    • better
  11. The reaction (cAMP -> AMP) is catalyzed by
    nucleoTide phosphoDIesterase
  12. The letter "G" in the name "G protein" stands for ___ .
  13. The direct function of G protein itself is to
    activate adenylate cyclase
  14. The dephosphorylation cascade is initiated by increases in the concentration of ___ .
  15. The many-protein kinase (protein kinase A) which initiates the phosphorylation cascade is itself activated when it binds is..
  16. The enzyme catalyzing the opposite effects of the cAMP-dependent many protein kinase is the
    many phosphoprotein phosphatase
  17. Phosphorylation of enzymes (activates or inhibits enzymes?)
    either of the above, depending on the specific example
  18. Adrenalin and glucagon lead to similar effects in liver because they both...
    generate the same secondary messenger
  19. The substrate of adenylate cyclase is
  20. One direct substrate of the cAMP-dependent many-protein kinase (protein kinase A) is ___ .
    glycogen phosphorylase kinase
  21. Adrenalin initiates a series of reactions which inhibits glycolysis step 10 in the ___ .
  22. The cycle by which glucose is converted into lactate in muscles, then converted back into glucose in the liver, and finally transported back to the muscles is the ___ cycle.
  23. The regulated steps in glycolysis are all strongly ________.
    are all strongly downhill (in the glycolysis direction)
  24. An example of an enzyme which is inhibited by its own product is ___ .
    muscle hexokinase
  25. Organ(s) which contain the enzyme for bypass III of gluconeogenesis include the ___ .
  26. The regulated steps in glycolysis are steps ___ .
    1,3, and 10
  27. The concentration of glucose in the blood in a normal healthy human being is ___ mM.
  28. Insulin causes GLUT4 transporters in muscle cells to move from the ___ .
    cytoplasm to the plasma membrane
  29. The reaction pyruvate -> lactate includes a ___ conversion.
    C=O -> H-C-OH
  30. When S-init is much less than Km, the Michaelis-Menten relationship simplifies to the form of a ___.
    sloped straight line which intersects the origin
  31. Muscles lack receptors for ___ .
  32. In muscle hexokinase, its Km is much ___ than the [substrate], so its active site is nearly always ___ suibstrate
    smaller; filled with
  33. The organ which is responsible for maintaining a relatively constant level of glucose in the blood is the ___ .
  34. An organ which uses glucose but not fatty acids as a fuel is the ___ .
  35. An example of an enzyme which is inactivated by phosphorylation is ___ .
    liver pyruvate kinase
  36. The type of glucose transporter that is regulated by endocytosis and exocytosis occurs in the _____.
  37. For an enzyme or transporter to be under substrate-level control, its Km should be ___ the typical physiological concentration of that substrate.
    greater than
  38. Diabetics have blood glucose concentrations which are too
  39. Caffeine is bad for the diabetic because it ___ the blood glucose level because it ___ the enzyme which catalyzes cAMP -> AMP.
    increases (glucose) ; inhibits (cAMP -> AMP)
  40. Diabetes leads to circulatory problems by
    stimulating cell proliferation in artery walls caused by leukotrienes secreted by macrophages responding to glycosylated collage AND

    inhibiting recycling of serum lipoproteins by receptors in the liver's outer membrane because the lipoproteins are glycosylated
  41. The official death rate attributed to diabetes is underestimated, because diabetes also indirectly contributes to deaths which have been listed as being caused by
    heart attacks
  42. Desensitization refers to
    a lowering of the concentration of insulin receptors
  43. Desensitization is usually associated with a _____ of insulin in the blood
    an excess of insulin in the blood
  44. The glycosylation of blood vessel proteins occurs...
    without an enzyme in all people, but faster in people with high blood glucose levels
  45. Which of the following is NOT a long-range complication of diabetics?
    amenia (loss of blood cells)
  46. The best meal plan for the diabetic is toThe best meal plan for the diabetic is to
    eat six small sized meals spaced about 2.5 to 3 hrs apart
  47. The primary harmful effect of diabetes glucose effects in the blood is
    damage to blood vessels
  48. The most reliable test for diabetes is the concentration of
    glycosylated Hb at any time during the day
  49. Stress is bad for the diabetic because it activates the adrenalin (epinephrine) cascade which
    breaks down glycogen into glucose
  50. There are two types of diabetes. Type II is characterized by
    adult onset and decreased sensitivity to the supply of insulin
  51. the enzyme which is capable of conerting ATP into cAMP is on the _____ side of the plasma membrane with it's active site facing the _________.
    • inner
    • cytoplasm
  52. when a hormone arrives on the scene in the bloodstream it causes a _______ change in the receptor which cuases a _______ change in the g-protein subunits.
    • confomational
    • confomational
  53. the conformational chaing in the g-protein subunits causes G-alpha to release ____ into the cytoplasm and bind ____ in its place. also replacing G-Alpha with ________
    • GDP
    • GTP
    • G-alpha w/ GTP bound
  54. When adenylate cyclase catalyzes the reaction that converst ATP into cAMP _________ is released
    Inorganic pyrophosphate
  55. The adenylate cyclase reaction is very favorable because
    it tries to replanish the depleted PPi
  56. Adenylate =?
  57. what two hormones cause the same effect in liver cells (stimulating breakdown of glycogen into glucose)?
    adrenalin and glucagon
  58. both the adrenalin and glucagon receptor bind to _____ which in turn activate _______.
    • G proteins
    • adenylate cyclase
  59. when the receptors bind its respective hormone,  the receptor changes _______ and affects the G protein in a way that will indirectly change the conformation of _______, causing it to activate.
    • conformation
    • adenylate cyclase
  60. The secondary messenger cAMP is produced either by binding...
    • adrenalin to the liver cell
    • glucagon to the liver cell
  61. enzyme 3 = ?
    glycogen phosphorylase
  62. enzyme 4=?
    glycogen synthase
  63. the active form is called
    the "a" form
  64. the inactive form is called
    the "b" form
  65. enzyme 2=?
    glycogen phosphrylase kinase
  66. Enzyme 2 activates enzyme 3 by...
    removing a phosphate from ATP and pasting it onto enzyme 2
  67. enzyme 1 =?
    cAMP-dependent many proteins kinase
  68. Kinases are...
    things that remove phosphate groups from something and paste it somewhere else.
  69. enzyme 2 kinase name=?
    glycogen phosphorylase kinase kinase
  70. the inactive form of enzyme 1 is a tetramer containing...
    two catalytic subunits (C) and two regulatory subunits (R)
  71. the inactivated enzyme 1 dissociates into..
    2 monomeric C catalytic subunits and a single R2 dimer
  72. how many cAMPs are bound to the inactivated enzyme 1 dimer?
  73. in the first amplification, it take ___ bound cAMP to convert one cAMP-dependent many-protein kinase coomplex into the active ____ form.
    • 4
    • 2C's
  74. amplification equation
    5C2R2 + 20(cAMP)   ->  10C   +   5R2(cAMP)4
  75. 20 cAMP molecules created by one activated adenylate cyclase enzyme molecule are depicted by turning on...
    10 cAMP-dependent many-protein kinase subunits
  76. additional  ___x amplifications are proposed for each subsequent step in the cascade.
  77. when adrenal gland stop secreting adrenalin, the concentration of _______ arriving at the liver is decreased.
  78. 3',5'-cAMP is broken down to 5'-AMP by cleaving ...
    the ester bond between the phosphate group and the hydroxyl group
  79. cAMP can build up faster than it is broken down as long as...
    hormones are bound to the outside of the cell
  80. One hormones stop binding to the cell there ultimately will be a net breakdown of...
  81. the enzyme catalyzing cAMP breakdown is called
    cyclic nucleotide phosphodiesterase
  82. a drug whose ring structure resembles the adenine sidechain of cyclic AMP is...
  83. _______ can function as a competitive inhibitor of cyclic nucleotide phosphodiesterase
  84. Levels of cAMP are arrtificially _____ in the liver cells of a coffee drinker
  85. the feeling of "high energy" after you drink a cup of coffee is generated by artificially high amounts of ______ being released by the liver into the bloodstream.
  86. ______ produces the opposite effects of adrenalina or glucagon.
  87. the purpose of insulin is to...
    stimulate liver to take excess glucose out of the bloodstream and to store that in the form of glycogen.
  88. insulin stimulates a ______ cascade
  89. glycogen synthase's activated from is .... (phosphory.ated or dephosphorylated)
  90. enzyme 5=?
    "many-phosphoproteins phosphatase"
  91. insulin stimulates an increase in the active form of _______ inside the cell.
    enzyme 5
  92. enzyme 5 can be regulated by binding to....
    an inhibitor ( a phosphorylated protein)
  93. the inhibitor that binds to enzyme 5 is called....
    phosphoprotein phosphatase inhibitor
  94. enzyme 1 turns on enzyme ___ in the phosphorylation cascade and turns off enzyme ___ in the dephosphorylation cascade.
    • 2
    • 4
  95. enzyme 1 indirectly turns off enzyme 5 in the dephosphorylation cascade by...
    converting the phosphoprotein phosphatase inhibitor into its active phosphorylated form, which binds to enxyme 5 and inactivates it.
  96. enzyme 5 turns on enzyme ___ in the dephosphorylation cascade but also turns off enzymes ___ and ____ in the phosphorlyation cascadae.
    • 4
    • 2 & 3
  97. the phosphorlyation and dephosphorlyation cascades are in a delicate competitive balance which respoonds to relative concentrations of _______, ______ and _______ in the bloodstream.
    adrenalin, insulin and glucagon
  98. the _____ has the special function of "buffering" the level of glucose in the bloodstream, trying to maintain that concentration at a ___ mM level.
    • Liver
    • 5
  99. Skeletal muscle uses glucose and fats to manufacture _____ for use in muscle contraction under both aerobic and anaerboic conditions.
  100. Liver cells have receptors for each hormone in their ________.
    outer plasma membrane
  101. Muscle cells have receptors for insulin so that they can build up...
    their small supply of glycogen when appropriate
  102. muscle cells have receptors for adrenalin so they can convert...
    glycogen back into glucose during an emergency
  103. Muscles do not have receptors for....
  104. Bypass III (gluconeogensis) occurs in the _____ and not the _____.
    • liver
    • muscles
  105. muscles do not express the gene for _________, because it the enzyme catalyzes bypass III.
  106. muscle cells do contain the DNA gene which codes for that enzyme since all cells of a human being are derived from...
    the same original fertilized egg cell.
  107. the gene for the phosphatse is ________ in muscle cells.
    not turned on.
  108. liver and muscle cells both have receptors for...
  109. Muscles need _______ to be stimulated
  110. the liver needs ______ to be stimulated.
  111. the liver needs _____ to be inhibited.
  112. different enzyme forms are called = ?
    iso-enzymes or isozymes
  113. the human body has at least ___ genes coding for pyruvate kinase (step 10 of glycolysis)
  114. in liver, the gene that is expressed produces an isozyme that is capable of being phosphorylated by the _____.
    cAMP-dependent "many-protein" kinase
  115. the isozyme of pyruvate kinase which is expressed in muslce cells is not capable of being phosphorylated because...
    of differences in the presence of ser and thr sidechains in its sequence, or their environments in the tertiary structure.
  116. muscle pyruvate kinase is _________ in the presence of adrenalin
    not inhibited
  117. liver pyruvate kinase is _______ in the presence of adrenalin.
  118. step 1 of glycolysis is....
    conversion of glucose into G6P
  119. in muscles, the gene that is expressed in step 1 of glycolysis produces the enzyme called.....
  120. in liver, the gene that is expressed in step 1 of glycolysis produces the enyme called...
  121. the best design for the liver enzyme is to make step 1 of glycolysis is directly
    proportional to the level of glucose in the blood
  122. making the velocity of step 1 directly proportional to the concentration of the substrate (glucose) is a mechanism called....
    "substrate level control"
  123. Vint=?
    vint=constant x S-init
  124. constant=?
    (k-cat x E-tot)
  125. Vinit is _______ to s init
  126. glucose binds ______ tightly to muscle hexokinase than to liver glucokinase.
  127. it takes only about ___mM glucose to half-saturate the muscle iso-enzyme.
  128. it takes ___mM glucose to half-saturate the liver iso-enzyme
  129. the glucose concentration giving a velocity that is 1/2 of V-max is numerically equal to the value of ____.
  130. Muscle hexokinase , but not liver glucokinase is allosterically _______ by its own product G6P
  131. insulin initiates a series of events leading to "export" of glucose transporters to the plasma membrane on the ......
    exterior of muscle and fat cells
  132. the glucose transporter is called...
  133. GLUT 4 is stored in the ....
    membrane of small sacs called vesicles
  134. exocytosis is when..
    you move something from the inside to the cell to the outside
  135. endocytosis is when..
    you move something from the outside of the cell to the inside
  136. insulin facillitates conversion of glucose into glycogen not only by activating glycogen synthase, but also by increasing the concentration of active _________.
    glucose transporters
  137. in the cori cycle, muscle lactate goes to the ....
  138. lactate/liver equation
    lactate + NAD -> pyruvate + NADH
  139. the complete cycle of moving organic molecules from the muscle to the liver and then back to the muscles is called the....
    Cori Cycle
  140. The cost of the cori cycle is...
    4 ATPs per glucose
  141. __-__% of americans are afflicted by diabetes
  142. _______ deaths per year from diabetes in 1995
  143. ___th greatest cause of death by disease (diabetes)
  144. The cofactor permanently bound to pyruvate oxidative decarboxylase is
  145. A metabolite having the same ratio of C:H:O found in glucose is
    lactic acid
  146. Three cofactors are strongly bound to PDH. The two cofactors which diffuse thru solution, temporarily binding to PDH, are
    NAD+ and CoA
  147. The PDH cofactor which is described as being an "electron sink" is
  148. The three major molecules in the process converting pyruvate to ethanol are pyruvate CH3-C(=O)-COOH -> acetaldehyde CH3-C(=O)-H -> ethanol (CH3-CH2-OH). The enzymes which accomplish this are
    pyruvate decarboxylase and alcohol dehydrogenase
  149. Which of the following cofactors participates directly in both of the oxidation/reduction reactions occurring during fermentation of glucose to ethanol?
    NAD+ / NADH
  150. Conversion of glucose into two lactates is best characterized as no net
    oxidation or reduction..
  151. Which of the following statements about PDH is FALSE?

    The multienzyme complex is located in the mitochondrial matrix.
    Both NAD+ and a flavin nucleotide act as electron acceptors.
    The carbon of the methyl group (CH3) of pyruvate is converted into CO2.
    Two types of cofactors participating in PDH have an SH form.
    The carbon of the methyl group (CH3) of pyruvate is converted into CO2.
  152. The reason why yeast cells convert pyruvate to ethanol and CO2 under anaerobic conditions is
    to recycle NADH back to NAD+
  153. Consider the sequence of enzymes E1 -> E2 -> E3 in the pyruvate dehydrogenase complex. E3 is..
    dihydrolipoyl dehydrogenase
  154. Which of the 5 cofactors (CoA, TPP, lipoic acid, FAD, NADH) contain(s) a sulfur atom somewhere in its structure:
    CoA, TPP, and lipoic acid
  155. Vitamins are precursors for...
  156. In the PDH reaction series, the bond between the C=O and COOH groups of pyruvate is weakened by ___ the electron density in that bond. The group responsible for this effect is a ___ .
    decreasing ; N+ in TPP
  157. Two types of amino acids having a direct one-step input into the TCA cycle are
    asp and glu
  158. Feature(s) shared by the TCA cycle and beta oxidation (breakdown of FA's) include
    (1) "growing" a carbonyl group, and (2) a cyclic-like process
  159. Citric acid, which occurs at the beginning of the citric acid cycle, contains ___ carbon atoms and ___ carboxyl groups.
    6 C's ; 3 COOH
  160. Which cofactor is required for conversion of succinate to fumarate in the citric acid cycle?
  161. In terms of numbers of high energy compounds directly produced, the dominant high-energy product of the TCA cycle itself is
  162. Pathways(s) NOT located in the mitochondrion :
  163. Production of ATP or GTP is seen in
    glycolysis and the TCA cycle
  164. NADH is produced in
    glycolysis, PDH, and the TCA cycle
  165. The products of one trip thru the TCA cycle are 2 CO2's and
    3 NADH, 1 GTP, and 1 FADH2
  166. If both carbons of the entering acetyl group from acetyl-CoA are radioactively labelled, and if the TCA cycle runs only once, the number of radioactive CO2 molecules released will be
  167. The reaction used to convert alpha-ketoglutarate into succinyl-CoA resembles
    the PDH process
  168. An enzyme which catalyzes the reaction X + Y + ATP(or GTP) -> X-Y + ADP(or GDP) + Pi is called a
  169. When citrate is bound to the enzyme aconitase, the two CH2-COOH groups are
  170. The translocation reaction which moves ATP from the matrix to the intermembrane space derives its energy from
    the presence of the proton gradient
  171. Which of the following does NOT participate in electron transport that begins with transfer of electrons from succinate to FAD?
    complex I
  172. Ubiquinone (coenzyme Q = CoQ) picks up electrons (e-) from
    both complexes I and II
  173. Complex III receives e- directly from ___ and passes them on directly to ___ .
    (from) ubiquinone ; (to) cyt c
  174. Consider proteins in the electron transport chain which might be called cyochrome c reductase or cytochrome c oxidase. The protein which would appear AFTER cyt c in an electron transport chain is cytochrome c
  175. The location of the F1 portion of ATP synthase is _____ of the inner mitochondrial membrane
    on the matrix side
  176. In eukaryotes, aerobic respiration requires an intact ____ membrane.
    mitochondrial inner membrane
  177. Highly mobile electron carrier(s) in the electron transport chain include(s)
    cytochrome c and coenzyme Q
  178. A protein complex which is not involved in pumping protons out of the matrix is complex
  179. The role of gradient dissipation is to force
    the F1 complex to release newly synthesized but tightly bound ATP
  180. diabetes is the...
    inability of cells to take up glucose from blood. = high concentration of blood glucose.
  181. cost of diabetes per yr?
    $100 Billion
  182. glycosylation of proteins do not require...
    an enzyme catalyst
  183. glycosylation rxn occurs at ...
    amino groups (N-terminus and lysine sidechains)
  184. the rate of the glycosylation rxn depends on...
    the concentration of glucose in the blood
  185. the primary harmful effect of diabetes is...
    damage to blood vessels
  186. plasma leaks into..
    the lymph system
  187. lymph flows through lymph nodes to filter _____ out of the plasma.
  188. diabetes glycosylation of lysine interfere with the formation of a proper...
    collagen network
  189. macrophages bind to glucose-collagen units and release...
  190. leukotrienes stimulate neighboring cells to....
    divide and proliferate to secrete new collagen
  191. the new and extra collagen thicken and stiffen the walls of the _____, decreasing their elasticity and blood flow.
    blood vessels
  192. lipoproteins are particles used to transport...
    nonpolar lipids thru the blood
  193. lipoproteins contain ...
    nonpolar TAG's coated by amphipathic phospholipids and particular proteins plus additional cholesterol to fill in gaps and help the particle.
  194. the major serious symptoms of diabetes are...
    • heart attacks
    • amputation of limbs
    • Blindness
    • Kidney Failure
  195. early-stage symptoms of diabetes are...
    • feeling tired
    • increased urination
  196. what causes increased urination in diabetics?
    osmostic pressure effects, extra water leaves the kidneys to enter the glucose-rich urine.
  197. mid-stage symptoms of diabetes are?
    • numbness in hands and feet
    • vision problems
    • male impotence
  198. baseline of healthy glucose conc.
    80-120 units (mg/dl)
  199. healthy: max amount of glucose right after a meal does not exceded ____ units
  200. healthy: within 2 hrs after a meall, level has dropped to a value below _____.
  201. healthy individual has ___-____% glycosylation
  202. risk factors for diabetes? (6)
    • heredity
    • diet
    • sedentary lifestyle
    • age>40
    • stress
    • obesity
  203. type 1 diabetes has a ___ onset
  204. type 1 diabetes is _____-dependent
  205. when you have type 1 diab, you have no ____ in your body
  206. type 2 diabetes has a ____ onset
  207. NIDDM stands for
    Non-insulin-dependent diabetes melittus
  208. in early stages of dia. 2, you have high than normal ______ levels.
  209. the problem in early stages with dia. 2 is not lower insulin but...
    diminished response (lower sensitivity) to insulin
  210. type 2 possibilities are ... (5)
    • low secretion of insulin
    • low conc. of functional insulin receptors
    • defects in the dephosphorylation cascade
    • low total level of glucose transporters
    • defect in exocytosis cascade that release GLUT 4 to surface membrane of tissues