Ch. 8 Metabolic Metabolism

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Ch. 8 Metabolic Metabolism
2011-10-27 15:15:42

Study Guide For TEST 3 SSC, Schreiber
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  1. What is METABOLISM?
    total chemical reactions occurring in an organism, OR CELL. These reactions can include ANABOLISM or CATABOLISM
    Also referred to as Biosynthesis,it is any process that results in the synthesis of macromolecules and cell structures from precursors, simpler products. Building and bond making process that forms larger molecules from smaller ones, it usually requires an input of energy
    This process is the opposite of Anabolism, in that the reactions are degradative. It is the breakdown of complex organic molecules in order to extract energy and form simpler end products. This process releases energy
  4. What is the difference between a REACTANT and PRODUCT in a chemical reaction?
    In a chemical reaction, the REACTANT is what begins the process, and the PRODUCT is the end result.
  5. Are SUBSTRATES reactants or products?
    A Substrate is classified as the Reactant
  6. Enzyme Characteristics
    *Most are composed of protein: may require cofactors* Act as organic catalysts to speed up the rate of cellular reactions*Lower the activation energy required for a chemical reaction to proceed* Have unique characteristics such as shape, specificity, and function*Enable metabolic reactions to proceed at a speed compatible for life* Have an active site for target molecules called substrates*Are much larger in size than their substrates* Associated closely with substrates, but do not become integrated into the reaction products* Are not used up or permanently changed by a reaction* Can be recycled, thus function in extremely low concentrations* Are greatly affected in function by change of pH and temperature*Can be regulated by feedback and genetic mechanisms
  7. How do Enzymes work in a cell?
    They speed up chemical reactions in a cell
  8. Simple Enzyme
    A simple enzyme has no cofactor, it is protein alone.
  9. Conjugated Enzyme(Holoenzyme or Apoenzyme)
    This has a cofactor, meaning it is made of a protein(enzyme) and non-protein(cofactor)
  10. Interactions Between Enzymes and Substrates: "Lock and Key"
    In this way, the enzyme and the substrate are a perfect fit, meaning neither the enzyme or substrate has to bend or adjust to fit
  11. Interactions Between Enzymes and Substrates: "Induced Fit"
    In this instance, the active site must adjust and open slightly to allow the substrate to bind and complete the reaction
  12. Cofactors
    nonprotein molecules that assist enzymes, Any nonprotein molecule or ion that is required for the proper functioning of an enzyme. Cofactors can be permanently bound to the active site or may bind loosely with the substrate during catalysis
  13. Metallic Cofactors
    These include iron, copper, magnesium, and nickel
  14. Cofactors, Coenzymes
    These are organic compounds, meaning they must have carbon AND hydrogen. Some examples would be vitamins
  15. Hyrdolase
    class of enzymes that involves Hydrolysis. EX. Lipases, proteases, nucleases, amylases.
  16. Transferase
    enzyme that catalyzes the transfer of a functional group
  17. Oxioreductase
    catalyzes oxidation-reduction reactions
  18. Exoenzyme
    These are inactive while inside the cell, but upon release the become active. The enzyme and substrate come together outside of the cell
  19. Endoenzyme
    These remain in the cell and are active. The enzyme and substrate come together inside of the cell
  20. Constitutive Enzyme
    enzymes that are always present and in relatively constant amounts, regardless of the amount of substrates.
  21. Induced Enzyme
    not constantly present; production is turned on (induced) or turned off (repressed) in response to changes in concentration of the substrate. Induced turns on when there are high amounts of substrate
  22. Repressed Enzyme
    This is the opposite of an Induced Enzyme, in that it turns on when there are low amounts of substrate
  23. How are Enzymes involved in Condensation reactions
    Condensation or Dehydration reactions are associated with Anabolic reactions, the making of bonds with the input of energ
  24. How Are Enzymes involved in Hydrolysis reactions
    In Hydrolysis reactions, enzymes are breaking down bonds in order to use energy, this is an example of Catabolism
  25. Oxidation and Reduction
    O.I.L R.I.G= Oxidation Is Losing, Reduction Is Gaining, These are chemical processes that always occur together. Both involve a transfer of electrons (from one substance to another). Oxidation is the loss of electrons from a substance; reduction is the gain of electrons (LEO the lion goes GER).
  26. How is a multienzyme system used in metabolism?
    Through different types of enzyme reactions. These reactions are Dehydration, Hydrolysis, Oxidation/Reduction, and Transfer
  27. Competitive Inhibition
    The process of a substance reducing the activity of an enzyme by entering the active site in place of the substrate whose structure it mimics. It is an example of enzyme regulation in their actions. Both the substrate and the inhibitor are competing for the active site. Sulfa drugs use this process.
  28. Noncompetitive Inhibition
    the act of binding to another part of an enzyme, causing the enzyme to change shape and making the active site less effective.
  29. What is enzyme repression, also known as feedback inhibition?
    This is when end products can stop the expression of genes that encode proteins(enzymes) which are responsible for metabolic reactions
  30. Exergonic Reaction
    This is a coupled reaction that releases energy as it goes forward
  31. Endergonic Reaction
    This is a coupled reaction that is driven forward with the addition of energy
  32. Structure of ATP
    adenine, 5-carbon sugar (ribose), 3 phosphate groups. the bonds in between the phosphates are the high-energy bonds.
  33. Structure of ADP
    - Adenine (base), formed by N and NH₂- Ribose (sugar), formed by OH, O, and CH₂- 2 phosphate groups, formed by Phosphate and Oxygen
  34. Structure of AMP
    ATP is converted into cAMP by the action of the plasma membrane enzyme adenylyl cyclase. cAMP is inactivated by the systolic enzyme cAMP phosphodiesterase which converts cAMP into the noncyclized form AMP
  35. How does a cell make and use ATP?
    The making of ATP is through exergonic reactions. The breaking of ATP is through endergonic reactions. ATP can be used to phophorylate (using ATP) (catabolic reaction) an organic molecule, such as glucose. ATP can be formed through Substrate Level Phophorylation,(making ATP) an anabolic reaction used to make ATP when an enzyme is involved.
  36. Name the pathway(s) of glucose metabolism that involves glycolysis.
    Aerobic Respiration: Anaerobic Respiration: Fermentation
  37. Name the pathway(s) of glucose metabolism that involves Krebs (TCA) Cycle
    Aerobic and Anaerobic Pathways
  38. Name the pathway(s) of glucose metabolism that involves Electron Transport Chain
    Anaerobic and Aerobic Pathways
  39. Name the pathway(s) of glucose metabolism that produces acidic and alcoholic end products. What is regenerated in this pathway?
    The chemistry of fermentation systems that produce acid and alcohol.In both cases, the final electron acceptor is an organic compound. In yeasts, pyruvic acid is decarboxylated to acetaldehyde, and the NADH given off in the glycolytic pathway reduces acetaldehyde to ethyl alcohol. In homolactic fermentative bacteria, pyruvic acid is reduced by NADH to lactic acid. Both systems regenerate NAD to feed back into glycolysis or other cycles.
  40. Location of Glycolysis in Prokaryotic Cells
    In the cytoplasm
  41. Location of Glycolysis in Euakryotes
    In the cytoplasm
  42. Location of TCA, or The Krebs Cycle in Prokaryotes
    In the cytoplasm
  43. Location of TCA, or The Krebs Cycle in Eukaryotes
    The Mitochondria
  44. Location of the Electron Transport Chain in Prokaroytes
    In the cell memebrane
  45. Location of the Electron Transport Chain in Eukaryotes
    In the mitochondria
  46. The Important Steps In Glycolysis
    Step 1: ATP is phophorized into ADP+P. Step 3: Another ATP is phosphorylized into ADP+P Step 4: 6 carbon lyses into 3 carbonStep 5: NAD-->NADH, it has become reduced and 2 are sent to the E.T.C Step 6: Substrate-level-phosphorylation the making of ATP Step 8: 2 water molecules are released Step 9: Sunstarte level phosphorylation making ATPIn the end, we have 2 pyruvic acid and 4 ATP, making a net gain of 2 ATP, plus the regain of the 2 ATP that were invested. In step 5 we see a REDOX reaction, in steps 1 and 3 we see phosphorylation, and in step 6 we see substrate level phosphorylation.
  47. Electron Transport Chain: <PROKARYOTIC>
    *For every NADH that enters the ET, 3 ATP wil be made* For every FADH2 that enters the ETC, 2 ATP are made*
  48. Electron Transport Chain:<EUKARYOTES>
    *For every NADH that enters the ET, 3 ATP wil be made* For every FADH2 that enters the ETC, 2 ATP are made*
  49. How is gluconeogenesis different from glucose metabolism?
    Gluconeogenesis is the generation of glucose from pyruvate (intermediate) is converted to glucose, and occurs when the glucose supply is low. Glycolysis is backwards, begining with the pyruvic acid.
  50. Light Dependent Reactions
    Loccated in the chloroplast in the thylakoid membrane. Sunlight is used to harvest energy from water which becomes oxidized turning into oxygen. ADP is added with another P to become ATP, this is not a form of substrate level phosphorylation. NADP is reduced to NADPH, making NADP an electron carrier, Both the independent and dependent reactions make glucose, which is stored as startch.
  51. Light Independent Reactions
    Also known as The Calvin Cylcle, this is located in the chlorplast, in the stroma. ATP is broken into ADP+P, NADPH is oxidized into NADP. The first step in these reactions is the use of CO2. Both the independent and dependent reactions make glucose, which is stored as startch.