Cellular metabolism Micro

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Cellular metabolism Micro
2015-10-28 22:49:47
Endosymbiosis metabolism catabolism
Microbiology lecture exam 2
Study Guide: info from textbook
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  1. After glucose is catabolized, it is oxidized. How do the electrons get transported from glucose? (Hint: ETC)
    Many of the electrons are released from glucose and accepted by NAD+, reducing it to NADH. Electrons are then transferred to O2, using the electron transport chain.
  2. Where are Bacterial electron transport chains located within the cell?
    Some bacteria have ETC carriers in the periplasmic space and even the outer membrane.
  3. 1. This term is used to describe a mutually beneficial relationship between two organisms.
    2. What is a microbe that interacts with a larger organism
    • 1. Symbiosis
    • 2. Symbiont
  4. What was the product of the endosymbiosis theory and how was it supposedly done?
    • Today's Mitochondria: It was thought that Prokaryotes inhabited larger prokaryotes (definition of symbiosis)
    • Instead of the larger organism consuming the smaller one, they formed a "lasting relationship"
    • This is the idea of how the inner and outer membranes of mitochondria was formed.
  5. This term means a succession of chemical reactions that constructs or synthesizes molecules from smaller components, usually requiring energy in the process.
  6. T or F: Enzymes are used for both catabolic and anabolic processes
  7. Is anabolism exergonic or endergonic? How is it done?
    • Endergonic: many reactions in anabolism consumes energy.
    • It is done by connecting the energonic reactions to the breakdown of ATP, which drives the reaction.
  8. Is the process of oxidizing electrons (removing electrons) and storing them in other accessible high energy bonds like ATP, anabolic or catabolic?
    Catabolic: catabolism provides energy for our cells
  9. What is the definition for anabolism? catabolism?
    • Anabolism is the building up of things - a succession of chemical reactions that constructs or synthesizes molecules from smaller components, usually requiring energy in the process.
    • Catabolism is the breaking down of things - a series of degradative chemical reactions that break down complex molecules into smaller units, and in most cases releasing energy in the process.
  10. What is an Amphibolic Pathway?
    • When a metabolic pathway has enzymes that function both catabolically and anabolically.
    • An example of this is there will be a catabolic function during glycolysis, but anabolic during gluconeogenesis, when glucose is generated from pyruvate and other small molecules
  11. This is the most common metabolicc pathway and is used to oxidize glucose to two molecules of pyruvate.
  12. How many ATP molecules go in and out of glycolysis?
    • 2 ATP are used to transfer energy to the pathway (2ATP ->2ADP)
    • 4 are made as energy becomes vailable from the oxidation of the carbon molecules of the split glucose. (4 ADP -> 4 ATP
  13. During glycolysis, how do electrons get transfered from glucose molecules?
    • The electrons from glucose are transferred to 2 NAD molecules, which get reduced to 2 NADH.
  14. What are the substrates and end products of glycolysis?
    • Substrates: Glucose is the substrate. Inserted into the metabolic pathway are also 2 ATP and 2 NAD for each of the split up carbon chains of glucose.
    • End products: 2 pyruvic acid, 4 ATP (2 net ATP), 2 NADH
  15. What are the substrates and end products of the entner-duodoroff pathway?
    • Substrate: glucose, ATP (to ADP), NADP (to NADPH)
    • Intermediates: Glucose is eventually formed to KDPG
    • End products: 1 pyruvate and 1 glyceraldehyde 3-phosphate
  16. In the first part of the entner-duodoroff pathway, what are the end products? What are the end products of the 2nd part?
    • 1st part: 1 pyruvate + Glyceraldehyde 3-phosphate
    • 2nd part: Glyceraldehyde 3-phosphate is catabolized to a 2nd pyruvate + 2 ATP +1 NADH
  17. T or F: The entner-duodoroff pathway has a net yield of 2 ATP
    False: One ATP is used in the first part
  18. This enzyme in DNA replication seperates the DNA strands. How does it do this?
    Helicase: disrupts the hydrogen bonds that hold the two strands together
  19. This enzyme in DNA replication provides a starting place for DNA polymerase III. How does it do this?
    Primase (RNA polymerase): It synthesizes short strands of RNA (primers) that are complementary to the DNA
  20. This enzyme in DNA replication synthesizes the new strands of DNA complementary to the original. It works directly with Primase.
    DNA polymerase III: Using a template from original strand, it adds nucleotides to the 3' en of the growing strand.
  21. T or F: DNA polymerase can begina  strand by itself.
    False: It is primed by Primase (RNA polymerase), meaning it is provided with a starting place.
  22. This enzyme in DNA replication cleans out RNA out of the new DNA. How does it do this?
    DNA polymerase I: It removes the RNA primers and replaces them with new DNA
  23. This enzyme in DNA replication seals the breaks in the backbone of the new DNA strand. How does it do this?
    DNA ligase: It catalyzes the formation of covalent bonds along with the sugar phosphate backbone between the fragments.
  24. Explain lactic acid fermentation.
    • After glycolysis (2 pyru, 2 ATP, and 2 NADH). The NADH transfers its electrons back to pyruvate.
    • Pyruvate is acting as the electron acceptor, and is reduced to lactic acid.
    • NAD is regenerated and glycolysis can occur again.
  25. When does ethanol fermentation occur and what occurs?
    • Occurs after glycolysis: carbon is removed from pyruvate as CO2, meaning it is decarboxylated (carbon is removed)
    • It becomes acetaldehyde
    • Acetaldehyde serves as the electron acceptor and becomes ethanol
  26. Anabolism is ____, and catabolism is _____. (Endergonic/exergonic)
    • Anabolism is endergonic
    • Catabolism is exergonic
  27. What is the overall reaction for the pentose phosphate pathway?
    Glucose 6-phosphate + 2 NADP+ + H2O → ribulose 5-phosphate + 2 NADPH + 2 H+ + CO2
  28. What is the chemical reaction of turning pyruvate to Acetyl-CoA?
    • Pyruvate (a 3 carbon chain) is decarboxylated (loses a carbon in the form of CO2).
    • The two remaning carbons are attached to coenzyme A.
    • NAD is reduced to NADH.
  29. What is substrates and end products of kreb's cycle?
    • Substrate: Pyruvate turns into acetyl CoA
    • End Products: 
    • 6 CO2
    • 8 NADH
    • 8 H+
    • 2 FADH
    • 2 ATP
    • h2o
  30. Glycolysis substrates and end products?
    • Sub: 
    • Glucose
    • 2 ATP
    • 2 ND
    • EP:
    • 2 pyruvate
    • 2 NADH
    • 2 ATP
  31. Ethanol fermentation sub and end products?
    • Sub: 
    • 2 pyruvate
    • 2 NADH
    • EP:
    • Pyru -> acetlldehyde -> 2 ethanol
    • 2 NAD
  32. Lactic acid fermentation sub and end products?
    • Sub:
    • 2 pyruvate
    • 2 NADH
    • EP:
    • 2 lactic acid
    • 2 NAD
  33. ETC sub and end products?
    • Sub:
    • NADH
    • FADH
    • EP:
    • ATP
    • NAD + FAD
    • H2O
  34. This metabolic pathway changes glucose to pyruvate, produces no ATP, but receives carbon backbone for cells.
    Pentose phosphate pathway
  35. What is glucose also known as?
    Embden-Meyerhof Pthway: the six-carbon backbone of lucose is split into two 3-carbon molecules
  36. The ATP made during glycolysis is made by a process called ____.
    Substrate-level phosphorylation: addition of a phosphate (ADP -> ATP)
  37. What are the two substrates of pentose phosphate pathway?
    • 1. Ribose-5-phosphte
    • 2. NADPH
  38. What is the primary role of NADPH synthesized in the pentose phosphate pathway?
    • Primary role is donting electrons, which is important for anabolic reactions (reducing power)
    • Also important for maintaining anti-oxidants
  39. Wht is an alterntive to the embden-meyerhof pathway(EMP)? What are its substrates and end products?
    • Some prokaryotes will go through the Entner-Duodoroff Pathway (EDP). 
    • Initially in EMP, the end products will have 2 pyruvates.
    • In EDP, it will hve 1 pyruvate and  glyceraldehyde 3-phosphate.
    • The G3P will further catabolized to another pyruvate + 2 ATP + NAD -> NADH
    • So the equation will be
    • Glucose + ATP -> 1 pyruvate + Glyceraldehyde 3-phosphate -> Original Pyruvate + Another pyruvate + 1 Net ATP + NADH
  40. What is the substrate and end products of the pentose phosphate pathway?
    Glucose 6-phosphate + NADP + H2O -> CO2 + NADPH + H ions + Pi
  41. This protein in the ETC membrane allows potential energy from the proton motive force to be transferred to ATP.
    It allows the H+ to diffuse back across the membrane, catalyzing the formation of ADP and P ->ATP.
    ATP Synthase