cell bio 2a

Card Set Information

cell bio 2a
2013-02-10 11:25:58
cell bio

cell cio
Show Answers:

  1. what are the outputs and inputs of mitochondria?
    output: ATP and CO2, input: O2, fats and carbohydrates
  2. where is the pyruvate and fatty acids generated?
  3. what does the citric acid cycle generated?
    NADH, whose electrons are stripped by the electron transport chain
  4. how does electrons move through the complexes in the electron chain transport?
    each protein has higher affinity than the next for electrons
  5. what are the three protein complexes in the mitochondria membrane?
    • NADH dehydrogenase complex, cytochrome b-c1 complex, and cytochrome oxidase complex
    • carriers: ubiquinone and cytochrome c
  6. what does into the citric acid cycle and what comes out?
    acetyl CoA goes in, FADH2 and NADH and Co2 goes out
  7. what is ATP generated in sugar used for?
    flagellar motor movement
  8. where is the proton pump located in bacteria?
    inner bacterial membrane and in the space below the peptidoglycan layer
  9. what happens under starvation conditions?
    use amino acids to fuel ATP production
  10. what should you do to cells relying on glycolysis for rapid ATP production?
    remove excess NADH from cytosol to further speed glycolysis
  11. what happens under conditions of excess?
    supply cytosol with excess citrate for synthesis of fatty acids and sterols, or supply cytosol with reducing power (as NADPH) for biosynthesis using excess mito reducing power
  12. what is the ATP used for in chloroplasts?
    use energy in light to fuel production of sugar and other molecules needed by the cells
  13. What are the outputs and inputs in chloroplasts?
    • input water to replenish electron supply and Co2
    • output o2, and carbohydrate molecules from carbon-fixation cycle
  14. describe the molecular process in the chloroplasts after light hits
    chloroplasts contains thousands of light absorbing chlorophylls, energy of one chlorophyl bumps into another unti lit hits reaction center; energy causes electron to jump to a higher energy level, initiates a series of electron transfers (neighboring electrons accepts, while another donates low energy e to a deficient chlorophyll molecule, then this low energy chlorophyl receives e from water); need happen 4 times
  15. why does the photosystem and the electron transport both in thylakoid?
    when light bumps e out of photosystem, e is transported to carrier molecules; the diffusable e brings energy to pump h+ across membrane
  16. what are the complexes in chloroplasts?
    photosystem II, cytochrome comples, photosystem I and NADP reductase, which drives NADP to NADPH to liberate oxygen from 2 molecules of water
  17. what is the interior of the endomembrane system equivalent to topographically?
    extracellular environment
  18. what is phase and constitutive endocytosis?
    happens regularly
  19. what kind of proteins does free ribosomes synthesize?
    peripheral membrane, nuclear, chloroplast and cytosolic
  20. what kind of proteins are synthesized by the rough ER?
    integral, secreted, lipids
  21. describe the structure of the ER.
    continuous with the outer nuclear membrane, anastrosomes: meshwork of 3-D interconnected membrane sheet 
  22. what components are necessary for integral membrane protein synthesis?
    • signal hypothesis (secreted and integral membrane proteins, 6-15 nonpolar a.a.s, cotranslationsl)
    • SRP-7SRNA
    • Signal peptidase
    • chaperone
    • glycosylation
  23. how is an integral membrane protein synthesized?
    • ribosomes can recognize sequence of translative protein-that's got a signal sequence. Tell ribosome to dock at specific place in ER and docking mechanism allows for translocation to middle of docking station and lumen of ER (secreted) or membrane protein to be released to membrane
    • SRP has RNA that recognizes a.a.s, halts translation, brings it to ER (receptor), and docks it to porin and translation resumes, protein snakes into lumen, signal cut with signal peptidase. Chaperone BiP drags it in and folds it
  24. when does translation continues?
    when ribosome engaged with translocon
  25. when does translation stop?
    signal recognition particle binds signal sequence on protein
  26. what does Bip help?
    folding and prevents backsliding