cell bio exam II set II

Card Set Information

cell bio exam II set II
2014-03-18 01:03:32
cell biology
cell biology
2nd set of cards for exam 2
Show Answers:

  1. basic structure of the contractile muscle, myosin & actin filaments
  2. proteins that bind to + end of actin filaments to stop branching
  3. what are fluid and macromolecules take up by?
  4. the vesicles that are used in the process of pinocytosis
    pinocytic vesicles
  5. 4 things the actin filaments are for?
    • microvilli
    • small contractile bundles
    • dynamic protrusions
    • contractile ring(cytokinesis)
  6. * dense-rich in protein
    * ribosome factory
    * really active area
  7. * detox
    * enzymes to break down toxins
    * eggs & sperms for cleavage
    * Ca storage
    * lipid synthesis
    Smooth ER
  8. place that attaches signals to proteins
    Golgi Apparatus
  9. pore that requires a charge to get through
    protonatious pore
  10. cell crawling, finger like sensing, straight bundles
  11. How is actin filaments polymerized?
    ATP and hydrolysis
  12. if hydrolyzing for microtubules is faster then polymerization
    dynamic protrusions
  13. nucleating site for microtubulars to start polymerization
    gama tubulin ring complexes
  14. Region where Microtubules grow
    GTP cap
  15. types of transporters epithial cell has
    uniporter, symporter, and antiporter
  16. Clathrin coated endocytosis process
    • cargo protein binds to receptor on membran
    • receptor clusters, vesicle forms
    • adaptin binds to receptor
    • calthrin binds to adaptin-makes shell
    • dynamin wraps around and pinches off
    • free vesicle
    • clathrin disassociates
    • vesicle->endosome
  17. Import of Proteins to ER
    • mRNA translating in cytosol
    • 1st sequence is signaler
    • Signal-recognition particle binds and stops coding
    • whole complex moved to SRP receptor of ER
    • SRP displaced and removed
    • sequence and ribosome moved to translocator
    • synthesis continues
    • protein is embedded in ER membrane
    • peptidase cleaves and stops
  18. Nuclear import procedure:
    • cargo protein in cytosol gets nuclear localization signal(NLS)
    • binds to nuclear transport receptor
    • forms complex, moves into nucleus
    • Ran-GTP bind to nuclear transporter, releases cargo protein
    • ran-gtp & transporter return to cytosol
  19. gated channel in the muscle
    ligand gated Na+
  20. gated channel in the neuron
    Ca2+ voltage gated channel
  21. What happens at the presynaptic membrane:
    positive charge in the membrane from action potential increase causes acetyl CoA vesicle to release its concentration into the synaptic cleft
  22. What happens at the postsynaptic membrane
    acetyl CoA binds to channels on membrane, channels open, positive charges increase causing contraction/transfer of information
  23. proteins that flip a phospholipid from outer membrane to inner
  24. proteins that flip a phospholipid from inner to outer
  25. Allows movement of solute high to low, simple, gated
    channel protein
  26. switches, specific chemical to bind to substrate, will flip over releasing substrate
    carrier proteins
  27. active transport, uses ATP, against electro and chemical gradient
    Ion Channel
  28. ion channels that do not use ATP, uses another molecule for energy,
    co transporters, symporter and antiporter
  29. Action potential rxn:
    • gated ion channels closed
    • cell is stimulated w/ neurotransmitters
    • Na volted gated channel open, creates positive charge in cell
    • membrane depolarizes, increases permeability to Na+
    • at peak Na+ channels close & lock
    • K+ voltage gated ion channels open
    • cell increases permeability to K+
    • repolarization, hyperpolarization
    • Na+ ion channels unlock, ready
  30. Type of exocytosis that does not require a signal to transfer molecules
    vesicles buds from trans Golgi and fuses w/plasma membrane
    Constitutive exocytosis pathway
  31. how does regulated exocytosis pathway work?
    • * specialized cells have secretory cell
    • * large amount of special product(hormone) stored in secretory vesicles
    • * bud off from trans Golgi, accumulate near plasma membrane
    • * wait for signal, fuse to membrane, release
  32. phagocytosis process
    • endocytosis:
    • * particles bind & activate receptor
    • * receptor recognizes antibody
    • * phagocytic cell extends pseudopods(sheetlike projections of plasma membrane)
    • * engulf & fuse tips
    • * fuse with lysosome, microbe destroyed
  33. how does pinocytosis work?
    also called vesicle budding
    • * receptors outside of cell
    • * cargo molecules bind
    • * adaptin, clathrin coated vesicle
    • * forms vesicle, pinched with dynamin
    • * delivered to endosome
  34. how does a newly budded vesicle inside the cell get the materials to where they need to be?
    • * transported by microtubule motor proteins
    • * GTPases/Rab proteins recognized by tethering proteins on target membrane
    • * vesicle snare interlaces with target snare
    • * bilayers pulled close and fused to release contents
  35. Explain Receptor-Mediated endocytosis
    • 1. Macromolecules bind to extracellular membrane receptors
    • 2. clathrin coated vesicle forms
    • 3. coated
    • 4. delivered to endosome
    • 5. materials delivered to lysosome, hydrolyzed
  36. Lysosome membrane
    • * transporters for digested final products to cytosol
    • * ATP-driven H+ pump, H+ into lysosome
    • * proteins facing lumen highly glycosylated to protect from digestion by the proteases
  37. When cell eats itself
    • autophagy,
    • autophagosome
  38. what chemicals can pass through the membrane?
    • steroid homrones
    • thyroid hormones
    • Nitric oxide NO
    • O2
    • CO2
  39. type of proteins pump that is used at resting potential to pump 3 Na+ out and 2 K+ in
  40. a long, thin, flexible rod that forms a meshwork that provides support for the plasma membrane and maintains cell shape
    dimeric protein spectrin
  41. shifts small organic molecules or inorganic ions from one side of membrane to the other by changing shape
  42. form tiny hydrophilic pores across the membrane through which such substances can pass by diffusions
  43. pore that only permit passage of inorganic ions
    ion channels
  44. what type of transporters does mitochondrial have?
    ATP and pyruvate transporters
  45. what type of transporters does the plasma membrane have?
    • sugars
    • amino acids
    • nucleotides
  46. explain the Na+ pump
    • * ATP gets Na+ out against electrochemical gradient
    • * Na+ flows back in through Na+ coupled pumps
    • *
  47. the symport, antiport and uniport are what?
  48. what transporters and in what order (gut lumen ->extracellular fluid) are they?
    • Na+-driven glucose symport
    • Passive glucose uniport/Na+ K+ ATPase pump
  49. what gated channel is controlled by membrane potential
    voltage-gated channel
  50. what gated channel is controlled by the binding of some molecule?
    ligand-gated channel
  51. explain how mechanically-gated channels work
    • 1. some force moves the channel
    • 2. causes ions to flow into cell
    • 3. electrical signal transmitted to the brain
  52. what channels are on the pre-synaptic nerve terminal and what do they do?
    • 1. voltage-gated Ca2+,
    • 2. Ca2+ rushes into nerve terminal
    • 3. triggers membrane fusion of vesicles that release neurotransmitters