Anatomy Exam 1 Part 2

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Anatomy Exam 1 Part 2
2010-09-28 12:42:22
anatomy wahida

exam 1 review
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  1. describe passive process
    substances moving down concentration/electrical gradient; no energy req'd
  2. describe active process
    against chemical/electrical gradient or unable to pass bc of permeability factors; reqs energy (ATP0
  3. what are the 3 passive processes?
    diffusion, facilitated diffusion, osmosis
  4. what r the 2 types of active processes?
    active transport and vesicular transport
  5. what is secondary active transport?
    energy from concentration gradient helps 2move substances across; doesn't req ATP
  6. what is primary active transport?
    uses energy to move substance against its concentration/electrical gradient. reqs carrier proteins. uses enzymes (ATPase) to break high energy phosphate bonds of ATP
  7. what is vesicular transport?
    way for larger molecules to get in and out of cell; reqs ATP
  8. what is endocytosis? and what r the 3 types?
    • moving substances into cell via vesicles.
    • 3 types: pinocytosis, phagocytosis, and receptor-mediated endocytosis
  9. what is pinocytosis?
    a form of endocytosis; "cell drinking", brings inextracellular liquids and dissolved substances
  10. what is phagocytosis?
    a form of endocytosis; "cell eating"; brings in large particles by forming pseudopodia (evaginations surround larger particles to form phagocytic vesicles)
  11. what is receptor-mediated endocytosis?
    avery selective in what it IMPORTS. membrane contains binding sites for specific substances = protein receptors
  12. what are the two types of vesicular transport?
    endocytosis and exocytosis
  13. what is exocytosis?
    moving substances out of cell. substance is enclosed in vesicle which moves to plasma membrane and dumps contents to outside of cell
  14. what r some examples of exocytosis?
    hormone secretion, neurotransmitter release, mucus secretion
  15. what r microvilli?
    finger-like projections of plasma membrane
  16. what is cilia?
    propels substances along surface of cell. found in respiratory tract
  17. what is flagellum?
    propels entire cell. only cells in body w/flagella r SPERM
  18. what r the 3 types of membrane junctions btwn cells?
    tight junctions, desmosomes, and gap junctions
  19. what is a tight junction?
    keeps cells close together so nothing can pass in btwn. proteins fuse to keep substance from passing. Ex btwn cells lining digestive tract.
  20. what is a desmosome?
    adjacent cells r held together by linking proteins to keep cells from coming apart. found on cells with pull/tension/force. Ex. heart muscle, skin
  21. what is a gap junction?
    cells connected by cylindrical proteins. allows comm btwn cells. Ex. heart muscle 9allows flow of ions btwn cells)
  22. describe the cytoplasm.
    material btwn plasma and nuclear membrane. contains cytosol (intracellular fluid) and organelles
  23. what r the organelles of the cytoplasm?
    cytoskeleton, ribosomes, ER, Golgi apparatus, lysosomes, mitochondria
  24. what is the cytoskeleton?
    network of proteins that provide strength & structural support. composed of filaments
  25. what r the 3 types of filaments the cytoskeleton is made up of?
    microfilaments aka actin filaments, intermediate filaments, and microtubules
  26. what r ribosome?
    • responsible for protein synthesis
    • 2 types: free and fixed
  27. what is the ER?
    endoplasmic reticulum - a netwk of intracellular membranes. a site for synthesis of proteins, lipids, and carbs.
  28. diff btwn smooth and rough ER?
    • smooth - no ribosomes; lipid and carb synthesis
    • rough - fixed ribosomes on outer surface; protein synthesis
  29. what is purpose of Golgi Apparatus?
    packages & modifies molecules from ER for secretion (exocytosis), incorporation into the plasma membrane, or use w/i the cell (lysosome)
  30. describe lysosomes
    • vesicles containing digestive enzymes
    • perform cleanup and recycling function - fuse w/damaged organelles or endocytic vesicles to digest contents and release nutrients
  31. what is the mitochondria?
    responsible for energy (ATP) production. process of energy production = aerobic respiration
  32. describe the nuclear envelope
    double membrane layer. surrounds nucleus. has nuclear pores
  33. what is the purpose of nuclear pores?
    allows communication btwn nucleus and cytoplasm
  34. what is chromatin?
    the uncondensed form of a chromosome, which holds DNA
  35. what is a chromosome?
    the condensed form of a chromatin
  36. what happens in nucleoli?
    ribosome assembly. mature ribosomes move to cytoplasm thru nuclear pores
  37. what is the purpose of cell division?
    req'd for growth of organism and replacement of worn-out cells
  38. what are the two major steps of cell division?
    interphase and mitosis
  39. Interphase is composed of what smaller phase?
    G1, G0, S, and G2
  40. describe G1 phase
    period of cell growth
  41. describe G0 phase
    non-dividing phase. cells may exit cell cycle.
  42. describe S phase
    DNA replication (double helix uncoils, each strand serves as template 4synthesis of complementary strand, each new double helix has 1 old &1 new strand)
  43. describe G2 phase
    growth and final preparation for mitosis and cell division
  44. what is mitosis?
    chromatin condenses into chromosomes; duplicated DNA molecules condense into pair of sister chromatids; nuclear membrane breaks down; spindle fibers form
  45. describe metaphse
    chromosomes align at equator
  46. describe anaphase
    sister chromatids separate and move to opposite poles
  47. describe telophase
    "reversal" of prophase (spindle disappears, nuclear envelope reforms, chromosomes decondense into chromatin)
  48. describe cytokinesis
    cytoplasmic division by contractile ring @ cleavage furrow
  49. what r the 2 phases of gene expression and protein synthesis
    transcription and translation
  50. what is gene expression and protein synthesis?
    process where info in DNA (genes) is use to direct protein synthesis
  51. what is transcription?
    DNA -> mRNA; occurs in nucleus. one strand of DNA (template strand) is used to guide synthesis of mRNA
  52. pre-mRNA is synthesiszed by which enzyme?
    RNA polymerase
  53. what is RNA processing?
    pre-mRNA is processed to form a mature mRNA
  54. where is mRNA exported from/to in transcription?
    from nucleus to cytoplasm
  55. describe translation
    mRNA -> protein; occurs @ribosome (in cytoplasm). 3 stages
  56. what is a codon?
    3 bases in mRNA which specify an amino acid => genetic code
  57. what r the 3 stages of translation?
    initiation, elongation, and termination
  58. describe stage 1 of translation
    initiaion: ribosome assembles on mRNA. tRNA carrying 1st aa binds mRNA/ribsome complex @P-site. binding occurs btwn the codon in the mRNA & the anticodon in the tRNA
  59. what r the 3 sites of the ribsome?
    E, P, and A
  60. describe 1st part of stage 2 of translation
    elongation: tRNA carrying next aa arrives @adjacent binding site in ribosome (A site)aa's @ P & A sites joined by peptide bond thru dehydration synthesis.
  61. describe 2nd part of stage 2 of translation
    tRNA in P site releases its aa. ribosome moves down mRNA by 3 bases (tRNA in Psite moves into Esite, & then exits ribosome; new codon occupies Asite & is ready 2get next tRNA). steps rpt til stop codon in mRNA
  62. summary of mvmt of tRNAs during stage 2 of translation
    elongation: cytoplasm -> Asite -> Psite -> Esite -> cytoplasm
  63. describe third/final stage of translation?
    termination; protein released from last tRNA; ribsome dissociates from mRNA