Bio 12-14

  1. zygote
    fertilized egg
  2. Functions of Cell Cycle
    • Heals wounds
    • Replaces damaged cells
    • Growth
    • Reproduction (only on that incudes meiosis)
  3. Genome
    all DNA in a cell
  4. Chromosome
    • One molecule of DNA is wrapped around proteins to form a chromosome
    • contains hundreds of genes
  5. Gene
    section of DNA that has the instructions for making one protein
  6. Before cell division...
    • DNA needs to be doubled
    • Each newly made daughter cel must receive the exact amount of genetic material as the parent cell
  7. Loci
    Location of a gene
  8. DNA Replication
    • Results in two identical DNA molecules
    • Exactly the same b/c of base pairing rule
  9. centromere
    where sister chromatids are attached
  10. Phases of the cell cycle
    • Interphase (cell growth and copying of chromosomes in preparation for cell division)
    • Mitosis
    • Cytokinesis (division of cytoplasm)
  12. Cell spends majority of life in
  13. 3 phases of interphase
    • G1 = Gap 1
    • G2 = Gap 2
    • S = DNA Synthesis
  14. How do proteins trigger events in the cell cycle?
    • The cyclin-dependent kinase (Cdk) transfers phosphates and only works when cyclin is present.
    • Control whether cells get through checkpoints or not
    • Cell makes cyclin when ready to move on
    • protein + ATP --> protein-P +ADP
  15. Mitosis
    • Division of nucleus
    • Followed by cytokinesis (cytoplasm division)
    • Purpose: separate sister chromatids so each new cell has complete set of chromosomes - exact genetic match to original cell
  16. Phases of Mitosis
    • Prophase
    • Prometaphase
    • Metaphase
    • Anaphase
    • Telophase
  17. Chromatin
    long stringy form of DNA strands - condesnse to chromosomes, which condense further
  18. Prophase/Prometaphase
    • Chromosomes condense
    • Nuclear membrane dissolves
    • Mitotic spindle forms
  19. Mitotic Spindle
    Microtubules attach to kinetochores (proteins) at one side of the centromere
  20. Metaphase
    • Chromosomes align along lateral plane
    • Microtubules shorten and eventually centromere can't hold any more
  21. Anaphase
    Separate sister chromatids (separate exact DNA copies)
  22. Telophase
    • Chromosomes migrate to poles
    • Prepares for cytokinesis
    • Nuclear membrane reforms
  23. Cleavage Furrow
    Cytoplasm divides in clevage furrow (outside-in) in animals
  24. Cancer
    Unregulated cell division
  25. Tumor
    • Mass of cells with no function
    • can be benign or malignant
  26. Benign tumor
    doesn't afect surrounding tissues
  27. Malignant tumor
    invades surrounding tissues; cancerous
  28. Metastasis
    cells break away from a malignant tumor and start a new cancer at another location
  29. Cancer cells vs. Normal cells
    • Cancer cells:
    • Divide when they should not
    • Invade surrounding tissues
    • Move to other locations in the body
  30. Mutation
    Change in the info that a gene carries or a change in the sequence of nucleotides of a DNA molecule
  31. Carcinogens
    • substances that damage DNA and chromosomes
    • Ex: cigarette soke, UV light
  32. Proto-oncogenes
    • Before cancer genes
    • says go or not go (conditions must be right)
  33. Oncogene
    • cancer gene
    • says go, go, go, no matter what
  34. Tumor suppressor
    stops tumors from forming if there is an oncogene
  35. Mutated tumor suppressor
    One must have an oncogene AND a mutated tuor suppressor in order to get cancer
  36. Tumor Characteristics
    • Angiogenesis (vessel formation)
    • Immortality (don'r dies as long as the have the oxygen and nutrients needed)
    • Lack of contact inhibition (when they come in contact with each other, they don't stop dividint like skin cells, rather pile up)
    • Lack of anchorage dependence (allows for metasticization)
  37. Genetics
    scientific study of heredity and variation
  38. Heredity
    transmission of traits from one generation to the next
  39. Genes
    units of heredity; made up of segments of DNA
  40. Gametes
    • reproductive cells
    • have one set of chromosomes (23 total)
    • produced by meiosis
  41. Somatic cells
    • nonreproductive cells
    • have 2 sets of chromosomes (46 total)
    • produced by mitosis
  42. Autosomes
    22 pairs of chromosomes that do not determine the sex
  43. Karyotype
    sum of all homologous chromosomes in a cell
  44. Homologous chromosomes
    2 chromosomes in each pair
  45. Diploid cell
    • 2n
    • 2 sets of chromosomes
    • Humans diploid number is 46 (2n=46)
  46. Haploid
    • n
    • containsa single set of chromosomes
    • Human haploid number is 23 (n=23)
  47. Meiosis
    • reduces the numver of chromosome sets from diploid to haploid
    • Preceded by replication of chromosomes
    • Two sets of cell division (Meiosis I an meiosis II)
    • Results in 4 daughter cells
  48. Stages of Meiosis
    Meiosis I and Meiosis II
  49. Meiosis I
    • Homologous chromosomes separate
    • Reductional division
  50. Mieosis II
    • Sister chromatids separate
    • Equational division
  51. Synapsis
    Homologous chromosomes pair by adhering along their lengths
  52. Meiosis I: Prophase I
    Chromosomes begin to condense
  53. Meiosis I: Metaphase I
    • Tetrds line up at metaphase plate
    • Microtubules attach
  54. Meiosis I: Anaphase I
    Homologous chromosomes separate
  55. Meiosis I: Telophase I
    • Each half of cell has haploid set of chromosomes
    • Each chromosome still consists of 2 sister chromatids
  56. Meiosis II: Prophase II:
    spindle apparatus forms
  57. Meiosis II: Metaphase II
    Sister chromatids line up at metaphase plate
  58. Meiosis II: Anaphase II
    Sister chromatids separate and move as individual chromosomes toward opposite poles
  59. Meiosis II: Telophase II
    • Nuclei form
    • Chromosomes begin decondensing
  60. Meiosis II: Cytokinesis
    • Cytoplasm separates
    • Four daughter cells formed, each with haploid set of unreplicated chromosomes
  61. Sources of genetic variation among offspring
    • Independent assortment of chromosomes (meiosis)
    • Crossing over (meiosis)
    • Random fertilization (where sperm meets egg)
  62. Independetn assortment
    • every time we go through meiosis might give a diff arrangement
    • 1st place to get genetic diversity
  63. Crossing over
    • takes place in Prophase I
    • Inside chromosomes flip flop ends
    • 2nd place to get genetic diversity
  64. Random feritlization
    • Any sperm can fuse with any ovum
    • The fusion of 2 gametes (each with 8.4 milion possible chroosome combinations from independent assortment) produces a zygote with any of about 70 trillion diploid combinations
Card Set
Bio 12-14
Chapters over the cell cycle for BIO 120