Cell division

Cards (59)

  • Asexual reproduction
    Mother cell -> daughter cell
  • Multicellular eukaryotes
    • Growth/development
    • Tissue renewal
  • Cell cycle
    1. Interphase (3 phases)
    2. Mitosis (5 phases)
    3. Cytokinesis
  • Interphase
    1. G1 (cell physically grows, prepares for DNA replication)
    2. S (copying DNA)
    3. G2 (cell finishes growing, makes microtubules)
  • Mitosis
    1. Prophase (DNA packs into visible chromosomes, microtubules assemble)
    2. Prometaphase (nuclear envelope breaks down, microtubules attach to chromosomes)
    3. Metaphase (chromosomes line up at equatorial plate)
    4. Anaphase (sister chromatids separate and move to poles)
    5. Telophase (chromosomes decondense, nuclear envelope reforms)
  • Chromosome
    Packaged and structured DNA molecule
  • Centromere
    Holds the sister chromatids together
  • Kinetochore
    Attachment site for microtubules (spindle fibers)
  • Cleavage furrow
    Pinched area where cell divides
  • Cytokinesis
    Physical division of cytoplasm to form 2 independent cells
  • Cell cycle checkpoints
    • G1 (DNA change, enough food, growth signal)
    • G2 (cell size, DNA copied properly)
    • M (all microtubules attached to sister chromatids)
  • Tumor suppressor genes
    Involved in inhibiting (stopping) cell cycle (cell growth)
  • Proto-oncogenes
    Genes involved in promoting cell cycle
  • Ploidy
    Number of sets of chromosomes
  • Diploid
    2 sets of chromosomes (1 from maternal, 1 from paternal)
  • Haploid
    1 set of chromosomes
  • Homologous chromosomes
    Matching pair of chromosomes (similar in genetic content)
  • Autosomes
    Not a sex chromosome (1-22)
  • Sex chromosomes
    X and Y, determine biological sex (XX female, XY male)
  • Sexual reproduction
    2 parents produce offspring (fusion of gametes)
  • Meiosis
    Reductive cell division for production of gametes
  • Germ cell

    Diploid cell (starting cell for meiosis) that undergoes meiosis
  • Gamete
    Haploid sex cell (sperm or egg)
  • Why is meiosis reductive? When gametes fuse it results in proper number of chromosomes in zygote (offspring)
  • Meiosis
    1. Interphase
    2. Meiosis 1
    3. Meiosis 2
  • Prophase 1
    1. Synapsis (homologous chromosomes pair up)
    2. Recombinant chromatids (crossing over of DNA)
    3. Chiasma (location of crossing over)
  • Crossing over results in greater diversity in gametes
  • Tetrads
    Pair of homologous chromosomes, 4 sister chromatids
  • Metaphase 1
    Tetrads line up along metaphase plate
  • Anaphase 1
    Homologous chromosomes pulled apart to opposite poles
  • Telophase 1

    Cleavage furrow forms, nuclear envelope reforms
  • Prophase 2
    Nuclear envelope breaks down, spindle begins to form
  • Metaphase 2
    Chromosomes align in the middle, spindle fibers connect to kinetochores
  • Anaphase 2
    Sister chromatids separate
  • Telophase 2
    Nuclear envelope reforms, cytokinesis begins
  • Independent assortment increases genetic diversity
  • Why are cells haploid? One DNA replication and two cell division events
  • Scientists involved in discovery of DNA double helix structure
    • Watson
    • Franklin
    • Crick
    • Wilkins
    • Chargaff
  • Semiconservative DNA replication
    Parent DNA molecule serves as template, final "daughter" DNA molecules have mix of original and new strands
  • Prokaryotic genomes

    One circular chromosome, one origin of replication (ori)