BIO Chp. 9

Card Set Information

BIO Chp. 9
2011-03-24 23:00:32
Biology Genetics Cell Division

Chapter 9 of the biology textbook that goes over genetics and cell division
Show Answers:

  1. DNA
    Contains an organism's genome
  2. Genome
    complete collection of an organism's genetic information.

    • -It's coade controls reproduction, development, and everyday functioning of living things
    • - a cell's 'recipe book'
    • -each individuual recipe = a gene
  3. Where are genomes stored?
    almost all DNA is stored in the nucleus

    -each cell has a copy of the entire genome
  4. What do DNA have instructions for?
    protein production: DNA has the instructions and makes proteins to actually carry out necessary tasks.

    -mainly enzymes
  5. How is the information in DNA stored?
    • encoded in chhemical substances
    • -Nitrogenous Bases
    • -4 different bases make DNA: ADenie, Thymine, Guanine, Cytosine
    • (A,T,G,C)

    sequence detemines genetic characteristics
  6. DNA stucture
  7. Protein Synthesis
    • -In the nucleus, DNA makes a copy of itself onto mRNA
    • -mRNA leaves nucleus, heads for a ribosome in the cytosol
    • -a string of amino acids are put together according to directions in mRNA
  8. Why do cells divide?
    • replace dead cells
    • for growth of an organism
    • -cells can only grow so big before they are dysfunctional
    • -therefore to grow, we need more (not BIGGER) cells
  9. What are the 3 components of cell division?
    • 1. Replication
    • 2.Mitosis
    • 3. Cytokinesis
  10. Replication
    Duplication of DNA
  11. Mitosis
    Separting DNA copies within the parent cell
  12. Cytokinesis
    Physical splitting of parent cell into 2 daughter cells
  13. Cell Division
  14. DNA replication
    • double helix unwinds
    • each strand serves as a template for constructing its new complementary strand
  15. Chromatin
    makes up chromosomes that DNA is packaged into.

    Chromatin = DNA + associated proteins
  16. Chromosomes
    Remain in an unduplicated state until DNA is replicated

    • Once DNA is duplicated, chromosomes become:
    • 2 identical sister chromatids
  17. Chromosomes and DNA replication
  18. What are the ways in which DNA can be found arranged?
    • unduplicated state: remains loose in the nucleus
    • duplicated: chromosomes consisiting of 2 identical sister chromatids take shape
  19. Matched Pairs
    • Chromosomes come in matched pairs
    • -one member of the pair in inherited from each parent
    • -they contain same genes but are NOT identical
    • -each pair: homologous chromosomes

    There are 46 chromosomes in humans, therefore 23 pairs
  20. The cell cycle
    • Interphase
    • Mitoctic Phase (M phase):

    • Interphase: cell is carrying out its job and preparing for cell division
    • Mitotic phase: includes mitosis and cytokinesis
  21. mitosis
    • how a cell divides.
    • This is a multi-step process
    • -prophase
    • -metaphase
    • -anaphase
    • -telophase
  22. Prophase
    • chromatin condenses into chromosomes
    • double structure formed-composed of 2 indentical sister chromatids
    • mitotic spindle begins to form
    • chromosomes migrate toward center of nucleus
    • nuclear envelope breaks down
  23. Mitosis
  24. metaphase
    • chromosomes line up on metaphase plate (attach to spindle fibers, microtubles)
    • sister chromatids uncouple into individual chromosomes
  25. Anaphase
    • spindle pulls separated chromatids to opposie spindle poles
  26. Telophase
    • spindle disassembles
    • nuclear envelope reforms
    • chromosomes decondense
  27. Cytokinesis
    • completes cell division by dividing the cytoplasm between the 2 daughter cells
    • cell furrows and splits in two
  28. Cell division in plant cells