11& 14

Card Set Information

11& 14
2010-12-12 15:22:57

Science Exam
Show Answers:

  1. What are gametes?
    • sex cells
    • male- sperm
    • female- eggs
  2. How many chromosomes are found in human gametets?
  3. What is synapsis? crossing over? chiasma?
    • Synapsis- The act of lining up side by side by homologous chromosomes during the meiotic phase of cell division
    • Crossing Over-when homologous chromosomes exchange DNA material

    When chromasomes created an "x" like structure
  4. How many daughter cells are produced from meiosis?
  5. What happens in prophase I, metaphase I, anaphase I, and telophase I?
    Prophase I-The first stage in the first meiotic division of meiosis. This stage is characterized by having five sub-stages namely leptotene, zygotene, pachytene, diplotene and diakinesis. It highlights the exchange of DNA between homologous chromosomes via a process called homologous recombination and the cross-over at chiasma(ta) between non-sister chromatids. Thus, this stage is important to increase genetic variation. This stage then ends with the disintegration of the nucleolus and the nuclear membrane.

    MetepahseI-Science: cell biology) The stage in the first meiotic division of meiosis that follows prophase I. Homologous chromosomes pair with each other to form tetrads of four chromatids and they align themselves along a single plane in the centre of the cell. Homologous recombination generally occurs during this stage. This stage ends as soon as the homologous chromosomes start being pulled away from each other, to opposite ends of the cell.

    Anaphase I-The pairs of homologous chromosomes are separated from each other and moved to opposite ends of the cell. This stage begins as soon as homologous chromosomes begin separating and ends when the chromosomes arrive at opposite ends of the cell.

    Telophase I-The stage in the first meiotic division of meiosis that follows anaphase I. The two sets of chromosomes have finished moving to opposite ends of the cell. Cytokinesis occurs, forming two daughter cells. Nuclear membranes do not form and the chromosomes do not decondense at this point, however, as they would in mitosis.
  6. Meiosis II is just like _______
  7. What is syngamy?
    The fusion of gametes resulting in the formation of a zygote, which develops into a new organism
  8. What is spermatogenesis and oogenesis? How do these processes differ?
    Spermatogenesis-The process occurring in the male gonad of sexually reproducing organism wherein the undifferentiated male germ cells develop into spermatocytes, which then transform into spermatozoa.

    Oogenesis-four daughter cells are created. Then one is determined the best one and eats the rest. then is fertilized by a sperm.

  9. How do gametes receive genetic variation?
    they get genes from both parents
  10. What is interkinesis?
    is similar to interphase except DNA synthesis does not occur.The events that occur during meiosis II are similar to mitosis.
  11. How do cells produced in meiosis compare to one another in terms of genetic content?
    They all differ because they recieve different genes thus no two look alike
  12. Know the processes that occur in Meiosis II
    same as mitosis
  13. Be able to identify pictures of meiosis (only two )
  14. what do the following terms mean?
    look on study guide
  15. what are the different types of chromosomal mutations
    sex-linked and autosomel
  16. be able to complete punnett squares
    no dihybrids and total of four. piece of cake
  17. karyotyping? Pedigree?
    • karyotyping- shows all of the homologous pairs of chromosomes.
    • Pedigree-shows all the offspring and their mutations.(normally shows one mutation and shows if the offspring are normal or not.)