Name____________________________________ Date________________ Hour________________

GENETICS COMPUTER SIMULATIONS - MENDELISM

GENETICS CD - 3

Directions: Obtain a CD entitled "Biology Explorer 3.04 Genetics" and a coin from your instructor. Go quietly to the Media Center computer lab. Insert the CD and then complete the following activity. Return the CD to your instructor when finished.

PURPOSE: To discover the principle of dominance by simulating the crosses performed by Gregor Mendel.

PROCEDURE:

    1. Go to the START MENU.
    2. Place your cursor on PROGRAMS.
    3. Move your cursor to "LOGAL Biology Teacher."
    4. Click on GENETICS MAIN MENU.
    5. Click on "EXPLORATIONS."
    6. Click on "MENDALISM."
    7. <<At this point, the arrows to move around through the program are at the very bottom of the screen. We may have to grab and drag the Start menu tool bar downward until we can’t see it any longer in order to uncover the arrows we need.>>
    8. Follow the directions on each page to complete the exercise. Blue "hyperlinked" words in the directions text can be clicked on to perform certain functions.

QUESTIONS AND DATA TABLES:

  1. What is that trait and what are its variations? The trait:__________________________

    2. The trait variation of couple #1: ______________________ The trait variation of couple #2: ________________________

  2. How many variations do you see in the F1 offspring? __________________________
  3. How does this compare with the trait variation of the parents, couple #1? ________________________________________________
  4. What is the number of trait variations in the F2 offspring? __________________________
  5. How does this compare with the trait variation of their parents (the F1 offspring?) ___________________________________________
  6. What is the number of trait variations in the F1 offspring? __________________________
  7. How does this compare with the trait variation of their parents, couple #2? ________________________________________________
  8. What is the number of trait variations in the F2 offspring? __________________________
  9. How does this compare with the trait variation of their parents (the F1 offspring?) ___________________________________________
  10. Based on what you’ve seen, how might you characterize the line of generations, beginning with couple #1, with respect to the trait you are testing?

    11.  

     

  11. How might you characterize the line descending from couple #2?

    12.  

     

  12. How might you characterize the individuals in each line?

    13.  

     

    13. What trait variation or variations for ear position do you think will appear in the F1 generation? ________________________________

  13. Describe the ear position (s) you see in the offspring and compare with the parents. Do you u see ears that are intermediate in form?

    14.  

     

  14. What do you find puzzling about the F1 offspring as compared with their parents?
  15. Data table number one: [this table will be used on pages 13, 16, and 17.]
    16.

    PAIR NO.

    ID NO. OF F1 MALE

    ID NO. OF F1 FEMALE

    TRAIT VARIATION(S) IN THE F2 OFFSPRING

    1

    2

    3

  16. How many types of ears do you see in the F2 generation now? __________________________
  17. What is really puzzling about this?

    18.  

  18. Could it be that your surprising outcome in the F2 generation is a result of the specific F1 parents you chose? _____________________
  19. Based on these results, <<from data table one>> is the event you observed after the first trial an isolated event or does it apply generally in the F2 generation?

    20.  

  20. To summarize, describe the "living puzzle" you have observed, in terms of the parents, P, and the F1 and F2 generations.

    21.  

  21. Can you suggest and explanation for these surprising observations?

    22.  

     

  22. How do your simulations from the previous sections compare with Mendel’s experimental strategy?

    23.  

     

  23. Did a trait variation found in one of the parents disappear in the F1 offspring? __________________________
  24. If so, what was this trait variation? __________________________
  25. Was this variation actually "lost?" How can you tell? (recall the F2 offspring…)
  26. If this trait variation wasn’t actually lost, how might you explain the observation that this variation disapeared in the F1 offspring?

    27.  

  27. In the F1 generation in your simulation, which trait variation could be called dominant? __________________________
  28. Which trait variation could be called recessive? __________________________
  29. Data table two:
    30.

    TYPE OF ALLELE

    SYMBOL

    TRAIT VARIATION

    DOMINANT

    A

    RECESSIVE

    a

  30. Considering your answers in this section, how many alleles are carried by an individual for each trait? __________________________
  31. What were the genotypes and phenotypes of the individuals in the P generation used for the parental (PXP) cross in "The Living Puzzle?"
  32. Data table three:

THE F1 GENERATION

GENOTYPE

PHENOTYPE

33. With what you now know, offer a hypothesis which explains "The Living Puzzle."