Student Version


Name: ____________________________    Date: ________________

Exploration of Human Species:  A computer simulation of the classic introductory high school activity in human genetics.

GenScope Files:  Human

Now that you have had time to learn about GenScope tools and the Dragon species, it's time to look at a few common Human traits and figure out the rules governing their inheritance.  Although these traits are shown on specific chromosomes, you should be aware that the actual sites for the genes is unknown at this time.  In other words, we just made ╬em up!  But the mode of inheritance of these traits is known and has been integrated into the GenScope program.

To begin, start GenScope with the Human species file.

1.       Look at some of the traits.  Click on the magnifying glass at the ORGANISM level.  Hold your cursor over the spots on the human figures.  These spots are "hot spots" - which means that when you place the magnifying glass on top of one of the circles, you will get a picture of what the trait looks like.  Examples:  an enlarged picture of a cheek, a thumb, and earlobe, a chin or a hairline will appear.

2.       Your job is to figure out how each trait is inherited.  You can use the chromosome tool if you like to explore.  Fill out the table below with the alleles for each trait.

Trait Homozygous Dominant (TT) Heterozygous (Tt) Homozygous recessive (tt)
Widow's Peak      
Ear lobes      
Cleft Chin      
Hitchhiker's Thumb      
Polydactyly (extra fingers)      
Now, using the information that you have gathered and put in the above table, write a rule for how each of the traits is inherited. For example, if you were talking about the wings trait in dragons, the rule for wings would be W_ (meaning WW or Ww) is "Has no wings" and ww is "Has wings". Wingless (has no wings) is dominant to wings.
  1. Widow's Peak:

2. Dimples:

3. Ear lobes:

4. Cleft Chin:

5. Hitchhiker's Thumb:

6. Polydactyly (Extra digit):

Were any of these traits sex linked?

How do you know?

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