BioLab 10 - Taster or Not

A gene, located on chromosome 7, is responsible for tasting phenylthiocarbamide (PTC). If a person has two of these genes, PTC tastes very bitter. If only one gene is present, PTC has a slightly bitter taste. If a person does not have this gene on either of the homologous chromosomes, PTC has no taste at all.

For this lab, you will be given two paper strips. One of these, the control, has not been treated with PTC - the other has.

    Place the control strip on your tongue. All you taste is the paper. From this, you will be able to judge the taste of the PTC paper.
     
  1. Place the PTC strip on your tongue.
     
  2. Record your result by putting a check in the appropriate column of Table 1.
     
    Individual PTC Taste Results   (Table 1)
    Very Bitter
    (2 genes)    		 Slightly Bitter
    (1 gene)    		 No Taste
    (0 genes)
         
  3. What can be said about this gene in your parents?
     
     
     
     
  4. Record the class totals in table 2.

    Class Totals   (Table 2)
    Very Bitter Slightly Bitter No Taste "Tasters"
    (Very Bitter + Slightly Bitter)    		 "Non-tasters"
    (No Taste)
             
     

  5. This class is __________% "Tasters".   (Tasters/total in class) X 100
     

  6. This class is __________% "Non-tasters".   (Non-tasters/total in class) X 100
 

Conclusion:   70% of the U.S. population are tasters. How does the class compare to that percentage?