94 



Monohybrids 



10. Edmonds and Keeler report the inheritance of "pierced ears" in a 

 family from a small village in Italy. What does this family indicate as 

 to the mode of inheritance of this trait and the degree of penetrance of 

 the gene responsible? 



cTT] 



TK 



11. In the following family reported by S. E. Stoddard, the solid black 

 symbols indicate individuals in whom the Httle fingers of both hands are 

 flexed while the half-black symbols indicate persons with a flexed little 

 finger on the right hand. What is indicated as to the dominance, pene- 

 trance, and expressivity of the gene? 



4~ii-rO 



OriiioT^iiiiDri 



cTli 



6^ 



61] 



12. If you know of any persons with unusual traits that might be in- 

 herited, learn if you can, whether other members in the family (includ- 

 ing those no longer hving) show this trait. If the data are sufficient, 

 determine the mode of inheritance. 



