Student Resource

This task is about using punnet squares to show genetic characteristics.
 
 
 
In humans, free ear lobes (E) are dominant while attached ear lobes (e) are recessive.
earlobes b&w.jpg
 
Free earlobe                             Attached earlobe 
 
a)
Matthew, who has attached ear lobes, and Nancy, who has free ear lobes, (her father had attached ear lobes) have four children.
The genotype of Nancy is Ee. 
LW1011 punnet square.jpg
What is the genotype of Matthew? Matthew's genotype:     __________
 
b) i)
Complete the punnet square to show the possible genotypes in their offspring:
 

 

 

  ii)
Of Matthew's and Nancy's four children, how many would be expected to have attached ear lobes?
 
__________