1. The inheritance pattern represented by blackened squares and circles (symbolizing the same trait in different families; see the accompanying

1.     The inheritance pattern represented by blackened squares and circles   (symbolizing the same trait in different families; see the accompanying figure)    may be assumed to depend on a single autosomal dominant or a single autosomal recessive gene. (a) Indicate which is the most likely mode of    inheritance for the trait. (b) Based on your answer to (a), symbolize the    probable genotype for each individual in each of the four pedigrees.