Procedure FIGURE 1 marriage Line 1 1 2 children line Part A. Background Information The pedigree in Figure I shows the pattern of inheritance in a family for a specific trait. The tait being showa is earlobe shape. Geneticists recognize two general earlobe shapes, free lobes and attached lobes (Figure 2). The gene respon- sible for free lobes (E) is dominant over the gene for attached lobes (e). In a pedigree, each generation is represented by a Roman numeral. Each person in a generation is mumbered. Thus each person can beidentified by a generation numeral and individual number. Males are represented by squares whereas females are represented by circles. 1 2 3 FIGURE 2 Part B. Reading a Pedigree In Figure I, persons l-1 and 1-2 are the parents. The line which connects them is called a marriage line. Persons II-I, 2, and 3 are their children. The line which extends down from the marriage line is the children line. The children are placed left to right in order of their births. That is, the oldest child is always on the left. R free lobe attached lobe 1. What sex is the oldest child?
2. What sex is the youngest child?