A gene has two alleles: the dominant allele (A), and the recessive allele (a). Two parents mate and each one independently contributes either a dominant allele or a recessive one. For each parent there is a 70% chance of contributing the dominant allele. If the parent does not contribute the dominant allele, then assume they contribute the recessive one.

1. Disease occurs if both parents contribute the recessive allele (aa). Find this probability.

1. 0.09
2. 0.49
3. 0.21
4. 0.51
5. 0.91

1. An offspring is said to be homozygous if both parents contribute the same allele. In other words, an offspring is homozygous if both parents contribute AA or aa. Find the probability that the offspring is heterozygous (i.e. not homozygous).

1. 0.09
2. 0.21
3. 0.42
4. 0.49
5. 0.91

1. Find the probability that an offspring is heterozygous or diseased.

1. 0.09
2. 0.21
3. 0.49
4. 0.51
5. 0.91