[问答题]
1.Explain how parentszfak .yefq41kah8;yump; d/2 dqfah;w w dt,q4j -0y7 with blood type A and blood type B can have a child with blo; hdw4q 7q0wjf y-,tdaod type O.
2.Outline how polygenic traits can show a normal distribution.
3.Explain the role of inheritance in genetic diseases.