Question

QUESTION 20 ne pedigree 2 pt Shown below is the free of a family, some of whose membershired green color bindness Who 50000 DO 000 TL DOO 1000 utosomal dominant se dominant autosomal receive

Answer 1

Ans: d) sex linked recessive.

The characteristics of sex linkef recessive inheritance are

Affected sons have carrier mother.

Affected daughters have affected father and carrier mother.

In the pedigree, in II generation all daughters are carrier but sons are normal. As daughters inherit their one X-chromosome from father and one from mother. Here in generation I, the father has affectted X chromosome , gives to his all daughters. The mother is normal so sons are unaffected in generation II as sons inherit their single X chromosome from mother. Carrier mother has one affected and one normal unaffected X chromosome so she can gives either one affected or one unaffected X chromosome to her son. Thats why carrier mother has affected or unaffected son but the fate of daughter depends on both parents. If daughther inherits both affected X chromosomes from parents only then she will be affected.