Polydactyly in humans is due to:

Select the correct match.

$A$ colour-blind man marries the daughter of a colour-blind person. Then in their progeny:

$A$ son of a colourblind father and a normal homozygous mother marries a daughter of a normal father and a heterozygous (carrier) mother. What will be the phenotype of their children?

Give differences: Mendelian disorders and Chromosomal disorders.

If both parents are carriers for thalassaemia,which is an autosomal recessive disorder,what are the chances of pregnancy resulting in an affected child?