The affected male in the pedigree chart is symbolised by

In pedigree analysis,the symbol given for sex unspecified is

In the given pedigree,indicate whether the shaded symbols indicate a dominant or recessive allele.

$A$ normal-visioned man whose father was colour-blind,marries a woman whose father was also colour-blind. They have their first child as a daughter. What are the chances that this child would be colour-blind?

Who is known as the father of human genetics?

Which of the following diseases is known as a 'bleeder's disease',caused by the presence of an $X$-linked recessive gene?