Haemophilia is
Autosomal
$Y$-linked
$Z$-linked
$X$-linked
Pedigree analysis is very important in human beings because
In the given pedigree, indicate whether the shaded symbols indicate dominant or recessive allele.
Study the given pedigree chart and select the correct option of the given question.
$(1)$ Is the trait recessive of dominant ?
$(2)$ is the trait sex linked or autosomal ?
Genes for colour blindness is carried by
$I.$ Abnormal development
$II.$ Father
$III.$ Mother
$IV.$ Autosomes
It is said, that the harmful alleles get eliminated from population over a period of time, yet sickle cell anaemia is persisting in human population. Why ?