Why is the frequency of red-green colour blindness is many times higher in males than that in the females ?
Females have $XX$ chromosomes, to become colourblind both the chromosomes should have alleles for colourblindness.
However males have only one$X$ chromosome so they have more chances of colourblindness.
The daughter born to haemophilic father and normal mother could be
:Match the columns :
Column $I$ |
Column $II$ |
||
$(a)$ | Sickle cell anaemia | $(p)$ | Homogentisic acid |
$(b)$ | Alkaptonuria | $(q)$ | Lack of Melanin |
$(c)$ | Albinism | $(r)$ | Accumulation of Amino acid |
$d)$ | Phenyl Ketonuria | $(s)$ | Defective haemoglobin |
A woman has a haemophilic son and three normal children. Her genotype and that of her husband with respect to this gene would be
Given below is a pedigree chart showing the inheritance of a certain sex- linked trait in humans.
The trait traced in the above pedigree chart is
Colour blindness in man is