Class 12th Biology 2018 Set1 Delhi Board Paper Solution
Question 15
Explain the mechanism of ‘sex determination’ in birds. How does it differ from that of human beings?
Answer
In birds, sex determination is of ZW-ZZ type.
In this type of homogametic and haven ZZ sex chromosomes and females are heterogametic with ZW pair of sex chromosomes.
Parents : Male X Female
ZZ ZW
Gametes : (Z) (Z) (Z) (W)
Tr : Female Male
Where as in humans,the chromosomal mechanism of sex determination is XX-XY type. The human male is heterogametic and have XY sex chromosome and human female is homogarnetie with XX sex chromosomes.
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