Sometimes the separation of twins is incomplete and these are borne attached are remain so even after. Such twins are known as
Fraternal
Dizygotic
Identical
Siamese
Sex chromosomes of a female bird are represented by
It is easier to study polygenic inheritance of characters in plants than in animals because in the plants
All the sons are haemophilic and daughter are normal of a haemophilic father and normal mother. This character is
The loss of chromosomal segment is due to