a) Coat color in rabbit:
The normal coat color is brownish grey which is dominant over other colors, i.e. Himalayan, Chinchilla and Albino.
The allele of C for full color is dominant over the allele Ch for Himalayan, Cch for Chinchilla and C for Albino). Allele Cch is dominant over the allele Ch and C while allele Ch is dominant over C thus allele c is recessive to the other three alleles.
Phenotypes – Genotypes
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Wild/full colored – CC, Cch Cch , Cc
Chinchilla – Cch ,Cch ,Cch ,ch ,cch,c
Himalayan – ch ,ch
Albino – cc
b) White eye in Drosophila:
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Morgan (1910) discovered a white eyed mutant in red eyed flies of Drosophila. Similarly, more than twelve mutations of the same locus have been reported i.e. white, ivory, pearl, tinged, buff, tann, apricot, cherry, eosin, blood, coral and red. C) Blood groups in man
When foreign protein is injected in the blood stream of an animal, a characteristic substance is produced which react with foreign protein.
The substance is called antibodies and foreign protein which produces antibodies is called antigens.
The relationship of antigens and antibodies is very specific and like key and lock. Each antigen is associated with particular antibodies.
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The process of introducing the blood of one person into the body of other is called transfusion. Dr. Karl Landsteiner (1900) discovered that when red blood cells of the person mixed with serum of another person, the agglutinization (clumping) occurs.
He discovered two antigens in human red blood cells and two corresponding antibodies. The antigens are A and B.
Out of these two antigens a person might have one in his cell or both or none. Thus human population can be divided into four groups.
Landsteiner recognized A, B and O blood groups while AB group was discovered in 1902 by Von Decastello and A. Sturli which can be explained on the basis of multiple alleles.
Person with a blood group ‘O’ could not receive blood from any other group but he may donate to any other group.
Hence, it is referred to universal donor. While person of blood group ‘AB’ is a universal recipient/acceptor since it contains no antibodies thus he can receive blood from A, B, AB or O group persons.
If donor’s blood has antibodies against that of recipient, it does not matter however, there should be no antibodies in recipient’s blood against donor’s blood. Since it would cause agglutinization of transfused blood.