Dystocia refers when a birth is difficult.
Crossing over between two chromosomes
Answer:
d. multiple alleles and codominance
Explanation:
ABO blood group is controlled by three alleles instead of the usual two. Hence, it is an example of multiple alleles. These three alleles are IA, IB and i. IAIA genotype leads to production of A antigen hence A blood group. IBIB genotype leads to production of B antigen hence B blood group. When they are present together (IAIB) both A and B antigens are produced resulting in AB blood group. Hence ABO blood group is also an example of codominance.
Both IA and IB are dominant over the i allele. So IAi and IBi will produce A and B blood group respectively. ii genotype leads to O genotype.
