+91-8076753736 support@wiredfaculty.com
logo
logo

Sponsor Area

Principles Of Inheritance And Variation

Question
CBSEENBI12001897
Wired Faculty App

(a) Explain the phenomena of multiple allelism and co-dominanace taking ABO blood group as an example.

(b) What is the phenotype of the following:

(i) IAi

(ii) i i

Solution

(a) The inheritance of ABO blood groups in humans exhibits co-dominance and multiple allelism.

Multiple allelism-: The ABO blood groups are controlled by the gene I. The I gene has three alleles, namely IA, IB and i. Since more than two alleles control a single trait thus it shows multiple allelism.

Co-dominance-: The allele IA and IB are both dominant over the allele i but they express themselves completely even in the presence of the other that is when both are present the blood group is AB . This represents co-dominance.

(b) ( i) Phenotype of IAi will be A blood group since the allele IA is dominant over the allele i

(ii) Phenotype of ii will be O blood group since the allele is recessive and expresses itself in the homozygous condition.

Some More Questions From Principles of Inheritance and Variation Chapter

Write down Mendel’s dihybrid Phenotypic ratio 

Who were the rediscoverers of Mendelism ?

What are the real determinants of what an organism will become ?

What is the unique feature of F1 generation ?

What will be the genetic make up of an organism which suffers from sickle cell anaemia ?

What do the symbols square and circle in a pedigree chart indicate ?

Define heterogamy. Give an example.

How many chromosomes are found in human cells ?

Why is male Drosophila regarded as heterogametic ?

What term is used for the two chromatids resulting from the interchange of segments during crossing over ?

Mock Test Series

Mock Test Series

NCERT Sample Papers

Entrance Exams Preparation