In humans, the dominance relationship between the A and B alleles of ABO blood group gene is an example of

(1) complete dominance.

(2) incomplete dominance.

(3) codominance.

(3) epistasis

 

One of the Mendel's pure strains of pea plants had green peas. How many different types of eggs could such a plant produce with regard to pea color?

1. 1

2. 2

3. 4

4. 8

A woman receives her X chromosomes from:

1. Her mother only

2. Her father only

3. Both her mother and father 

4. Mitochondria of mother only

Which one from those given below is the period of Mendel's hybridisation experiments?

(1) 1856 - 1863

(2) 1840 - 1850

(3) 1857 - 1869

(4) 1870 - 1877

Among the following characters, which one was not considered by Mendel in his experiments on pea?

(1) Stem - Tall or Dwarf

(2) Trichomes - Glandular or Non-glandular

(3) Seed - Green or Yellow

(4) Pod - Inflated or Constricted

Thalassemia and sickle-cell anaemia are caused due to a problem in globin molecule synthesis. Select the correct statement.

(1) Both are due to a qualitative defect in globin chain synthesis

(2) Both are due to a quantitative defect globin chain synthesis

(3) Thalassemia is due to less synthesis of globin molecules

(4) Sickle-cells anaemia is due to a quantitative problem of globin molecules

A disease caused by an autosomal primary non-disjunction is 

(1) Down's syndrone

(2) Kilnerfelter's syndrome

(3) Turner's syndrome

(4) Sickle-cell anemia

The mechanism that causes a gene to move from one linkage group to another is called 

(1) inversion

(2) duplication

(3) translocation

(4) crossing-over

If a colourblind man marries a woman who is homozygous for normal colour vision, the probalility of their son being colourblind is 

(1) 0

(2) 0.5

(3) 0.75

(4) 1

A tall true breeding garden pea plant is crossed with a dwarf true breeding garden pea plant. When the F₁ plants were selfed the resulting genotypes were in the ratio of 

(1) 1 : 2 : 1 :: Tall heterozygous : tall homozygous : Dwarf

(2) 3 : 1 :: Tall : Dwarf

(3) 3 : 1 :: Dwarf : Tall

(4) 1 : 2 : 1 :: Tall homozygous : Tall heterogygous : Dwarf