One gene – one enzyme hypothesis was postulated by

• R. Franklin

• Hershey and Chase

• A. Garrod

• A. Garrod

Test cross involves

• crossing between two genotypes with recessive trait

• crossing between two F₁ hybrids

• crossing the F₁ hybrid with a double recessive genotype

• crossing the F₁ hybrid with a double recessive genotype

If a colourblind woman marries a normal visioned man, their sons will be

• all normal visioned

• one-half colourblind and one-half normal

• three-fourths colourbling and one-fourth normal

• three-fourths colourbling and one-fourth normal

Sickle cell anaemia has not been eliminated from the African population because

• it is controlled by recessive genes

• it is not a fatal disease

• it provides immunity against malaria

• it provides immunity against malaria

Both sickle cell anaemia and Huntington's chorea are

• bacteria-related diseases

• congenital disorders

• pollutant-induced disorders

• pollutant-induced disorders

A disease caused by an autosomal primary non-disjunction is

• Down's syndrome

• Klinefelter's syndrome

• Turner's syndrome

• Turner's syndrome

The genotypes of a Husband and Wife are I^AI^B and I^Ai. Among the blood types of their children, how many different genotypes and phenotypes are possible?

• 3 genotypes ; 3 phenotypes

• 3 genotypes ; 4 phenotypes

• 4 genotypes ; 3 phenotypes

• 4 genotypes ; 3 phenotypes

68.

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

• Stem – Tall or Dwarf

• Trichomes – Glandular or non-glandular

• Seed – Green or Yellow

• Seed – Green or Yellow

Which one from those given below is the period for Mendel's hybridization experiments?

• 1856 - 1863

• 1840 - 1850

• 1857 - 1869

• 1857 - 1869

Which of the following characteristics represent ‘Inheritance of blood groups’ in humans?

a. Dominance
b. Co-dominance
c. Multiple allele
d. Incomplete dominance
e. Polygenic inheritance

• b, c and e

• a, b and c

• a, c and e

• b, d and e