321. An example of gene therapy is
A
Production of injectable Hepatitis-B vaccine
B
Production of vaccines in food crops like potatoes which can be eaten
C
Introduction of gene for adenosine deaminase in persons suffering from severe combined immuno-deficiency (SCID)
D
Production of test tube babies by artificial insemination and implantation of fertilized eggs
Answer :
Introduction of gene for adenosine deaminase in persons suffering from severe combined immuno-deficiency (SCID)
322. Molecular weight of chromosome of yeast cell is
A
2.56 × 109
B
40 × 109
C
0.5 × 109
D
1 × 109
Answer :
2.56 × 109
323.
Study the pedigree chart given below:
What does it show?
A
Inheritance of a condition like phenylketonuria as an autosomal recessive trait
B
The pedigree chart is wrong as this is not possible
C
Inheritance of a recessive sex - linked disease like haemophilia
D
Inheritance of a sex-linked inborn error of metabolism like phenylketonuria
Answer :
Inheritance of a condition like phenylketonuria as an autosomal recessive trait
324. Short-legged variety variety of sheep is an example of
A
Recesive germinal mutation
B
Dominate germinal mutation
C
Recessive somatic mutation
D
Dominant somatic mutation
Answer :
Dominate germinal mutation
325. In Mendel's experiments with garden pea, round seed shape (RR) was dominant over wrinkled seeds (rr), yellow cotyledon (YY) was dominant over green cotyledon (yy). What are the expected phenotypes in the F2 generation of the cross RRYY x rryy
A
Only round seeds with green cotyledons
B
Only wrinkled seeds with yellow cotyledons
C
Only wrinkled seeds with green cotyledons
D
Round seeds with yellow cotyledons, and wrinkled seeds with yellow cotyledons
Answer :
Round seeds with yellow cotyledons, and wrinkled seeds with yellow cotyledons
326. The phenomenon in which an allele of one gene suppresses the expression of an allele of another gene is known as
A
Dominance
B
Inactivation
C
Epistasis
D
Suppression
Answer :
Epistasis
327. Ratio of complementary genes
A
9 : 3 : 4
B
12 : 3 : 1
C
9 : 3 : 3 : 4
D
9 : 7
Answer :
9 : 7
328. Phenotype of an organism is the result of
A
cytoplasmic effects and nutrition
B
environmental changes and sexual dimorphism
C
genotype and environment interactions
D
mutations and linkages
Answer :
genotype and environment interactions
329. Who postulated the 'Chromosome Theory of Inheritance'
A
De Vries
B
Mendel
C
Sutton and Boveri
D
Morgan
Answer :
Sutton and Boveri
330. A useful process for determining whether an individual is homozygous or heterozygous is
A
Cross-breeding
B
Self fertilization
C
Back - crossing
D
Test cross
Answer :
Test cross