In two pea plants having red (dominant) coloured flowers with unknown genotypes are crossed, 75% of the flowers are red and 25% are white. The genotypic constitution of the parents having red coloured flowers will be 

(1) both homozygous

(2) one homozygous and other heterozygous

(3) both heterozygous

(4) both hemizygous

Genotypic and phenotypic ratios 1 : 2 : 1 in the offsprings explain the principle of 

(1) dominance

(2) blending inheritance

(3) recessiveness 

(4) All of the above

Sickle cell anaemia is example of 

(1) sex-linked inheritance

(2) deficiency disease

(3) autosomal heritable disease

(4) infectious disease

Holandric genes are located 

(1) both in X and Y-chormosome

(2) only in Y-chromosome

(3) only in X-chromosome

(4) only in autosomes

Which one of the following disorders and characteristic is correctly matched?

(1) Cystic fibrosis - Produciton of thick mucous that cloge airways

(2) Sickle cell anaemia - Brain deterioration beginning at months of age

(3) Achondroplasia - Extra fingers or toes

(4) Huntingon's disease - Skeletal, eye and cardiovascular defects

Tay-Sachs disease results due to lack of enzyme

(1) glucokinase

(2) hexosaminidase A

(3) Pyruvate kinase

(4) Na^- — K⁺ ATPase

A woman is married for the second time. Her first husband was ABO blood type A, and her child by that marriage was type O. Her new husband is type B and their child is type AB. WHat is the woman's ABO genotype and blood type ?

(1) I^AI^O; Blood type A

(2) I^AI^B; Blood type AB

(3) I^BI^O; Blood type B

(4) I^OI^O; Blood type O

Who is known as father of physiological genetics or father of biochemical genetics ?

(1) Slatyer

(2) Charles Elton

(3) Taylor

(4) Archibald Garrod

For how many years Gregor Mendel conducted hybridisation experiments on garden peas?

(1) 5

(2) 7

(3) 14

(4) 34

How many true breeding pea plant varieties had been selected by Mendel?

(1) 1

(2) 7

(3) 14

(4) 16