A pea plant parent having violet-coloured flowers with unknown genotype was crossed with a plant having white-coloured flowers. In the progeny, 50% were white. The genotypic constitution of the parent having violet-coloured flowers was

1. homozygous

2. merozygous

3. heterozygous

4. hemizygous

The number of linkage group(s) present in Escherichia coli is 

(1) One

(2) two

(3) four

(4) seven

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

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

Which one of the following best describe polygenic inheritance?

(1) ABO blood group in human and flower colour of Mirabilis jalapa

(2) Hair pigment of mouse and tongue rolling in humans

(3) Human eye colour and sickle-cell anaemia

(4) Human height and colour of skin and eyes