Types of gametes produced by a homozygous parent

(1) many

(2) single type

(3) depends upon number of genes

(4) depends upon number of chromosomes

If a man consists of an extra copy of chromosome number 18, then the condition is known as

1. Monosomy

2. Trisomy

3. Nullisomy

4. Polyploidy

Disorder caused by the trisomy of chromosome number 21

(1) Klinefelter’s syndrome

(2) Turner’s syndrome

(3) Down’s syndrome

(4) Phenylketonuria

Down’s syndrome was first described in the year

(1) 1962

(2) 1866

(3) 1856

(4) 1863

Gynaecomastia refers to

1. Masculine development in females

2. Development of breasts in males

3. Development of female characters in male

4. Reduced breasts in the female

In humans karyotype of 47, XXY leads to  

(1) Klinefelter’s syndrome

(2) Turner’s syndrome

(3) Down’s syndrome

(4) Edward’s syndrome

Furrowed tongue and partially open mouth are characteristics of

(1) Edward’s syndrome

(2) Turner’s syndrome

(3) Down’s syndrome

(4) Klinefelter’s syndrome.

Choose the correct match:

1. i-c,d; ii-b,e,f; iii-a

2. i-e,c; ii-b,f; iii-a,d

3. i-a; ii-b,e,f; iii-c,d

4. i-a,c; ii-d,e; iii-b,d

Turner’s syndrome is caused by

(1) Absence of Y chromosome

(2) Absence of one of the ‘X’ chromosome

(3) Trisomy of chromosome number 21

(4) Additional copy of chromosome ‘X’.

What will be the ratio of homozygous dominant, homozygous recessive and pure heterozygous traits in F₂ generation in pea plant is

(1) 1 : 1 : 8

(2) 2 : 3 : 2

(3) 1 : 1 : 2

(4) 2 : 2 : 6