Which one of the following condition in human is correctly matched with its chromosomal abnormality/linkage?

(1) Klinefelter's syndrome—44 autosomes + XXY

(2) Colourblindness —Y-linked

(3) Erythroblastosis foetalis— X-linked

(4) Down syndrome—44 autosomes + XO

 

A human male produces sperms with the genotypes AB, Ab, aB and ab pertaining to two diallelic characters in equal proportions. What is the corresponding genotype of this person ?

(1) AaBb

(2) AaBB

(3) AABb

(4) AABB

In the hexaploid wheat, the haploid (n) and basic (x) numbers of chromosomes are:

1. n = 7 and x = 21

2. n = 21 and x = 21

3. n = 21 and x = 14

4. n = 21 and x = 7

Inheritance of skin colour in humans is an example of :

(1) chromosomal aberration

(2) point mutation

(3) polygenic inheritance 

(4) codominance

Two genes R and Y are located very close on the chromosomal linkage map of maize plant. When RRYY and rryy genotypes are hybridised, then F₂ segregation will show :

(1) higher number of the recombinant types

(2) segregation in the expected 9 : 3 : 3 : 1 ratio

(3) segregation in 3 : 1

(4) higher number of the parental types

A common test to find the genotype or hybrid is by :

(1) crossing of one F₂ progeny with male parent

(2) crossing of one F₂ progeny with female parent

(3) studying the sexual behaviour of F₁ progenies

(4) crossing of one F₁ progeny with recessive parent

In pea plants, yellow seeds are dominant to green. If heterozygous yellow seeded plant is crossed with a green seeded plant, what ratio of yellow and green plants would you expect in F₁ generation ?

(1) 50 : 50

(2) 9 : 1

(3) 1 : 3

(4) 3 : 1

Which one of the following is the most suitable, medium for culture of Drosophila melanogaster ?

(1) Moist bread

(2) Agar agar

(3) Ripe banana

(4) Cow dung

Phenotype of an organism is the result of :

(1) mutations and linkages

(2) cytoplasmic effects and nutrition

(3) environmental changes and sexual dimorphism

(4) genotype and environmental interactions.

In which mode of inheritance do you expect more maternal influence among the offspring ?

(1) Autosomal

(2) Cytoplasmic

(3) Y-linked

(4) X-linked