Principles of Inheritance and Variation

A diseased man marries a normal woman. They get three daughters and five sons. All the daughters were diseased and sons were normal. The gene of this disease is : -

1. Sex linked dominant
2. Autosomal dominant
3. Sex linked recessive
4. Sex limited character

Which of the following is a correct match -

1. Sickle cell anaemia = X – Chromosome
2. Down Syndrome = 21st Chromosome
3. Haemophilia = Y – Chromosome
4. Parkinson Disease = X & Y Chromosome

Change in sequence of nucleotide in DNA is called as -

1. Recombination
2. Mutation
3. Mutagen
4. Translation

If a diploid cell is treated with colchicine then it becomes : -

1. Tetraploid
2. Monoploid
3. Diploid
4. Triploid

Two non-allelic genes produce the new phenotype when present together but fail to do so independently then it is called

1. Polygene
2. Complementary gene
3. Non-complementary gene
4. Epistasis

A and B genes are linked. What shall be genotype of progeny in a cross between AB/ab and ab/ab?

1. AABB and aabb
2. None
3. AaBb and aabb
4. AAbb and aabb

When dominant and recessive alleles express themselves together it is called

1. Dominance
2. Pseudo dominance
3. Co-dominance
4. Amphidominance

Ratio of complementary genes is

1. 9 : 3 : 4
2. 9 : 7
3. 12 : 3 : 1
4. 9 : 3 : 3 : 4

Independent assortment of genes does not take place when

1. Genes are located on non-homologous chromosomes
2. Genes are linked and located on same chromosome
3. Genes are located on homologous chromosomes
4. All the above

Sickle cell anaemia is due to

1. Change of amino acid in either or chain of haemoglobin
2. Change of amino acid in chain of haemoglobin
3. Change of amino acid in both and chain of haemoglobin
4. Change of amino acid in chain of haemoglobin

Number of Barr bodies in XXXX female is

1. 3
2. 1
3. 2
4. 4

Male XX and female XY sometime occur due to

1. Aneuploidy
2. Deletion
3. Transfer of segments in X and Y chromosomes
4. Hormonal imbalance

Probability of four sons to a couple is : -

1. 116
2. 18
3. 14
4. 132

Due to the cross between TTRr × ttrr the resultant progenies showed how many percent plants tall, red flowered:

1. 50%
2. 100%
3. 75%
4. 25%

According to mendelism which character is showing dominance?

1. Green colour in seed coat
2. Wrinkled seed
3. Terminal position of flower
4. Green pod colour

Mongolian idiots are due to trisomy in 21st chromosome is called:

1. Klinefelter's syndrome
2. Down's syndrome
3. Turner's syndrome
4. Triplex syndrome

Erythroblastosis foetalis is caused when:

1. Rh- female & Rh+ male
2. Rh- female & Rh- male
3. Rh+ female & Rh+ male
4. Rh+ female & Rh- male

In Drosophila the XXY condition leads to femaleness whereas in human beings the same condition leads to Klinefelter's syndrome in male. It proves:

1. Y chromosome is active in sex determination in both human beings and Drosophila
2. In Drosophila Y-chromosome decides femaleness
3. Y chromosome of man have genes for syndrome
4. In human beings Y chromosome is active in sex determination