What ratio is expected in offsprings if father is colour blind and mother's father was colour blind:
1. 50% daughter – colour blind
2. All the sons are colour blind
3. All the daughters colour blind
4. All the sons are normal
Among fraternal twins, one baby is haemophilic while the baby's brother is normal. Which statement is true:
1. Baby is male
2. Baby is female
3. Mother is heterozygous
4. Mother is homozygous
Minor change in a gene's structure is called:
1. Reversible mutation
2. Point mutation
3. Forward mutation
4. Backward mutation
According to Mendelism which character is showing dominance:
1. Terminal position of the flower
2. Green colour in the seed coat
3. Wrinkled seed
4. Green pod colour
Which of the following is the correct match:
1. Down Syndrome = 21st Chromosome
2. Sickel cell anaemia = X – Chromosome
3. Haemophilia = Y – Chromosome
4. Parkinson Disease = X & Y Chromosomes
Change in the sequence of nucleotides in DNA is called:
1. Mutagen
2. Mutation
3. Recombination
4. Translation
Which of the following is the example of a sex-linked disease:
1. AIDS
2. Colour blindness
3. Syphilis
4. Gonorrhoea
A gene is said to be dominant if:
1. | It expresses its effect only in the homozygous stage |
2. | It expresses only in heterozygous condition |
3. | It expresses both in homozygous and heterozygous conditions |
4. | It is never expressed in any condition |
Mangolian idiots are due to trisomy in the 21st chromosome is called:
1. Down's syndrome
2. Turner's syndrome
3. Kleinfelters syndrome
4. Triplex syndrome
In Drosophila the XXY condition leads to femaleness whereas in human beings the same condition leads to Klinefelter's syndrome in males. It proves:
1. | In human beings, the Y chromosome is active in sex determination. |
2. | Y chromosome is active in sex determination in both human beings and Drosophila. |
3. | In Drosophila Y-chromosome decides femaleness. |
4. | The Y chromosome of man has genes for the syndrome. |