A cell at the telophase stage is observed by a student in a plant brought from the field. He tells his teacher that this cell is not like other cells at the telophase stage. There is no formation of a cell plate and thus the cell is containing more chromosomes as compared to other dividing cells. This would result in:
1. polyploidy
2. somaclonal variation
3. polyteny
4. aneuploidy
1. | Mutations destroy telomerase inhibitor |
2. | Mutations inactivate the cell control |
3. | Mutations inhibit the production of telomerase |
4. | Mutations in proto–oncogenes accelerate the cell cycle |
The movement of a gene from one linkage group to another is called:
An abnormal human baby with 'XXX' sex chromosomes was born due to:
1. formation of abnormal ova in the mother
2. fusion of two ova and one sperm
3. fusion of two sperms and one ovum
4. formation of abnormal sperms in the father
A man with blood group 'A' marries a woman with blood group 'B'. What are all the possible blood groups of their offspring?
Which one of the following symbols and its representation, used in the human pedigree analysis is correct?
1. | = Mating between relatives |
2. | = Unaffected male |
3. | = Unaffected female |
4. | = male affected |
If a chiasma forms between the loci of genes A and B in 20% of the tetrads of an individual of genotype AB/ab, the percentage of gametes expected to be Ab is:
1. 40
2. 20
3. 10
4. 5
Phenotype of an organism is the result of:
1. mutations and linkages
2. cytoplasmic effects and nutrition
3. environmental changes and sexual dimorpgism
4. genotype and environment interactions
Both sickle cell anaemia and Huntington’s chorea are:
1. bacteria-related diseases.
2. congenital disorders
3. pollutant-induced disorders
4. virus-related diseases
The dominant epistasis ratio is:
1. 9:3:3:1
2. 12:3:1
3. 9:3:4
4. 9:6:1