A woman receives her X chromosomes from:
1. her mother only
2. her father only
3. both her mother and her father
4. extranuclear DNA in her mother's egg
Sickle cell anaemia has not been eliminated from the African population because:
1. It is controlled by recessive genes
2. It is not a fatal disease
3. It provides immunity against malaria
4. It is controlled by dominant genes
What map unit (Centimorgan) is adopted in the construction of genetic maps?
1. | A unit of distance between genes on chromosomes, representing 50% cross-over. |
2. | A unit of distance between two expressed genes, representing 10% cross-over. |
3. | A unit of distance between two expressed genes, representing 100% cross-over. |
4. | A unit of distance between genes on chromosomes. representing 1% cross-over. |
The inheritance of flower colour in dog flower and 4’O clock plant exhibits:
1. | Complete dominance | 2. | Incomplete dominance |
3. | Co-dominance | 4. | Lethality |
Occasionally, a single gene product may produce more than one effect. Such a gene is said to be:
1. | Pleiotropic | 2. | Polygenic |
3. | Psuedoallele | 4. | Housekeeping |
The mechanism of sex determination in grasshoppers is:
1. | XX – XY; male heterogamety |
2. | XX – XY; female heterogamety |
3. | XX – XO; male heterogamety |
4. | XX – XO; female heterogamety |
A plant, on repeated self-pollination, preserves the trait expressed for many generations. Such a plant is said to be:
1. | Panmictic | 2. | Homologous |
3. | Apomictic | 4. | Pure line |
What is the F2 phenotypic ratio in cases of incomplete dominance?
1. | 1 : 1 | 2. | 3 : 1 |
3. | 1 : 2 : 1 | 4. | 1 : 1 |
The famous double helix model of DNA was proposed by Watson and Crick in ____ and they shared Nobel Prize for Physiology or Medicine in ________ for their effort.
1. | 1951, 1971 | 2. | 1943, 1963 |
3. | 1953, 1962 | 4. | 1969, 1972 |
Which of the following is a recessive trait for a character chosen by Mendel in garden pea?
1. | Violet flower colour | 2. | Yellow pod colour |
3. | Axial flower position | 4. | Tall stem height |