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 the maize plant. When RRYY and rryy genotypes are hybridized, 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 a 3:1 ratio
4. higher number of the parental types
In pea plants, yellow seeds are dominant to green. If a heterozygous yellow-seeded plant is crossed with a green-seeded plant, what ratio of yellow and green-seeded plants would you expect in F1generation?
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
In which mode of inheritance do you expect more maternal influence among the offspring?
1. Autosomal
2. Cytoplasmic
3. Y-linked
4. X-linked
In Mendel's experiments with garden peas, round seed shape (RR) was dominant over wrinkled seeds (rr), and yellow cotyledon (YY) was dominant over green cotyledon (yy). What are the expected phenotypes in the F2 generation of the cross RRYY x rryy?
| 1. | Only round seeds with green cotyledons |
| 2. | Only wrinkled seeds with yellow cotyledons |
| 3. | Only wrinkled seeds with green cotyledons |
| 4. | Round seeds with yellow cotyledons and wrinkled seeds with yellow cotyledons |
If a colourblind woman marries a normal-visioned man, their sons will be:
1. all normal visioned
2. one-half colourblind and one-half normal
3. three-fourths colourblind and one-fourth normal
4. all colourblind
Cri-du-chat syndrome in humans is caused by the:
| 1. | fertilization of an XX egg by a normal y-bearing sperm |
| 2. | loss of half of the short arm of chromosome 5 |
| 3. | loss of half of the long arm of chromosome 5 |
| 4. | trisomy of 21st chromosome |
In Antirrhinum (Snapdragon), a red flower was crossed with a white flower and in F1 generation, pink flowers were obtained. When pink flowers were selfed, the F2 generation showed white, red, and pink flowers. Choose the incorrect statement from the following:
| 1. | Law of Segregation does not apply in this experiment. |
| 2. | This experiment does not follow the Principle of Dominance. |
| 3. | The pink colour in F1 is due to incomplete dominance. |
| 4. | Ratio of F2 is 1/4(red):2/4(pink):1/4(white). |
Select the incorrect statement:
| 1. | Human males have one of their sex-chromosome much shorter than the other. |
| 2. | Male fruit fly is heterogametic. |
| 3. | In male grasshoppers, 50% of sperms have no sex chromosome. |
| 4. | In domesticated fowls, the sex of progeny depends on the type of sperm rather than the egg. |