1. | due to some defect like aspermia in man |
2. | due to the genetic makeup of the particular sperm which fertilizes the egg |
3. | due to the genetic makeup of the egg |
4. | due to some defect in the women |
1. | It confirms that DNA is the carrier of genetic information |
2. | It helps to understand whether the trait in question is dominant or recessive |
3. | It confirms that the trait is linked to one of the autosomes |
4. | It helps to trace the inheritance of a specific trait |
Which one of the following conditions of the zygotic cell would lead to the birth of a normal human female child?
1. one X and one Y chromosome
2. two X chromosomes
3. only one Y chromosome
4. only one X chromosome
The fruit fly Drosophila melanogaster was found to be very suitable for experimental verification of the chromosomal theory of inheritance by Morgan and his colleagues because:
1. | a single mating produces two young flies |
2. | smaller female is easily recognisable from a large male |
3. | it completes its life cycle in about two weeks |
4. | it reproduces parthenogenetically |
ABO blood grouping is controlled by gene I which has three alleles and shows co-dominance. There are six genotypes. How many phenotypes in all are possible?
1. | three | 2. | four |
3. | five | 4. | six |
Study the pedigree chart of a certain family given below and select the correct conclusion which can be drawn for the character:
1. | The parents could not have had a normal daughter for this character |
2. | The trait under study could not be colourblindness |
3. | The male parent is homozygous dominant |
4. | The female parent is heterozygous |
A cross in which an organism showing a dominant phenotype in crossed with the recessive parent in order to know its genotype is called:
1. Back cross
2. Test cross
3. Dihybrid cross
4. Monohybrid cross
In antirrhinum, two plants with pink flowers were hybridized. The F1 plants produced red, pink, and white flowers in the proportion of 1 red, 2 pink and 1 white. What could be the genotype of the two plants used for hybridization? Red flower colour is determined by RR, and White by rr genes.
1. | RR | 2. | Rr |
3. | rr | 4. | rrrr |