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 |
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 |
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
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 |
Represented below is the inheritance pattern of a certain type of traits in humans. Which one of the following conditions could be an example of this pattern?
1. | Sickle cell anemia | 2. | Haemophilia | |
3. | Thalassemia | 4. | Phenylketonuria |
A test cross is carried out to:
1. | Predict whether two traits are linked |
2. | Assess the number of alleles of a gene |
3. | Determine whether two species or varieties will breed successfully |
4. | Determine the genotype of a plant at F2 |
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 |