Incomplete (partial or mosaic) dominance is the phenomenon where none of the two contrasting alleles or factors is dominant. The expression of the character in a hybrid or F₁ individual is intermediate or a fine mixture of the expression of the two factors (as found in homozygous state). Incomplete or mosaic inheritance is not an example of premendelian concept of blending inheritance because the parental types reappear in the F₂ generation. It is however, considered by some workers to be an example of quantitative inheritance where only a single gene pair is involved. F₂ phenotypic ratio is 1: 2: 1, similar to genotypic ratio.

Correct Option: D

Incomplete (partial or mosaic) dominance is the phenomenon where none of the two contrasting alleles or factors is dominant. The expression of the character in a hybrid or F₁ individual is intermediate or a fine mixture of the expression of the two factors (as found in homozygous state). Incomplete or mosaic inheritance is not an example of premendelian concept of blending inheritance because the parental types reappear in the F₂ generation. It is however, considered by some workers to be an example of quantitative inheritance where only a single gene pair is involved. F₂ phenotypic ratio is 1: 2: 1, similar to genotypic ratio.

Heterosis or hybrid vigor occurs when two unrelated individuals or lines are crossed, the performance of F₁ hybrid, which is often superior to both is parents.

Correct Option: A

Heterosis or hybrid vigor occurs when two unrelated individuals or lines are crossed, the performance of F₁ hybrid, which is often superior to both is parents.

Type O blood group is considered the universal donor blood group. It can potentially be transfused to any patient regardless of their blood type. In emergency situation, this type of blood can be given to the patient.

Correct Option: C

Type O blood group is considered the universal donor blood group. It can potentially be transfused to any patient regardless of their blood type. In emergency situation, this type of blood can be given to the patient.

Polytene chromosomes were first reported by EG Balbiani in 1881. They are quite common in salivary glands of insects and are therefore popularly called salivary gland chromosomes. Polytene chromosomes also occur in other organs of insects antipodal cells (of embryo sac), endosperm cells and suspensor cell of embryo. The chromosomes can reach length of 200 µm and contain 1000 to 16000 times DNA as compared to the ordinary somatic chromosomes. The giant chromosomes are formed by somatic pairing between homologous chromosomes, and repeated replication (endomitosis) of their chromatids.

Correct Option: D

Polytene chromosomes were first reported by EG Balbiani in 1881. They are quite common in salivary glands of insects and are therefore popularly called salivary gland chromosomes. Polytene chromosomes also occur in other organs of insects antipodal cells (of embryo sac), endosperm cells and suspensor cell of embryo. The chromosomes can reach length of 200 µm and contain 1000 to 16000 times DNA as compared to the ordinary somatic chromosomes. The giant chromosomes are formed by somatic pairing between homologous chromosomes, and repeated replication (endomitosis) of their chromatids.

The mathematical expression to calculate allele frequency can be given as p + q = 1. Where p represents the frequency of dominant allele and q represents the frequency of recessive allele. The bionomial expression of Hardy Weinberg’s law to calculate genotype frequency is
p² + 2pq + q² = 1
where p² = homozygous dominant
2pq = heterozygous dominant
q² = homozygous recessive.
Frequency of heterozygous individuals = 2 × 0.6 × 0.4 = 0.48.

Correct Option: D

The mathematical expression to calculate allele frequency can be given as p + q = 1. Where p represents the frequency of dominant allele and q represents the frequency of recessive allele. The bionomial expression of Hardy Weinberg’s law to calculate genotype frequency is
p² + 2pq + q² = 1
where p² = homozygous dominant
2pq = heterozygous dominant
q² = homozygous recessive.
Frequency of heterozygous individuals = 2 × 0.6 × 0.4 = 0.48.