Question

Law of dominance-recessiveness is provided by
(a)Back cross
(b)Incomplete dominance
(c)Monohybrid cross
(d)Dihybrid cross

Answer 1

Two versions of each gene, known as alleles, are received by Individuals. In a relationship between two versions of a gene, one allele is dominant which is expressed and the other is recessive and the effect of this allele is masked.

Complete step-by-step answer:
The Law of dominance-recessiveness is provided by the monohybrid cross. A monohybrid cross is made between homozygous genotypes or genotypes that have completely dominant or completely recessive alleles. Mendel postulated the Law of dominance and Law of Segregation by using this cross. An example of a monohybrid cross is the breeding of a long-stemmed pea plant with a short-stemmed pea plant. A cross between the two creates heterozygous offspring. The cross-pollination of tall and dwarf plants resulted in tall plants as Mendel experimented, but when this generation was self-pollinated one out of four was short.
Additional Information: Back cross – is a crossing of a hybrid with one of its parents or an individual genetically similar to its parent. It is done to achieve offspring with a genetic identity that is closer to that of the parent. The backcross is useful in genetics for studying or isolating (separating) certain characteristics in a group of animals or plants. A backcross is often called a top cross in animals. The mating of average females to a superior male, then backcrossing the female offspring to the same or a similar sire is an example of the back cross.
Incomplete dominance – Appearance of new traits in the progeny other than parental traits is called incomplete dominance. In other words, when a dominant allele does not completely mask the effects of a recessive allele, and the organism's physical appearance shows a blending of both alleles. It is also known as semi-dominance or partial dominance. For example, when one parent with straight hair and one with curly hair has a child with wavy hair.
Dihybrid cross –cross is made between a homozygous dominant parent to another homozygous recessive parent based on two characters. Mendel postulated the Law of Independent assortment by using this cross.
So, the correct option is ‘Monohybrid cross’.

Note: Pollination is the process of transfer of pollen grains from the male of a flower to the female stigma. The pollination of a flower by pollen from the same flower or another flower on the same plant is known as self-pollination. Whereas the transfer of pollen from another plant to the flower of another plant is known as cross-pollination.