Question

Which one of the following cannot be explained on the basis of Mendel's Law of Dominance?
(a)Alleles do not show any blending and both the characters recover as such in the ${ F }_{ 2 }$ generation
(b)Factors occur in pairs
(c)Out of one pair of factors one is dominant, and the other is recessive.
(d)The discrete unit controlling a particular character is called a factor.

Answer 1

Hint: Mendel's law of dominance is the concept that when two alternative forms of a hereditary factor are brought into gametic fusion, one of them dominates, suppresses, or masks the effects of the other, and expresses itself in the offspring.

Complete step by step answer:
The expression of an allele in a pair of contrasting pairs of characters, in heterozygous organisms, is called the Law of Dominance. In this, the expressed factor is called dominant, and the suppressed one is called recessive. The dominant factor will be expressed in homozygous and heterozygous conditions. But recessive factors would be expressed only in the homozygous condition. The contrasting character in a pair not mixed or blended with one another.

So, the correct answer is ‘Alleles do not show any blending and both the characters recover as such as ${ F }_{ 2 }$ generation.

Additional information: -Mendel’s law of dominance states that when two alternative forms of a hereditary factor are brought to gametic fusion, one of them conceal the expression of another trait. instead of contributing to a phenotype, the dominant allele will be expressed exclusively.
-The recessive allele will remain suppressed but will be transmitted to offspring in the same manner in which the dominant allele is transmitted. The recessive trait will only be expressed by offspring when they are present in homozygous condition; these offspring will breed true when self-crossed.

Note:
-Dominance is the ability of an allele to express itself phenotypically both in the homozygous and heterozygous conditions. Recessiveness is the inability to manifest its phenotypic presence in the homozygous genotype.
-When a genetic trait is recessive, a person will require to inherit two copies of the gene for the trait to be expressed. Thus, both parents have to be the carriers of a recessive trait in order to express that trait in the offspring.
-Mendel formulated three postulates based on the results of his monohybrid cross. Mendel's laws of inheritance are; the law of dominance, the law of segregation, and the law of independent assortment.