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Phenotypic and genotypic ratios according to Mendel’s pattern of inheritance is
(a) Different
(b) Same
(c) Average
(d) None of the above

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Last updated date: 27th Jul 2024
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Answer
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Hint: According to the dominance relationships of the alleles involved, the genotypic ratios produce characteristic phenotypic ratios. An expected 3:1 phenotypic ratio among the phenotypes of "A" and "a."

Complete answer:
The genotype ratio is the gene collection that is responsible for a specific phenotype in our DNA. The physical expression, or features, of that trait, is the phenotype ratio. For instance, it is said that two species that have even the slightest variation in their genes have different genotypes. Tt and TT are two genotypes that are distinct. So the ratio is 1:1, but for them, the phenotypes are the same, i.e., tall. The genotypic and phenotypic ratios may also be distinct.
The phenotypic ratio refers to the proportional number of offspring exhibiting a specific characteristic or combination of characteristics. In this scenario, depending on the genotype, the phenotypic ratio will show how many of the offspring will be tall and how many will be small. 
The genotypic ratio shows the number of times that genes for certain traits are crossed, a feature of an organism can be seen in the offspring. 1:2:1 is the genotypic ratio for this cross. Each gene has 2 alleles or variants, one from each parent, in animals and plants.

Additional information: The law of incomplete dominance states that where none of a gene's variables are dominant, a mixture of dominant and recessive characteristics is the phenotype of the heterozygous dominant person. In Mirabilis jalapa, for example, flower color indicates incomplete dominance and the monohybrid cross between two pure varieties gives a phenotypic ratio of 1:2:1 in the generation of F2, which is 3:1 in dominant traits. The genes that functionally operate as allelic pairs are pseudoalleles, but they are structurally distinct genes, not allelic pairs. Multiple alleles mean that more than two alleles of a gene are present; for instance, the inheritance of the ABO blood group is regulated by three I gene alleles, namely IA, IB, and IO. The ratio of a cross of many alleles and pseudogenes depends on the relationship between their recessive-dominance. Complementary genes are non-allelic genes that have an independent influence, but when their dominant forms are present together, they create a new trait. The 9:7 phenotypic ratio is provided by a dihybrid cross of complementary genes.
So, the correct answer is ‘(a) Different’.

Note: Generally, the genotype remains constant from one setting to another, although there may be occasional random mutations that cause it to alter. However, when the same genotype is exposed to different conditions, a wide range of phenotypes can be formed.