Zoology - Principles of Inheritance and Variation Question with Solution | TestHub
In mice, black coat colour (allele) is dominant to brown coat colour (allele). The offspring of a cross between a black mouseand a brown mousewere allowed to interbreed. What percentage of the progeny would have black coats?
Options:
Answer:
Solution:
Monohybrid cross is defined as "a genetic mix between two individuals who have homozygous genotypes, or genotypes that have completely dominant or completely recessive alleles, which result in opposite phenotypes for a certain genetic trait". The phenotypic ratio and genotypic ratio of the F2 generation for a monohybrid cross comes toand.
Mendel derived the law of dominance which states that "when an organism is heterozygous for a trait (meaning it has two different alleles for that gene), the allele that is expressed is the dominant one."
For the given cross of black coat mice and brown coat mice as per Mendel's law of dominance-
Parent - BB (Black Coat colour) X bb (Brown coat colour)
F1 generation
| B | b |
| Bb(Black) X | Bb |
| B b | B b |
F2 generation
| B | b | |
| B | BB | Bb |
| b | Bb | bb |
Phenotype ratio - 3:1
Black Coat - BB and Bb - 75%
Brown coat - bb - 25%
