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Question: For a given Penthybrid cross for AaBbCcDdEe how many possible different genotypes and phenotypes are...

For a given Penthybrid cross for AaBbCcDdEe how many possible different genotypes and phenotypes are obtained in F2 generation.

Explanation

Solution

As we know, Genotype means the genetic makeup of any organism. In other orders it refers to the number of genes or set of genes an organism has.
Example- human beings have 32 pairs of chromosomes. As they are diploid organisms.
Similarly, phenotype refers to the observable or visible external traits such as hair color, body color, height, eye color of an organism.
The genetic contribution is done by both genotype and phenotype.

Complete explanation:
As we know that the famous scientist Gregor Mendel discovered both genotype and phenotype during his experiment on a pea plant (Pisum sativum) in 1986. The pea plant belongs to the poaceous family.
Genotypes can only be determined by means of cross breeding or self-breeding. He conducted his experiment on a pea plant, during his experiment he crossed a tall and a dwarf pea plant and observed the ratio as 1:2:11:2:1. This ratio is called the genotype of that organism.
Humans have two alleles at each locus with one allele inherited from each parent.
Different types of crosses are there- monohybrid cross and dihybrid cross.
Monohybrid refers to crossing of a single variant of individual. No cross breeding has occurred.
Dihybrid refers to crossing of two individuals, here cross breeding is the only way to determine whether the crossing has taken place or not.
Phenotype is termed as the morphological characteristics of an organism which are visible or their physical characteristics.
Examples are certain types of diseases, height, eye color, voice.
As we discussed above about genotype and phenotype this pent hybrid cross is a self -cross.
In the self- cross AaBbCcDdEe there are 5 heterozygous genes present.
First, we will calculate the number of genotypes- In order to calculate the genotype in F2 generation the formula used is 3n.
Here, n denotes the number of genotypes.
So, the number of genotypes will be 35= 243 - {\text{ }}{3^5} = {\text{ }}243.
Similarly, the number of phenotypes will be 2n= 32 - {\text{ }}{2^n} = {\text{ }}32.

So, there will be 243 genotypes and 32 phenotypes in F2 generation.

Additional information:
Punnett square is a square diagram used to demonstrate the genotypes of a cross. It was discovered after Reginald C. Punnett.
This helps biologists to determine the probability of an offspring. The square is a combination of maternal alleles with paternal alleles.

Note:
The genotypes and phenotypes are termed under Punnett square board.
This signifies the correct explanation of how genotypes and phenotypes are obtained.
Mendel proposed the mendelian laws of characters where they made numerous discoveries.