Question
Question: Short/long answer type questions. Discuss Mendel Laws of inheritance. Which one of these laws do y...
Short/long answer type questions.
Discuss Mendel Laws of inheritance. Which one of these laws do you consider the most important and why?
Solution
Number of characters is present in each organism like height, skin color, hair color, eye color, etc. Alleles represent the different characters of organisms, homozygous alleles represent the same trait of character whereas heterozygous alleles represent the same character with different traits.
Complete answer:
After the pea experiment, Mendel proposed the basic principle of inheritance which is also called a Mendel law of inheritance or Mendelism. In this Mendel had given two laws, the law of dominance and the law of segregation.
The Law of the principle of Dominance states that in the case of heterozygous alleles only the dominant allele expresses itself while the recessive allele is unable to show its effect. This law is useful for the expression of only one parental character.
The Law of segregation states that the different characters present on alleles do not mix up and remain distinct. Segregation of characters takes place at the time of gamete formation in animals and at the time of spore formation in the plant.
From both of these laws, the law of segregation is more important because it expresses both the alleles in the case of hybrid. Here the case of dominant and recessive doesn't exist. In the case of hybrid, two different parents contribute two different alleles and the offspring that are produced have both the traits.
Additional Information: Incomplete dominance and codominance follow the law of segregation. In the case of incomplete dominance dominant trait and recessive trait express itself individually whereas in the case of hybrid both characters mixed up and a new character form. Here the law of dominance doesn't work.
In the case of codominance, the dominant and recessive character doesn't exist because both alleles express themselves simultaneously. Blood group and sickle cell anemia follow codominance.
Note: Multiple alleles and pleiotropic genes also don’t follow the law of dominance. Multiple alleles showed by eye color of drosophila, and coat pigment in rabbits was more than two forms of genes present. In pleiotropy, the same gene controls the expression of a number of characters.