Ask Question
24 April, 03:34

What are Mendel's two principles (laws) of inheritance? How can these principles be explained by the events of meiosis?

+4
Answers (1)
  1. 24 April, 03:51
    0
    Mendel's First Law - Monoibridism: Gregor Mendel established the basic laws on heredity by studying the pis Pisum sativum. He chose this species because it is easy to grow, has very striking and contrasting characteristics, produces large numbers of offspring and, moreover, its flowers are monoecious (bisexual) and reproduce predominantly by self-fertilization, thus possessing pure lineages. He thought that some factor was responsible for the characteristic of the seed. Therefore, he decided to cross pure plants using the male part of a plant with yellow seeds and the female part with those of green seeds. In generation F1, all peas had yellow seeds, being called by Mendel hybrids. After this crossing, Mendel self-fertilized one of these hybrid seeds and the result of the second generation was 75% yellow seeds and 25% green seeds. With this, Mendel concluded that the factor for yellow would be the dominant and the factor for recessive green. Mendel's first law was also known as the mono-hybridism law, as it applies to hybrid individuals with respect to only one trait. Mendel's Second Law - Diibridism: After performing several tests of monohybridism, Mendel decided to experiment, this time, with two types of characteristics. Mendel crossed the seeds of yellow and flat peas (dominant) with green and rough seeds (recessive). The F1 generation consisted only of smooth yellow seeds, but was expected as the seeds were pure and with dominant characteristics. In generation F2, the presence of four types of characteristics was observed: 9/16 plain yellow; 3/16 rough yellow; 3/16 plain green and 1/16 rough green. From this, Mendel concluded that color inheritance is independent of seed surface. It is also concluded that pure and yellow pure seeds have genotype VV (yellow) RR (smooth), that is, VVRR (dominant), while pure green and rough have genotype vvrr (recessive).

    There is a correspondence between Mendel's laws and meiosis. Note that during meiosis, homologous chromosomes align in metaphase and their separation occurs randomly, in two equally viable possibilities. The segregation independent of the homologues and, consequently, of the factors (genes) that they carry, results in the genotypes AB, ab, Ab and aB. This can be related to the mendel laws described above.
Know the Answer?
Not Sure About the Answer?
Find an answer to your question 👍 “What are Mendel's two principles (laws) of inheritance? How can these principles be explained by the events of meiosis? ...” in 📗 Biology if the answers seem to be not correct or there’s no answer. Try a smart search to find answers to similar questions.
Search for Other Answers