Question

 

Explain how Darwinian evolution relates to the creation of alleles in a population of sexually-reproducing organisms?

 

 Give 2 mechanisms of how gene expression patterns are controlled?

Answer 1

Darwin theory explains the evolutionary concepts of seggregating the different genes in the individual. The co existence of the genes from the both the parents in sexually reproducing animals, the genes in the pool which expresses dominance is called dominant allele. The natural selection theory perfectly explains about the inheritance characterstic feature of alleles.

To controll the gene expression there is different phenomenon in prokaryotes and Eukaryotes.

In prokaryotes the two mechanisms which regulates the gene expression is LAC OPERON and TRP OPERON mechanims. The lactose is inducer and regulates the transcription rate, presence of lactose it self indicates needs the enzymes for the cleaving, so i binds to the regulatory protein and prevent frmo blocking of repressor protein to bind at operator sequence.

In case of TRYPTOPHAN Operon the case is different attenuation occurs, the presence of Tryptophan induces and stops the transcription rate,

In Eukaryotes the transcription initiatiation itself regulates, because for the expression of gene transcription and protein synthesis are key steps to follow.