Write short notes in 150 words:
Epistasis
Epistasis is a phenomenon in genetics where the expression of one gene (epistatic gene) masks or modifies the effect of another gene (hypostatic gene) at a different locus. It's a form of gene interaction where one gene's presence prevents the expression of another, even if the latter is functionally present. This differs from dominance, which involves alleles at the same locus.
Epistasis often leads to modified Mendelian phenotypic ratios (e.g., 9:3:4 or 9:7 instead of 9:3:3:1 in a dihybrid cross). For instance, in dog coat color, a gene for pigment production (E/e) is epistatic to a gene for pigment type (B/b, black/brown). If a dog is 'ee' (no pigment), it will be yellow regardless of its B/b genotype, as the 'ee' genotype masks the expression of the B/b gene. Epistasis reveals the complex interplay of multiple genes in determining a single phenotype, highlighting that traits are rarely controlled by isolated genes.
Answered By:
Harsh Raj
Harsh Raj is a successful government exam expert, having cleared multiple stages of SSC CGL, IBPS PO, CDS, RRB NTPC, and Delhi Police SI exams himself and mentored more than 5000 students through direct mentorship. His expertise is in creating well researched content, especially MCQs, which have been directly asked by relevant commissions in multiple exams.
Similar Questions
Write short notes in 150 words:
Nuclear pore complexWrite short notes in 150 words:
LysosomeWrite short notes in 150 words:
Synaptonemal complexWrite short notes in 150 words:
AmphidiploidyWhat are the different methods of DNA sequencing? Elaborate the shotgun sequencing method.
What is organic evolution? Discuss in detail the indirect evidences of organic evolution with suitable examples.
Elucidate the molecular basis of sex determination in plants. Explain the role of homomorphic and heteromorphic sex chromosomes.
What are the different gene transfer methods in plants? Give a brief account of direct gene transfer methods.
What are transgenic crops? Discuss the prospects and risks involved in their cultivation.
Define biodiversity. Explain the various ex situ and in situ methods of conserving biodiversity.
Important Questions from Miscellaneous
Write a note in 150 words
Mendelian and non-Mendelian traits.Write a note in 150 words
Theoretical significance of Purum kinship-system.Write a note in 150 words
Smell as a signal among non-human primates.Write a note in 150 words
Osteodontokeratik culture and its makers.Discuss the Miocene hominoid remains and their significance in evolution.
