IGNOU BBCCT 123 2026 - Explain the principles of positive and negative regulation of gene exp

Question

Explain the principles of positive and negative regulation of gene expression with reference to operons.

10 Feb 2026

Answer :

Word Count : 260

Gene expression in prokaryotes is tightly regulated to ensure that proteins are synthesized only when needed, conserving cellular resources. The operon model, first proposed by Jacob and Monod, illustrates how groups of genes can be coordinately controlled by regulatory elements. An operon typically consists of structural genes, a promoter, an operator, and regulatory genes that encode repressors or activators. Positive regulation involves the activation of gene expression by a regulatory protein known as

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