Question

Repressible operon system is usually found in (i) pathways. The pathway’s end product serves as a (ii) to activate the repressor, turn off enzyme synthesis and prevent overproduction of the end product of the pathway. Genes for this operon are usually switched (iii) and the repressor is synthesized in an (iv) form.

• A. (i) anabolic (ii) Corepressor (iii) on (iv) inactive
• B. (i) anabolic (ii) inducer (iii) off (iv) active
• C. (i) catabolic (ii) inducer (iii) off (iv) active
• D. (i) catabolic (ii) corepressor (iii) on (iv) inactive

Answer 1

The correct option is A (i) anabolic (ii) Corepressor (iii) on (iv) inactive

Repressible operon system is usually found in anabolic pathways. The pathway’s end product serves as a corepressor to activate the repressor, turn off enzyme synthesis and prevent overproduction of the end product of the pathway. Genes for this operon are usually switched on and the repressor is synthesized in an inactive form.