Question

The $lac$ operon concept was proposed by

• A. Watson and Crick in $1953$
• B. Jacob and Monod in $1961$
• C. Jacob and Monod in $1969$
• D. Watson and Crick in $1963$

Answer 1

The correct option is B Jacob and Monod in $1961$

The $lac$ operon
The $lac$ operon is an inducible operon that remains usually in a repressed condition and gets activated only when the substance to be metabolised (lactose) is present.
Jacob and Monod
Francois Jacob and Jacques Monod proposed the operon model in $1961$.
Final answer
(A) Jacob and Monod in $1961$