Biochemistry Fischer’s lock and key theory’ postulates that: A Active site in enzyme exists in proper conformation to the substrate molecule even in absence of substrate B Active site during binding to substrate under goes conformational changes to fit C There is absolute specificity in reaction between enzyme and substrate D Enzymes have catalytic power and accelerate reaction by reducing energy of activation 💡 Explanation Fischer's lock and key theory' postulates that: ✓ Correct Answer: A. Active site in enzyme exists in proper conformation to the substrate molecule even in absence of substrate