Explain how enzyme function is like a lock and key.

The lock and key model states that the active site of an enzyme precisely fits a specific substrate. The induced fit model states that the active site of an enzyme will undergo a conformational change when binding a substrate, to improve the fit.

the cytokine-activated janus kinase (jak)-signal transducer and activator of transcription (stat) pathway has an important role in the control of immune responses. dysregulation of jak-stat signaling is associated with various immune disorders.