2) What is the non-protein part of the enzyme called: a) apoenzyme; b)coenzyme; c) holoenzyme; d) multienzyme; e)isoenzyme; 3) What model of interaction between enzyme and substrate was proposed by Fisher: a) "hands and gloves" b) "key and lock" (+) c) "boots and feet" d) "racks" e) "induced correspondence"?

2) The correct answer is b) coenzyme. The non-protein part of an enzyme is called a coenzyme. Coenzymes are organic molecules that bind to enzymes and assist in catalyzing a reaction. They are often derived from vitamins and are essential for the proper functioning of enzymes.<br /><br />3) The correct answer is b) "key and lock" $(+)$ model. The "key and lock" model of interaction between an enzyme and substrate was proposed by Emil Fischer. According to this model, the enzyme and substrate possess specific complementary geometric shapes that fit exactly into one another. This specific interaction allows the enzyme to catalyze the reaction efficiently.