Question

Question 49 2 pts Enzymes work either by lowering the activation energy or increasing the free energy of a reaction. True False Question 50 2 pts Adding more substrate will always speed up an enzyme catalyzed reaction, but adding more enzyme will never speed up the reaction rate. True False

Answer 1

You have asked multiple questions here. As per Chegg Q&A Guidelines, I am answering only the first question.

A chemical reaction occurs when the reactants collide. The collisions allow them to interact and if the orientation and energy of these reactants are correct enough, a stable product is formed. An efficient way to increase the number of collisions and thereby the chances of the reactant molecules hitting at proper angles is by increasing the temperature of the reaction mixture.

However, inside a living cell, temperature rise can have devastating effects. Hence enzymes and catalysts play roles. Enzymes bind to reactants at specific sites called active sites. They then undergo conformational change which allows the reactant molecules to react easily. In terms of energy, they work by lowering the activation energy of the molecules. And thus, more reactions can occur in a given time span thereby speeding the process.