enzyme action (module 1)

Question 1

what is the role of enzymes?

Answer 1

• speed up rate of reactions by lowering activation energy
• without being used up (catalyst)

Question 2

what are enzyme substrate complexes?

Answer 2

• enzymes have specific tertiary structure so specific active site
• substrate complementary to site and binds to it
• forming ES complex

Question 3

what is the most accepted model and how does it work?

Answer 3

• induced fit model
• active site not fully complementary to substrate
• so changes shape to fit substrate
  -this put strain on bonds of substrate causing bonds to break apart and low activation energy
• active site goes back to original shape after products form

Question 4

what is the lock and key model?

Answer 4

• active site fixed shape
• so fully complementary to substrate
• substrate binds to enzyme
• active site doesn’t change shape