Enzymes

1. Enzymes

2. Enzymes • Each chemical reaction that occurs in a living thing is controlled by an enzyme • Ends in –ase (lactase, amylase) • Enzymes speed up chemical reactions that take place in cells • Catalyst is something that speeds up or slows down chemical reaction • Reduces the amount of energy need to start that reaction

3. Vocabulary • Substrate-reactants of an enzyme-catalyzed reaction • Catalyst-substance that speeds up the rate of a chemical reaction • Activation energy –energy needed to get reaction started • Product-substance you end up with at the end of a chemical reaction

4. Effects of Enzymes

5. What Happens??? • Catalysts are not permanently changed or used up by the reaction

6. Locks and Keys • Just like a door with a lock and key, enzymes work the same way • Enzymes complete very specific jobs and do nothing else • Enzymes are very specific “locks” and the compounds they work with are the special “keys”

7. 4 steps of how an enzyme works 1. An enzyme and substrate are in the same area. The substrate is the biological molecule that the enzyme will work on.

8. 2. The enzyme grabs onto the substrate with a special area called the active site. The active site is a specially shaped area of the enzyme that fits around the substrate. The active site is the keyhole of the lock.

9. 3. A process called catalysis happens. Catalysis is when the substrate is changed (broken down or combined with another molecule to make something new)

10. 4. The enzyme lets go. When the enzyme lets go, it returns to normal, ready to do another reaction. Substrate is no longer the same. The substrate is now called the product.

11. Can You Stop Them? • Good Question! If an enzyme just kept going and going and converted every molecule in the world ….ack….it would never stop….like a monster! We need to control enzymes HOW?????

12. Affects Enzyme Activity • Temperature proteins change shape as temps change -enzyme’s activity depends on it’s shape it, temp changes can mess up the process and enzymes won’t work

13. 2. pH Levels acidity also changes the shapes of proteins 3. Activators make enzymes work harder and faster 4. Inhibitors opposite of activators, inhibitors either slow down or stop enzyme activity ex: snake venom or nerve gas