1. Enzymes

2. What exactly is saliva? 98% water 2% electrolytes, mucus, and ENZYMES
Salivary amylase: an enzyme that begins chemical digestions. It breaks down big molecules called starch down into simple sugars.
***This explains why saliva breaks down a cracker (lots of starch) but will have no effect on steak!

3. Key Point #1
Enzymes speed up chemical reactions that take place in cells

4. Review Point Chemical reactions REARRANGE reactants into products
Important chemical reactions we will talk about in bio:
Photosynthesis, cellular respiration, the breakdown of food

5. Review Point Reactant: what is USED in a chemical reaction
Product: what is MADE in a chemical reaction

6. Catalyst
A Catalyst is a substance that speeds up turning reactants into products. Enzymes are nature’s catalysts.

7. Why are enzymes so important?
Without enzymes, chemical reactions could take place so slowly that your body wouldn’t be able to maintain homeostasis.
Balanced inside
Crazy environmental conditions!

8. So how do enzymes speed up a chemical reaction?

9. Key Point #2
Enzymes provide a place where reactants can come together and use less energy for reaction.
Reactants!
React faster on the enzyme
The product is made!

10. Substrate: in a reaction that uses enzymes, reactants are called SUBSTRATE

11. Active site: The place on the enzymes where substrate comes together

12. Lock and Key
Enzymes are VERY specific. Each enzyme usually only catalyzes one reaction. Scientists say substrates fit active sites like a lock and key!

13. Key Point #3
Enzymes only work correctly in certain conditions. Enzyme activity can be controlled by: 1. Temperature 2. pH 3. Other molecules

14. Whiteboards

15. What is the main job of an enzyme?

16. Name that biological chemical reaction!

17. Name that biological chemical reaction

18. In an enzyme-catalyzed reaction…
The reactants of the chemical equation are called_______________

19. What is the place where the substrate binds to the enzyme called?

20. Substrate or Enzyme?
The “key”

21. Substrate or enzyme
The starch in your cracker

22. Substrate or enzyme?
The blue

23. Name 3 things that control enzyme activity

24. Hypothesis: Why does the reaction rate level off after a certain amount of substrate is present?