2. CELL ENERGY Chapter 4 Section 2

3. Cells need energy …  To live  To grow  To reproduce

4. The 4 Important Molecules:  H 2 O…  CO 2…  O 2…  C 6 H 12 O 6 …  Water  Carbon dioxide  Oxygen  Glucose

5. PHOTOSYNTHESIS  Process by which plants capture light energy from the sun and convert it into sugar  Happens in the chloroplasts within plant cells Song !

7. Photosynthesis means…

8. Terms to remember:  Reactant- any substance that undergoes a chemical change in a given reaction.  Product-a substance obtained from another substance through a chemical change.

9. Equation for Photosynthesis:  6CO 2 + 6H 2 O + light energy   C 6 H 12 O 6 + 6O 2 Yields reactants products

12. This takes place in the…

13. Pigment inside the chloroplasts that absorb the sun’s energy:

14. Leaves are a plant’s organs for collecting light! Leaves come in many shapes and sizes!

15.  ___________+__________ Reactants: Products: yields

16. Where do plants get the reactants?

17. CO 2 enters the leaves through … which are tiny openings in the underside of a leaf (Oxygen exits through these openings too !)

18. The opening is here These are called guard cells Watch animation !

19. Stomata on a cactus leaf:

21. 3 main things plants do with glucose:  Use it for energy  Build starch (store it)  or Build cellulose –(for cell walls) RapRap !

23. A way to get needed ATP !

24. And need to get ATP ?

25. Cellular Respiration  The process of producing ATP in the cell from oxygen and glucose;  Releases carbon dioxide and water  Occurs in the mitochondria:  Cellular respiration is not the same thing as “breathing”

26. Equation for Respiration:  C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + ( ATP  HEAT is also released (helps keep your body temperature constant) Happens in the mitochondria reactantsproducts

27. Plants and animals…  Both use cellular respiration to obtain energy

29. ____________+___________ __________+___________ Reactants:Products: CELLULAR RESPIRATION + _________

30. And need to get ATP ?

31. Fermentation  The breakdown of sugars to make ATP (in the absence of oxygen)  Yeast cells undergo fermentation in making bread, beer, and wine.

32. Fermentation in muscle cells: When your muscles are tired and can’t get enough oxygen, the cells use the process of fermentation to make ATP and produce LACTIC ACID as a by-product. This makes your muscles ache.

33. Lactic Acids in Foods: Lactic acid in foods: Lactic acid is primarily found in sour milk products, such as: koumiss, leban, yogurt, kefir and some cottage cheesesmilk koumissyogurtkefircottage cheeses