1. Ch 9 The Need for Energy

2. 9.1 How do cells use E?
Cell Processes – make new molecules, build membranes and organelles, maintain homeostasis (active transportation).
Body Processes – muscle contraction, digestion, brain control

3. 9.1 Where does your body get E?
You EAT!
Carbohydrate, Lipids, and Proteins ALL get broken down
HIGH E bonds in Carbs and Lipids
All break down and eventually make…
ATP (adinosine triphosphate) – quick E for the cell

4. 9.1 How does ATP work? E is stored in the BONDS.
Each bond in ATP has more and more E.
Break a bond and E is released.

5. 9.1 Why is ATP so useful?
RECHARGABLE: ADP is like a rechargeable battery that is low…you can recharge it by
putting another phosphate group on it.
This alleviates the need for a cell to store large quantities of ATP (no space)
As long as phosphates are available you can recharge.

6. 9.1 How do cells get the E from ATP.
Proteins have special sites for ATP to bind.
E is used
After the 3rd P breaks off
ADP is released

7. ATP

8. 9.3 What is Cellular Respiration?
The process of mitochondria (power station of the cell) to break down glucose (from food) to make ATP.
There are 3 stages:
Glycolysis
Citric Acid/ Krebs
Cycle
Electron Transport
Chain (ETC)

9. 9.3 What is Glycolysis? Anaerobic Location: Cytoplasm Uses: Glucose
Makes: a little ATP and Pyruvic Acid

10. What is the Citric Acid Cycle?
Location: Mitochondria
Uses: Pyruvic Acis
Makes: a little ATP and electrons and CO2

11. What is the e- Transport Chain
Aerobic
Location: Inner Mito. membrane
Uses: electrons from CAC
Makes: A LOT of ATP and water

12. What is fermentation? When NO oxygen is present….
Glycolysis still happens, but next step is FERMENTATION
Essentially makes enough E to run glycolysis
Lactic Acid Fermentation
Used by animal cells
Produces lactic acid and 2 ATP
Alcoholic Fermentation
Used by yeast and some bacteria
Produces CO2 and ethyl alcohol

13. What is photosynthesis?
sunlight
6 CO2 + 6 H2O C6H12O6 + 6 O2
Job = take sun’s E and convert it into into something storable, such as sugar/starch

14. Where do the reactions take place?

15. 9.2 What is Photosynthesis?
Creates food/energy
Base of food chain in plant material (producers)
Creates O to breathe
O is a byproduct
Eliminates CO2
CO2 is taken in

16. 9.2 Describe the reactions of photosytnesis
Light Dependent Rxn.
Uses light and water to create ATP and O2 (we breath this)
Light Independent Rxn. (Calvin Cycle)
Uses ATP and split water from LD to create sugars (usable E)
upload.wikimedia.org/wikipedia/commons/a/a3/S...

17. Products
Reactants
grapevine.net.au/~grunwald/une/KLAs/science/i...

18. Compare and Contrast Photosynthesis Food/Glucose made CO2 taken in
O2 given off
H20 broken down
Requires light
Occurs in cells with chlorophyll
Cellular Respiration