1. Where have we been?

2. PHOTOSYNTHESIS TYPE II
WRITE the BALANCED equation for photosynthesis
LABEL the inputs (reactants) and outputs (products)
EXPLAIN what will happen to each of the products and reactants

3. Cells and Energy Release
Cellular Respiration
Cells and Energy Release

4. MORE FUN WITH TIM & MOBY

5. Question… Why do we breathe? 4th grade answer: “so we don’t die”
7th grade answer: “to take in oxygen, and breathe out carbon dioxide”
10th grade answer: TO FUEL CELL RESPIRATION!

6. Basic ideas
Breaking down high energy, large molecules into lower energy, smaller molecules.
If this process stops, cells DIE!!!!
Requires oxygen to fully occur.
Three step process;
Step 1 occurs in the cytoplasm of the cell
Steps 2 & 3 occur in the mitochondria of the cell

7. Here’s where it Happens!
"MIGHTY
Mitochondria"

8. This is the equation!
C6H12O6 +6O2 -> 6CO2 + 6H2O + energy (ATP& heat)
How does this look familiar?
Where do the “ingredients” (reactants) come from?
What happens to each of the “leftovers” (products)

9. WHAT’S ATP GOT TO DO WITH IT?
Adenosine Triphosphate
Chemical energy source for the cell
Think of it as cellular “money”

10. Three Stages of Cellular Respiration
STEP 1: Glycolysis (“GLUCOSE SPLITTING”)
1st stage of ALL energy releasing pathways.
Occurs in cytoplasm
A couple of ATP “coins” made
If you’re fermenting, stop here!
STEP 2: Krebs Cycle (citric acid cycle)
Occurs in the mitochondria
A few more ATP “coins” made
STEP 3: Electron Transport Chain (phosphorylation)
Occurs in the mitochondria (membranes)
ATP JACKPOT!!!!!!!!!!!!!!

11. CELL RESPIRATION OVERVIEW
Convert glucose to ATP
Accomplished in 3 steps:
Glycolysisin cytoplasm
Krebs Cyclein mitochondria
Electron Transport Chainin mitochondria
Remember: this requires Oxygen

12. Glycolysis
Food must have been transported to cells via the bloodstream
digested food gets into the bloodstream by diffusing through the intestinal walls into the capillaries.
1st stage in energy release from food
Input = glucose,
Outputs = small amount of ATP and pyruvates
These outputs are the inputs for the next stage

13. Krebs Cycle Series of chemical reactions ATP (energy) released
CO2 (waste) released

14. Electron Transport Chain
Series of reactions
Releases LOTS more ATP

15. CASHING IN…
Total energy released from 1 GLUCOSE MOLECULE DURING CELL RESPIRATION:
38 ATP

16. CELL RESPIRATION OVERVIEW
Convert glucose to ATP
Accomplished in 3 steps:
Glycolysisin cytoplasm
Krebs Cyclein mitochondria
Electron Transport Chainin mitochondria
Remember: this requires Oxygen

17. UH, OH…PROBLEM 1.) What if you don’t have mitochondria?
2.) What if there isn’t much oxygen around?

18. FERMENTATION TO THE RESCUE!
2 KINDS:
Alcoholic
Lactic Acid
These are ANAEROBIC processes
Little to no oxygen required

19. BIG PICTURE: When are these used?
CELL RESPIRATION
Eukaryotes with mitochondria
Adequate oxygen
Ex.
Animals
Plants
PRODUCES LOTS OF ATP!
FERMENTATION
Prokaryotes (no mitochondria) AND/OR
Inadequate or no oxygen available
Ex.
Yeast
Bacteria
Overworked Human muscles (no, your brain is not a muscle!)
Produces very little ATP, but hey, some is better than none!

20. Where ARE we GOING?