1. Cellular Respiration

2. What is Cellular Respiration?
When organisms capture the _______ stored in the chemical bonds of food molecules such as glucose and other sugars made in photosynthesis.
Cellular respiration builds a molecule called
ATP, which powers all work within cells.
energy
ATP
Glucose Fructose
Monosaccharides
Sucrose: A disaccharide

3. Why ATP?
Why do we transfer the energy in the chemical bonds of glucose into ATP?
ATP is small
ATP is stable – but not too stable
The bond between the 2nd and 3rd phosphates in ATP holds a lot of energy.

4. Aerobic Respiration Requires Oxygen
Many ATP molecules are made by the mitochondria from the glucose.

5. Label the parts of the mitochondrion
Intermembrane space

6. 3 Steps to Cellular Respiration Breaking the bonds of Glucose for ATP
Glycolysis:
Occurs in the cytoplasm
No O2 required
made
Krebs or Citric Acid Cycle:
Occurs in the matrix
CO2 gas is released here
made
Electron Transport Chain
Occurs in the folds of the inner membrane (crista)
Uses O2 and about and water is made.
ATP
ATP
ATP

7. Breaking the First Bond of Glucose: Glycolysis
“Glyco” “lysis” literally means “sugar” “splitting”

8. = +2 NADH NAD+ NAD+ NADH NADH
Anytime bonds break, energy is released. Energy carriers can capture some of that energy. The remainder is released as heat.
NADH
NAD+ P
NAD+
NADH P
NADH
= +2

9. When bonds break, ATP can be made from that energy
Just observe what happens next….
ATP
ADP P
These smaller sugar molecules made from glycolysis are called Pyruvate
ATP
ADP P
ATP
= +2

10. The Krebs Cycle takes place in the Matrix of the Mitochondrion, where more bonds are broken.
NAD+
NADH
Food for thought… what gas am I?
The CO2 that gets exhaled
NADH
NAD+

11. The Krebs Cycle takes place in the Matrix of the Mitochondrion, where more bonds are broken.
Citric Acid

12. The Krebs Cycle takes place in the Matrix of the Mitochondrion, where more bonds are broken.
NADH
NAD+

13. The Krebs Cycle takes place in the Matrix of the Mitochondrion, where more bonds are broken.
NADH
NAD+

14. The Krebs Cycle takes place in the Matrix of the Mitochondrion, where more bonds are broken.
ATP
ADP
NAD+
NADH P

15. The Krebs Cycle takes place in the Matrix of the Mitochondrion, where more bonds are broken.
FADH2
FADH

16. What is gained per glucose molecule during the Krebs Cycle?
Energy Carriers
NADH = +4
FADH2 = +1 +8
But there were two molecules of pyruvate that entered the Krebs Cycle…
How many would actually be produced in this case?
What kind of waste was made in the Krebs cycle? +2
ATP = +1 +2
6 CO2 gas!

17. What are the energy carriers NADH and FADH2 for?
They power the Electron Transport Chain that make a lot of ATP!
Inside the mitochondrion. Folds of the inner membrane known as cristae.
Many ATP molecules will be produced in these Electron Transport Chains
Where is the Electron Transport Chain?

18. During this process, oxygen gas is used, LOTS of ATP is made, and water is created.
NADH
ATP
ATP
6 O2
FADH2
ATP
FADH2
FADH2

19. Electron Transport Chain
NADH
NADH and FADH2
Electron Transport Chain
34 ATP
2 ATP
2 ATP

20. Cellular Respiration Equation:
C6H12O6 + 6O2  6CO2 + 6H2O + 36 ATP
(Glucose)
Light Reactions

21. Photosynthesis and Respiration
With a neighbor, fill in the steps in this cycle of Photosynthesis and Respiration.
We will check your answers when you are done!

22. Fermentation: Anaerobic Respiration
Glycolysis
Occurs when there is not enough oxygen to sustain an activity, so ATP cannot be made in the mitochondria.
Two basic types:
Lactic Acid Fermentation (in animals)
Alcohol Fermentation (in micro-organisms such as yeast)
Fermentation keeps glycolysis going, so at least 2 ATPs can still be made, until oxygen levels are restored.