1. Respiration
Chapter 7 p

2. ATP Reminders Main energy molecule
Energy stored in bonds between phosphate molecules
Energy comes from food we eat

3. The Importance of Electrons
Energy to make ATP from ADP comes from movement of electrons
Where do these electrons come from?
We breathe so that oxygen can be the final electron acceptor from this process

4. Redox Reactions Oxidation- loss of electrons
Ex:
Reduction- gain of electrons
Redox = Oxidation + Reduction
The process by which electrons are transferred from one molecule to another

5. Electron Carriers Help with ATP formation
Molecules that transfer electrons from one molecule to another
Ex: NAD+
NAD+ is the oxidized form
NADH is the reduced form

6. An Overview of the 3 Stages of Respiration
2 ATP

7. Where does each step occur?
Glycolysis
Krebs Cycle
Electron Transport Chain

8. Cellular Respiration Produces 36 ATP molecules
Aerobic- process that requires oxygen
Releases carbon dioxide
Uses electron carriers to transfer energy
Enzymes enable electron transfers

9. Glycolysis Occurs in cytosol Requires energy input: 2 ATP Makes 4 ATP
Begin with glucose (6C), end with 2 pyruvic acid molecules (3C) that go on to the Krebs cycle
NET GAIN =
TOTAL ATP =

10. Krebs Cycle Occurs in mitochondria
Begins with pyruvic acid from glycolysis
Cycle occurs 2 times for each molecule of glucose
Makes 2 ATP
Readies electron carriers for the electron transport chain
TOTAL ATP =

11. Electron Transport Chain
Occurs in mitochondria
Makes remaining ATP using energy from the electron carriers
TOTAL ATP =

13. What happens if no oxygen is present?
Fermentation- anaerobic process (no oxygen) occurring when energy harvesting ends with glycolysis
Way to recycle electron carriers since the energy is not used in the Krebs Cycle and Electron Transport Chain
Causes cramps in muscles during exercise
Yeast produce alcohol