1. CELLULAR RESPIRATION (An Introduction)
3.7 & & 8.1

2. Organisms use energy from ATP for all its activities
Breathing
Heart pumping
Maintaining body temperature
Thinking, dreaming

3. AUTOTROPHS
- all organisms require energy and have evolved to take free energy from the environment and convert it into usable forms
AUTOTROPHS: create their own food (which will later be broken down into usable energy)

4. AUTOTROPHS 1) Photoautotrophs:
Organisms that use photosynthesis to convert light energy into chemical potential energy in glucose
ex: green plants

5. Autotrophs.... 2) Chemoautotrophs:
Sulfolobus acidocaldarius
2) Chemoautotrophs:
microorganisms the are able to extract energy from inorganic compounds containing elements such as sulphur and iron
usually found in extreme environments such as volcanoes, sulfur springs
Ex: archaebacteria

6. HETEROTROPHS…
HETEROTROPHS: must consume autotrophs or other heterotrophs in order to gain energy.
Includes the majority of organisms (including all animals and fungi, many protists and bacteria)
- all organisms except chemoautotrophs use glucose (C6H12O6) as their primary source of energy.

7. Cellular Respiration
The process of extracting energy from nutrient molecules (ie glucose) and storing it into a usable form (ATP) so the cell can use it for energy-requiring activities.
Overall equation:
C6H12O O2 + 36ADP + 36Pi CO2 + 6 H2O + 36 ATP
oxidized reduced ENERGY

8. Cellular Respiration It is a combustion reaction!
(Glucose is reacted with Oxygen to produce energy)
In cellular respiration, several enzymes are used to lower the overall activation energy of the reaction and to maximize the amount of energy that can be produced

10. Gummy Bear
An oxidation (combustion) reaction. If our bodies relied upon heat and not enzymes to harvest energy from glucose!

11. Redox Reactions Reduction – oxidation reactions.
Reduction – when a compound gains an electron
Oxidation – when a compound loses an electron.

12. Helpful Memory Tricks:
“LEO the lion goes GER”
LEO: Loss of electrons is oxidation
GER: Gain of electrons is reduction
“OIL RIG”
OIL: oxidation is loss (of electrons)
RIG: reduction is gain (of electrons)

14. Example Na + Cl  NaCl Na Cl  [Na]+ [ Cl ]- OXIDIZED REDUCED
(Oxidizing Agent – allows Na to be oxidized)
(Reducing Agent – allows Cl to be reduced)

15. Redox Reactions
During redox reactions, electrons are passed from molecule to molecule in sequence (moves to more electronegative compounds)
As it is passed along, the molecules will be reduced and oxidized.
This movement of electrons is a form of energy (electrochemical energy) and can be converted into other forms….

16. Redox Reactions B C- D A- C B- D- A
Increasing electronegativity

17. Adenosine triphosphate

18. ATP
Nitrogen base (Adenine)
3 phosphate groups
Ribose sugar

19. Diphosphate +phosphate
ATP releases energy
Phosphate bonds are high energy bonds
Diphosphate +phosphate
Breaking the bonds releases the energy
ATP ADP + Pi + Energy

20. ATP is Recycled
ATP is an energy-containing molecule used to supply the cell with energy. The energy to produce ATP comes from glucose or other high energy compounds
ATP is continuously produced and consumed
Phosphorylation = attaching a phosphate group to a molecule to make the molecule more reactive

21. Overall 3 goals of cellular respiration:
Breaks bonds between 6 carbon atoms (of C6H12O6 ) to make 6 CO2
Moves H atom electrons from C6H12O6 to O2 to make 6 H2O
Trap as much free energy as possible in ATP

22. Energy Transfer
Aerobic Respiration occurs via 2 different energy transfer mechanisms
Substrate-Level Phosphorylation
Oxidative Phosphorylation

23. A) SUBSTRATE LEVEL PHOSPHORYLATION
ATP is produced directly in an enzyme catalyzed reaction.
The enzyme transfers a phosphate group from a substrate molecule (ie PEP) to ADP to make ATP

24. Page 95 figure 2
Pg 94 Figure 2: the enzyme allows Pi group to transfer to ADP to make ATP

25. B) OXDATIVE PHOSPHORYLATION
ATP is formed indirectly
It is more complex than substrate-level phosphorylation and makes much more ATP
ATP is formed via a series of redox reactions where O2 is the final electron acceptor
The energy released during the redox reactions is used to generate ATP.

26. A dehydrogenase enzyme catalyzes the reactions; NAD+  NADH
Uses NAD+ (nicotinamide adenine dinucleotide) and FAD (flavin adenine dinucleotide) which are co-enzymes that will move electrons and energy from one molecule to another
A dehydrogenase enzyme catalyzes the reactions;
NAD+  NADH
The enzyme removes 2 H atoms (so 2 protons, and 2 electrons) from glucose
Delivers 1 H+ & 2 é to NAD+ to make NADH (the other H+ is dissolved in the surrounding solution)
FAD  FADH2
FAD is also reduced by 2 hydrogen (2 H+ & 2 é)
They both eventually transfer their free energy to ATP

27. oxidized form reduced form FAD + (2H + + 2é) FADH2
NAD+ + H + + 2é NADH
oxidized form reduced form
FAD + (2H + + 2é) FADH2
Stores energy- most of which will be transferred to ATP

28. 4 STAGES
1)GLYCOLYSIS – in cytoplasm 2) PYRUVATE OXIDATION – in mitochondrial matrix 3) KREBS CYCLE – in mitochondrial matrix 4) ELECTRON TRANSPORT CHAIN AND CHEMIOSMOSIS – inner mitochondrial membrane
Aerobic respiration

30. Mitochondria OUTER MITOCHONDRIAL MEMBRANE
- Similar function to cell membrane
INNER MITOCHONDRIAL MEMBRANE
Assists with cellular respiration
embedded with many proteins and enzymes
MATRIX
- Inner, fluid filled section
INTERMEMBRANE SPACE
- Fluid filled space between the inner and outer membranes
CRISTAE
- Folds of the inner membrane

32. Stage 1: GLYCOLYSIS
A 10 step process that occurs in the cytoplasm of the cell
Does not require oxygen (anaerobic)
During glycolysis, glucose is broken down into 2 molecules of pyruvate
2 ATP molecules are used to phosphorylate and activate compounds
4 ATP are produced (Net 2ATP) and 2 NADH produced

35. Summary of Glycolysis 2 ATP 2 ADP
Glucose (C6)
P- C6-P
(fructose 1, 6 biphosphate)
2 C3-P
(G3P-glyceraldehyde 3-phosphate)
2 P-C3-P
(BPG 1,3-biphosphoglycerate)
2 pyruvate (C3)
2 ATP
2 ADP
Glucose is converted into 2 pyruvate molecules
Free energy is captured in ATP and NADH
2 NAD+
2 NADH
2 Pi
2 ADP
2 ATP

36. 2 net ATP produced (4 produced but 2 used in the process) – which can be used by the cell immediately
2 NADH produced – which can be processed to produced more ATP
The 2 pyruvate molecules will now go to the mitochondrial matrix for aerobic respiration
If oxygen is not available, fermentation will occur instead.