Ch 7
Cellular Respiration
7.1
Glycolysis & Fermentation
MMMMmmm....
You eat lunch…
 Digest its macromolecules...into


How do you get the ENERGY out?
Cellular Respiration—
What is it?
 Breaking
down organic molecules
(from food!)
 & Making ATP
◦ For cell’s chem reactions
Opposite of Photosynthesis—
Flip the equation!!
Cell Resp:
6O2 + C6H12O6  6CO2 + 6H2O + ATP

you can’t “make” sunlight, so you
make
ATP instead!!
3 Main Processes
1.
Glycolysis
Oxygen
2.
Aerobic: Cell Respiration
NO
Oxygen
3.
Anaerobic: Fermentation
Aerobic Respiration:
in mitochondria!
Glucose
Glucose
Pyruvic
Glycolysis
Acid
Glycolysis:
In cell’s
cytoplasm
Acetyl
Krebs
CoA
cycle
Ethanol & CO2
(plants, yeast)
Fermentation
Or lactic Acid
(without oxygen)
(animals)
6C & 4C
Electron
molecules
transport
No ATP but it
does allow
Alcohol
for
moreor
lactic acid
glycolysis to
take place
Anaerobic Respiration:
In cell’s cytoplasm
1. Glycolysis
In the cytosol
 No Oxygen!
 Basics:

◦ break glucose,
◦ Make:
 pyruvic acid, 2 net ATP, & NADH (e- carrier)
Glycolysis
2. Aerobic Respiration
Only If Oxygen is available
 Break Pyruvic acid, lots of reactions
(another cycle), lots of ATP made
 More on this in 7.2! 

3. Anaerobic Respiration
Fermentation
Fermentation (Anaerobic Respiration)
•
Breakdown of Pyruvic Acid
• NO OXYGEN required
•
AFTER Glycolysis (bc need pyr. acid)
•
DOES NOT Make ATP
but it does make NAD so glycolysis
can still happen
•
Fermentation
Lactic Acid Fermentation



Muscle Cells (ouch! The
burn!!)
Pyruvic Acid  Lactic Acid
NAD also made, goes back
to do more glycolysis
Alcoholic Fermentation

Yeast, bacteria, plants
**ethanol that’s put in gas is from corn!



Pyruvic acid  Ethanol +
carbon dioxide
NAD also, for more
glycolysis
Other uses:
◦ Yogurt, bread, beer, wine...it’s
all made from fermentation!
What’s the
difference?
Similarities?
HW Review! p. 136 #1-3,7
7.2 Aerobic Respiration
2. Aerobic Respiration

C6H12O6 + 6 O2 → 6 H2O + 6 CO2 + 38 ATP
Must have oxygen
 Make LOTS of ATP
 within the mitochondria

Mitochondria...Draw It!
Inner & Outer Membranes
 Cristae
 Matrix

Structure of Mitochondrion
Aerobic Respiration

3 Main Steps:
1.
Link Reaction:
Pyr Acid into Mito. Matrix
 Acetyl CoA (loses a C as CO2;
NADH made...goes to ETC)
Pyruvic
Acid
NAD+
NADH + H+
C C
Acetyl-CoA
CoA
C C C
CO2
CoA
C
C C C C
C C C C C C
Citric Acid
Oxaloacetic
Acid
NAD+
NADH + H+
NADH + H+
C
CO2
NAD+
C C C C
Ketoglutaric C C C C C
Acid
NAD+
Malic
Acid
FADH2
FAD
Succinic
Acid
C C C C
NADH + H+
ADP
ATP
+P
CO2
C
Hans!
(Krebs) 
2. KREBS Cycle:
Acetyl CoA broken down;
make CO2, H+, ATP, NADH, FADH2 (another e- carrier)
in Mit Matrix
1 glucose made every 2 turns
2 NADH
8 NADH
2 FADH2
2
2
6C
4C
4C
4C
Pair-Share…
Summarize the Krebs Cycle
3. Electron Transport Chain
REVIEW--Up to this point:
◦ 4 ATP (2 from glycolysis, 2 from Krebs)
◦ 10 NADH (2 from glycolysis, 2 from link, 6
Go to E.T.C.,
34 ATP made from Krebs)
◦ 2 FADH2 (from Krebs)
3. Electron Transport Chain
ETC is lots of proteins in cristae folds
that pass e-s & energy, H+
 ATP Synthase (enzyme, at end of ETC )

◦ Pump H+ from space to matrix, makes ATP

OXYGEN: final e- acceptor, end of ETC
◦ Makes WATER!! (remember the equation?)

E- carriers: NADH and FADH2
◦ 10 NADH
◦ 2 FADH2
30 ATP
4 ATP
The E.T.C.
Electron Transport
Hydrogen Ion Movement
Channel
Intermembrane
Space
ATP synthase
Inner
Membrane
Matrix
ATP Production
Electron Transport Chain’s the Last Step!
(Thank goodness, right?! )
Energy Summary
p. 144 1-6,8
We’ll do the rest of this when I
return...do the Ch Review and
hopefully I’ll be back tomorrow!
p.146 1,5,7,9,11,12,16,18,20
p.139
p. 147

P.147
chloroplast
sunlight
Thylakoid
chlorophyll
WATER
CO2 from
atmosphere
oxygen
Energy-carrying molecules
transferred to lightindependent reactions
Light-indep.
Rxns (Calvin
Cycle)
6-C sugar
(glucose)
WHY do your cells need Oxygen?
• oxygen must accept
the final e• If not, it stops the
ETC!
Summary of Cell Respiration
• 1ST STEP?
• Glycolysis- converts glucose to pyruvic
acid, only makes a little ATP
• Aerobic– pyruvic acid  CO2 & H2O
– ONLY in presence of oxygen
– Creates A LOT of ATP
Comparing
Photosynthesis & Cell Resp.

graphic organizer
Chemical Equation
C6H12O6 + 602
6CO2 + 6H2O + ATP
Light reactions and
Calvin Cycle
Harvesting Chemical Energy
• Cell Respiration
– Process in which
cells make ATP by
breaking down
organic compounds
– This is done in both
heterotrophs and
autotrophs