In-class Group Activity
FOOD INTAKE
Students are placed into the following
groups. Each group will be responsible for
their ‘roles’ in the metabolic process.
Lipids (fats/oils) Take an intermediate to Glycolysis (lipids first must be
converted into the forth glycolysis intermediate to enter
into glycolysis)
 Take an Acetyl CoA to the Kreb cycle (lipids are also
converted into Acetyl CoA which enters into the first
reaction of the Krebs cycle)
Proteins- Break proteins down into amino acids first
which may be converted to…
 Pyruvic acid (which enters the preparatory step fight
before the Kreb cycle)
 Acetyl CoA (which enters into the first reaction of the
Krebs cycle)
 Intermediates in the Kreb cycle
Carbohydrates (glucose most important,
other carbohydrates are converted into
glucose or other glycolysis intermediates)
Glycolysis-10 reactions (if starting with glucose)
Glucose
A-H are intermediates in
glycolysis- through a series of
chemical reactions (each
requiring a different enzyme),
glucose is converted into
Molecule A. Molecule A is
converted into Molecule B, and
so on until 2 pyruvic acid
molecules are produced (which
then goes on to the Preparatory
Step before the Krebs cycle).
During the intermediate
reactions, other molecules are
also produced other than A-H.
See important products below.
A
Use 2 ATPs
B
C
D
D
E
E
F
F
G
G
H
H
Pyruvic acid
Pyruvic acid
Make 4 ATPs
You will need to take these important products to their appropriate place after they are produced.
Important products (from one molecule of glucose):
Pyruvic acid (2- take them to the Preparatory Step before the Krebs cycle)
ATP (make 4 but use 2, therefore net 2 for cellular anabolic needs -through substrate level
phosphorylation)
NADH + H+ (2, made when D turns into E- take them to the electron transport chain)
Note: In the reactions where NAD+ is reduced to NADH, another reactant in the reaction is being
oxidized (losing their H/e- to NAD+)
Preparatory Step – Between Pyruvic acid and the Krebs cycle
Pyruvic acid + NAD+
NADH
CO2
Acetyl Co A
You will need to take these important products to their appropriate place after they are produced.
Important products (from one molecule of glucose- therefore, 2 pyruvic acids go through the same
Preparatory Step):
Acetyl CoA (2- Take them to the Krebs cycle
NADH + H+ (2- Take them to the electron transport chain)
CO2 (2- diffuse out of the cell as a waste product)
Note: When NAD+ is reduced to NADH, another reactant in the reaction is being oxidized (losing their
H/e- to NAD+)
Krebs cycle
(2 Krebs cycles for every one glucose molecule, a series of 8 reactions if starting from glucose)
Acetyl CoA
A-G are intermediates in
glycolysis- through a series of
chemical reactions (each
requiring a different enzyme),
Acetyl CoA and oxaloacetic acid
react to produce into Molecule
A. Molecule A is converted into
Molecule B, and so on.
Oxaloacetic acid is the produce
of the 10th reaction and must
wait for more Acetlyl CoA to
continue the cycle.
+
Oxaloacetic acid
A (citric acid)
B
C
D
E
F
G
During the intermediate
reactions, other molecules are
also produced other than A-G.
See important products below.
You will need to take these important products to their appropriate place after they are produced.
Important products (from one molecule of glucose- therefore, 2 Krebs cycles occur for every one
NADH + H+ (6- 3 per cycle- Take them to the electron transport chain)
FADH2 (2- 1 per cycle- Take them to the electron transport chain)
CO2 (4- 2 per cycle- diffuse out of the cell as a waste product)
ATP (2- 1 per cycle through substrate level phosphorylation)
Note: In the reactions where NAD+ is reduced to NADH, another reactant in the reaction is being
oxidized (losing their H/e- to NAD+)
Electron Transport Chain and Chemisomosis
A series of redox reactions where one electron carrier is oxidized (loses an H/e-) and another electron
carrier is reduced (picks up the H/e-).
p+
A-D are intermediate electron
carriers - through a series of
redox reactions (each requiring a
different enzyme), electrons are
passed from one electron carrier
anoother. Protons are pumped
to the other side of the
membrane. When the protons
diffuse back across the
membrane throught ATP
synthase, energy is released.
ATP synthase uses this energy to
catalyze the reaction:
ADP + Phosphate and ATP is
produced.
NADH
e-
p+
A
p+
B
p+
C
D
e- + p+ = H
H
Added to
Oxygen
creates
H2O
Take your ATP to Anabolic cellular needs.
ADP + phosphate + energy= ATP
Anabolic cellular needs
Call for ATP!

Protein Synthesis (You need ATP and amino acids)

DNA Synthesis (You need ATP and nucleotides)

Lipid Synthesis (You need ATP and glycerol and fatty acids)

Carbohydrate Synthesis (You need ATP and monosaccharides)
WAIT! You ran out of oxygen to make ATP for your anabolic life processes, what now? FERMENTATION!
How many ATPs from one molecule of glucose during fermentation?
So… would you need more glucose or less to get the same amount of ATP when using fermentation?