The document provides an overview of several key metabolic pathways including glycolysis, gluconeogenesis, the pentose phosphate pathway, glycogenesis/glycogenolysis, fatty acid oxidation, the citric acid cycle, electron transport chain, and oxidative phosphorylation. It discusses the overall reactions, substrates and products, compartmentalization in the cell, and purpose of each pathway. The pathways are categorized as catabolic, anabolic, aerobic, or anaerobic. The document also provides learning objectives related to describing the function and details of the outlined pathways.

1. Info from ch 14. Know where metabolic pathways take place
Stages of Catabolism
Intro to Pathways
• Identify the functions
• Identify the overall starting materials and
products
• Compartmentation
• Aerobic or anaerobic
• Catabolic or Anabolic
Glycolysis
(Embden-Meyerhof-Parnas pathway)
• Glycolytic endpoints - depending on which cell and
conditions, glucose metabolism results in the production of
ethanol, lactate and CO2, H2O via pyruvate
• This is the predominant fate of glucose in mammalian
cells
• Limited potential energy w/o O2 . Captured as ATP
• Pathway is found in all cells of the body
• This is primarily a cytosolic pathway
• Net reaction:
Glucose + 2 ADP +2 Pi + 2 NAD+ <-> 2 Pyruvate + 2 ATP + 2
NADH

2. Glycolysis
Predominant fate of glucose in
mammalian cells;
ATP production under
anaerobic conditions.
Cytosolic
Pathway is found in all cells of
the body.
In red blood cells, this is the
ATP producing pathway since
they have no mitochondria.
• Gluconeogenesis - Generation of glucose
from noncarbohydrate precursors
– The principle noncarbohydrate precursors of glucose
are lactate, pyruvate, citric acid cycle intermediates
and most of the standard amino acids.
– Main function is to make glucose to release into
circulation to maintain proper blood glucose levels.
– Triggered by low blood glucose levels
–
• Overall reaction (example)
Glucose + 4 ADP + 2 GDP + 6 Pi + 2 NAD+ + 2 H+
Gluconeogenesis

3. Starts with pyruvate
Synthesis of glucose from
noncarbohydrate precursors.
Takes place in the liver and kidney
only.
The first reaction is mitochondrial
and the rest are cytosolic.
Stimulated when blood glucose
levels are low. This triggers
glucagon release which stimulates
this pathway.
Pentose Phosphate Pathway
6 NADPH + 6 H+ + 3 CO2 + 3 Ribulose 5 P.
NADPH is the biological reducing agent
required for biosynthetic processes.
Also required for the cells to deal with
oxidative stress.
• Cytosolic
• Many tissues (especially liver, mammary
gland, adipose tissue and adrenal cortex)
Glycogenesis (glycogen synthesis) and
glycogenolysis (glycogen breakdown)
• Glycogenesis

4. – Addition of glucose units to pre-existing
glycogen molecules, using UDP-glucose as
activated glucose donor
– Triggered by high blood glucose levels
Glycogenesis (glycogen synthesis) and
glycogenolysis (glycogen breakdown)
• Glycogenolysis
– Release of glucose as glucose-phosphate from
stored glycogen molecules
– Triggered by low blood glucose levels
Mitochondria – pathways that require O2
• Pyruvate Dehydrogenase complex
• Citric acid cycle
(TCA, tricarboxylic acid cycle)
• Electron transport coupled to oxidative
phosphorylation
• Overall aerobic catabolism
• Fatty acid beta oxidation
Pyruvate Dehydrogenase
• The aerobic utilization of pyruvate

5. produced in glycolysis.
• Overall of the five reactions
acetyl CoA + CO2 + NADH
O2 not directly involved, but required for
NADH to be re-oxidized in electron
transport coupled to oxidative
phosphorylation.
Fatty Acid Beta Oxiation
• Catabolic pathway in which fatty acids
are oxidatively degraded to yield acetyl-
CoA, NADH and FADH2
• Takes place in the mitochondrial matrix.
• Overall reaction for degradation of a 16 C
saturated fatty acyl CoA
• Palmitic
Citric Acid cycle (TCA)
• Takes place in mitochondria in the matrix
Oxidation of Acetyl CoA (another cross road metabolite) to
release CO2
and reduced coenzymes.
- Sources of acetyl CoA
- From pyruvate dehydrogenase comples (from glucose via
glycolysis)
• ß oxidation of fatty acids – releases acetyl CoA
• selected amino acids – deaminated to release acetyl CoA

6. • Utilizes biological oxidizing agents NAD+ and FAD,
producing NADH and
FADH2.
• An aerobic pathway because O2 is necessary to reoxidize
these reduced
coenzymes.
• Function is to oxidize products of stage 2 catabolism to
release carbons as
CO2 and produce ATP and reduced coenzymes which will result
in ATP
production in electron transport coupled to oxidative
phosphorylation
• Also has some biosynthetic purposes
Intermediates of pathway used as biosynthetic precursors.
Overall Reaction of one round of TCA:
3 NAD+ + FAD + GDP + Pi + acetyl-
3 NADH + FADH2 + GTP + CoA + 2 CO2
AGAIN – YOU DO NOT
NEED TO MEMORIZE ANY
OF THESE INDIVIDUAL
STEPS at this time.
Cyclic
- Oxaloacetate –
- only a small amount is
needed - catalytic

7. role
- Anapleurotic –
- “filling up” cycle can
be used as entry and
exit for production of
other essential
metabolites
Electron Transport Coupled to
Oxidative Phosphorylation
• Multiple steps used to reoxidize NADH
and FADH2 to NAD+ and FAD
• O2 is the final electron acceptor
(strongest oxidizing agent) of the chain.
• Free energy produced from a proton
gradient generated across the
mitochondrial inner membrane used to
drive the synthesis of ATP.
Morphology of Inner Mitochondrial
Membrane and Electron Transport and
Oxidative Phosphorylation
NADH
• Overall reaction of Electron Transport
–
• Overall reaction of Oxidative
Phosphorylation (synthesis of ATP coupled
to electron transport).

8. – ATP + H2O catalyzed by ATP
Synthase complex.
• Function(s): Regenerate oxidized forms of
redox coenzymes
• Produce majority of ATP from the
catabolism of our fuels under aerobic
conditions
• Overall reaction of Electron Transport
– NADH + ½
• Overall reaction of Oxidative Phosphorylation
(synthesis of ATP coupled to electron transport).
–
complex.
• Function(s): Regenerate oxidized forms of redox
coenzymes
• Produce majority of ATP from the catabolism of
our fuels under aerobic conditions.
• 2.5 ATP/NADH and 1.5 ATP/FADH2
ATP Yield from Catabolism of
Glucose
• How many ATP per glucose catabolized
under anaerobic conditions?
– Look at glycolysis. Net of 2 ATP

9. ATP Yield from Catabolism of
Glucose
• How many ATP per glucose catabolized
under aerobic conditions?
– Count all of the ATP (and GTP), NADH and FADH2
produced starting with glucose completely
catabolized to CO2 and H2O
– 2 ATP + 2 NADH from glycolysis (7 ATP)
– 2 NADH from PDH (5 ATP)
– 6 NADH from 2 rounds of TCA (15 ATP)
– 2 GTP from 2 rounds of TCA (2 ATP)
– 2 FADH2 from 2 rounds of TCA (3 ATP)
– Net of 32 ATP
Learning Goals. After reviewing
these notes you will be able to:
• Identify the pathways that are stage 1, 2
and 3 catabolism.
• Recognize whether a pathway is
catabolic or anabolic based on the
description.
• List examples of catabolic and anabolic
pathways.
• Discuss the major metabolic functions of
cytosol, mitochondria, smooth and rough
endoplasmic reticulum, golgi apparatus,

10. Learning Goals: you should be able to
state the function, give overall
reactions (major substrates and
products), compartmentation of the
following pathways:
• Glycolysis
• Gluconeogenesis
• Pentose phosphate pathway
• Glycogenesis
• Glycogenolysis
• Fatty acid oxidation
• Citric Acid cycle (TCA)
• Electron transport
• Oxidative phosphorylation
SPEECH OUTLINE
Specific Purpose: To
Central Idea: The thesis statement.
INTRODUCTION – Label the parts of your speech
“Introduction”, “Body” and “Conclusion”
I. (Attention Getter) – narrative, startling statement or statistic
that will get our attention.
II. (Reveal your topic) – Tell us the subject of your speech.
III. (Establish Credibility) – Share personal experience,
another’s experience you know about, or simply prove to us
why we should listen to you/trust that you’re a reliable source.
IV. (Relevancy Statement) – Why should we care? Why is this
relevant to us as an audience?
V. (Preview of Main Points) - Restate the central idea here. The
C.I. above isn’t usually said aloud.

11. (TRANSITION: Previews what’s to come, or summarizes what
you’ve already spoken about, or both. The first one should not
summarize. Neither should the last one.).
BODY (notice that the Roman Numerals start over).
I. (First Main Point – A Complete sentence) – Topic sentence.
A. (Subpoint-supports the main point) – A Complete sentence.
1. Further describes “A”.
2. Further describes “A”.
3. Further describes “A”. Ex.
B. (Subpoint-supports the main point) – A Complete sentence.
1. Further describes “B”..
2. Further describes “B”.
3. Further describes “B”.
C. (Subpoint-supports the main point) – A Complete sentence.
1. Further describes “C”.
2. Further describes “C”.
3. Further describes “C”.
(TRANSITION:
)
II. (Second Main Point–A Complete sentence) Repeat Pattern
of Main Point I.
A. (Subpoint-supports the main point)
1.
2.
3.

12. B. (Subpoint-supports the main point)
1.
2.
3.
C. (Subpoint-supports the main point)
1.
2.
3.
(TRANSITION:
)
III. (Third Main Point–A Complete sentence) Repeat Pattern of
Main Point II.
A. (Subpoint-supports the main point)
1.
2.
3.
B. (Subpoint-supports the main point)
1.
2.
3.
C. (Subpoint-supports the main point)
1.
2.
3.
(TRANSITION:
)
CONCLUSION (notice that the Roman Numerals start over).

13. I. (Summary of Main points)
II. (Memorable Close/Clincher--Tie this back to Intro)
References