Principles of Anatomy
and Physiology
Thirteenth Edition
Gerard J. Tortora • Bryan H. Derrickson
Chapter 25
Metabolism and Nutrition
Copyright © 2012 by John Wiley & Sons, Inc.
Heat
released
Catabolic reactions
transfer energy from
complex molecules to
ATP
Simple molecules such as
glucose, amino acids, glycerol,
and fatty acids
ATP
ADP +
P
Complex molecules such as
glycogen, proteins, and
triglycerides
Anabolic reactions
transfer energy from
ATP to complex
molecules
Heat
released
1 Glucose
1
2
GLYCOLYSIS
ATP
+
2 NADH + 2 H
2 Pyruvic acid
2
FORMATION
OF ACETYL
COENZYME A
2 CO2
4
2 NADH + 2 H+
2 Acetyl
coenzyme A
ELECTRON
TRANSPORT
CHAIN
32 or 34
3
KREBS
CYCLE
2
ATP
4
CO2
6
NADH + 6 H+
2
FADH2
Electrons
ATP
e–
e–
e–
6
O2
6
H2O
Glucose
ATP
GLYCOLYSIS
NADH + H+
Pyruvic acid
FORMATION
OF ACETYL
COENZYME A
CO2
NADH + H+
1 Glucose
Acetyl
coenzyme A
2 ATP
ATP
2 ADP + 2
CO2
KREBS
CYCLE
NADH + H+
FADH2
Dihydroxyacetone
phosphate
Glyceraldehyde
3-phosphate
2 NAD+
ELECTRON
TRANSPORT
CHAIN
e–
ATP
2
4 ADP + 4
NADH + 2 H+
4
e–
e–
Pyruvic acid
O2
H2O
(a) Cellular respiration
(b) Overview of glycolysis
ATP
Glucose (1 molecule)
ATP
1
ADP
Glucose 6-phosphate
Glucose 6-phosphate
2
Fructose 6-phosphate
Fructose 6-phosphate
Phosphofructokinase
ATP
3
ADP
Fructose 1,6-bisphosphate
Fructose 1,6-bisphosphate
4
Dihydroxyacetone
phosphate
5
Glyceraldehyde
3-phosphate
Dihydroxyacetone
phosphate
Glyceraldehyde
3-phosphate
5
2 NAD+ + 2
6
2
NADH
+ 2 H+
1,3-Bisphosphoglyceric acid
(2 molecules)
1,3-Bisphosphoglyceric acid
(2 molecules)
2 ADP
7
2
ATP
3-Phosphoglyceric acid
(2 molecules)
3-Phosphoglyceric acid
(2 molecules)
8
2-Phosphoglyceric acid
(2 molecules)
2-Phosphoglyceric acid
(2 molecules)
9
Phosphoenolpyruvic acid
(2 molecules)
Phosphoenolpyruvic acid
(2 molecules)
2 ADP
10
2
ATP
Pyruvic acid
(2 molecules)
1 Glucose
Glycolysis
In cytosol
2 Pyruvic acid
Aerobic pathway
Anaerobic
pathway
Mitochondrion
2 NADH
+ 2H+
2 NAD+
2 Lactic acid
Pyruvic
acid
Pyruvate
dehydrogenase
CO2
NAD+
NADH + H+
Mitochondrial
matrix
Acetyl
group
Coenzyme A
(CoA)
Acetyl
coenzyme A
(enters
Krebs
cycle)
Glucose
ATP
GLYCOLYSIS
NADH + H+
Pyruvic acid
FORMATION
OF ACETYL
COENZYME A
CO2
NADH + H+
Acetyl
coenzyme A
ATP
CO2
KREBS
CYCLE
NADH + H+
FADH2
ELECTRON
TRANSPORT
CHAIN
e–
ATP
e–
e–
O2
H2O
(a) Cellular respiration
Pyruvic acid
NADH + H+
CO2
To electron
transport
chain
Acetyl
coenzyme A
CoA
NADH + H+
Citric acid
To electron
transport chain
KREBS
CYCLE
FADH2
ATP
CO2
CO2
NADH + H+
NADH + H+
To electron
transport chain
(b) Overview of Krebs cycle
Pyruvic
acid
To electron
transport chain
Acetyl
coenzyme A
Oxaloacetic acid
1
To electron
transport chain
Citric acid
8
Malic acid
2
7
KREBS
CYCLE
Fumaric acid
3
Isocitric acid
6
Succinic acid
5
4
Alpha-ketoglutaric acid
Succinyl-CoA
To electron
transport chain
Outer membrane
Matrix
Inner membrane
H+
channel
High H+ concentration
between inner and
outer mitochondrial
membranes
2
H+
H+
Electron
transport chain
(includes proton
pumps)
Inner
mitochondrial
membrane
1
3
Energy from
NADH + H+
Low H+ concentration in
matrix of mitochondrion
ADP + P
ATP synthase
ATP
Space between outer and
inner mitochondrial
H+
membranes
H+ channel
H+
Cyt c
e–
Inner
mitochondrial
membrane
e–
e–
Q
e–
e–
Mitochondrial
matrix
NADH + H+
NAD+
H+
3
2H+ + 1/2 O2
ADP + P
H2O
1
NADH dehydrogenase
complex: FMN and five
Fe-S centers
2
H+
Cytochrome b–c1
complex: cyt b,–cyt c1,
and an Fe-S center
3
ATP synthase
Cytochrome oxidase
complex: cyt a, cyt a3,
and two Cu
ATP
Glucose
In cytosol
Glycolysis
ATP
Pyruvic acid
Mitochondrial
matrix
CO2
NAD+
NADH + H+
Acetyl coenzyme A
KREBS
CYCLE
CO2
NADH + H+
FADH2
Electron
transport
chain
O2
ETC
ATP
H2O
Mitochondrion
BLOOD GLUCOSE
Hepatocyte
(liver cell)
Glucose
ATP
Phosphatase
Hexokinase
ADP
Glucose 6-phosphate
Glucose 1-phosphate
Phosphorylase
Uridine diphosphate glucose
GLYCOGEN
Key:
Glycogenesis
(stimulated by insulin)
Glycogenolysis
(stimulated by glucagon and
epinephrine)
GLUCOSE
Glucose 6-phosphate
Glyceraldehyde
3-phosphate
LACTIC ACID
GLYCEROL
Pyruvic acid
CERTAIN
AMINO ACIDS
Key:
Gluconeogenesis (stimulated by cortisol
and glucagon)
Apo C-2
Nonpolar lipids:
Cholesterol ester
Triglyceride
Apo E
Amphipathic lipids:
Phospholipid
Cholesterol
Apo B100
GLUCOSE
Glyceraldehyde
3-phosphate
GLYCEROL
Pyruvic acid
FATTY ACIDS
TRIGLYCERIDES
CERTAIN
AMINO ACIDS
Acetyl
coenzyme A
Ketone breakdown
in most body cells
Ketogenesis
in liver cells
Key:
Lipolysis (stimulated by epinephrine,
norepinephrine, and cortisol)
Lipogenesis (stimulated by insulin)
KREBS
CYCLE
Ketone bodies:
Acetoacetic acid
Beta-hydroxybutyric acid
Acetone
Alanine
Cysteine
Glycine
Serine
Threonine
Phenylalanine
Pyruvic acid
Tyrosine
Leucine
Lysine
Tryptophan
Aspartic acid
Asparagine
Phenylalanine
Tyrosine
Acetoacetyl
CoA
Acetyl CoA
Oxaloacetic acid
Isoleucine
Leucine
Tryptophan
Citric acid
Malic acid
Isocitric acid
Fumaric acid
Alpha-ketoglutaric
acid
Succinic acid
Succinyl CoA
Isoleucine
Methionine
Valine
Glutamic
acid
Arginine
Histidine
Glutamine
Proline
Glycogen (liver
and muscle cells)
Glucose
(in blood)
2
Certain
amino acids
1
Glucose 6-phosphate
3
Ribose 5-phosphate
and NADPH
4
GLYCOLYSIS
(cytosol)
DNA and RNA
ATP
5
7
6
Electrons
KREBS
CYCLE
(mitochondria)
Certain
amino acids
Lactic acid
Alanine
(amino acid)
Alpha-ketoglutaric
acid
e–
ATP
e–
Citric
acid
Oxaloacetic
acid
e–
O2
Pyruvic acid
H2O
9
8
Acetyl
coenzyme A
Triglycerides and Phospholipids
Fatty acids
Cholesterol
10
Certain amino
acids
Ketone
bodies
ELECTRON
TRANSPORT
CHAIN
(mitochondria)
SKELETAL
MUSCLE
Blood
Storage
MOST TISSUES
GLUCOSE
Oxidation
GLUCOSE
1
CO2 + H2O + ATP
4
Glygogen
Proteins
GASTROINTESTINAL
TRACY
8
AMINO ACIDS GLUCOSE
TRIGLYCERIDES
(in chylomicrons)
HEPATOCYTES IN LIVER
7
Glucose
6
2
Glyceraldehyde
Fatty acids 3-phosphate
Glycogen
Keto acids
Proteins
CO2 + H2O + ATP
Triglycerides
3
VLDLs
Triglycerides
ADIPOSE TISSUE
4
5
Glucose
Triglycerides
Fatty Glyceraldehyde
acids 3-phosphate
Triglycerides
ADIPOSE TISSUE
SKELETAL MUSCLE TISSUE
Triglycerides
HEART
2
Glycerol
Fatty acids
Muscle proteins
Fasting or
starvation
4
Amino acids
5
Fatty acids
ATP
9
Glucose
6-phosphate
Glycerol
Amino acids
Fatty acids
8
ATP
Liver glycogen
4
Muscle glycogen
ATP
7
1
Keto acids
Lactic acid
Ketone bodies
3
6
Lactic acid
ATP
8
Ketone bodies
ATP
OTHER TISSUES
4
Amino acids
Pyruvic acid
ATP
ATP
Glucose
ATP
+ O2
(aerobic)
5
Fatty acids
– O2
(anaerobic)
Lactic
acid
Fatty acids
NERVOUS
TISSUE
5
Ketone bodies
Glucose Ketone
bodies
Starvation
8
ATP
ATP
Proteins
ATP
8
ATP
Some stimulus
disrupts
homeostasis by
Decreasing
Body temperature
Receptors
Thermoreceptors in
skin and hypothalamus
Nerve
impulses
Input
Control centers
Preoptic area,
heatpromoting center,
and neurosecretory cells
in hypothalamus and
thyrotropes in anterior
pituitary gland
Nerve impulses
Output
and TSH
Return to homeostasis
when response brings
body temperature
back to normal
Effectors
Vasoconstriction
decreases heat
loss through skin
Adrenal
medulla
releases
hormones that
increase
cellular
metabolism
Skeletal
muscles
contract in
repetitive cycle
called
shivering
Increase in body temperature
Thyroid gland
releases thyroid
hormones,
which increase
metabolic rate
VEGETABLES
FRUITS
OILS
GRAINS
MILK
MEAT
&
BEANS