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Mitocôndria 
Morfologia e constituintes da mitocôndria 
Reprodução 
Função 
•Produção de energia para a célula; 
•Respiração celular. 
Envolvimento da mitocôndria nos processos de obtenção de energia 
•Glicólise (Glucose2piruvatos); 
•Oxidação do piruvato em acetil CoA (2 piruvato 2acetil CoA) 
•Beta-oxidação (ácido graxo  n acetil CoA); 
•Ciclo do ácido cítrico; 
•Fosforilação oxidativa. 
A organização geral de uma mitocôndria 
A organização geral de uma mitocôndria 
Figure 14-8. The general organization of a 
mitochondrion. In the liver, an estimated 67% of 
the total mitochondrial protein is located in the 
matrix, 21% is located in the inner membrane, 
6% in the outer membrane, and 6% in the 
intermembrane space. As indicated below, each 
of these four regions contains a special set of 
proteins that mediate distinct functions. (Courtesy 
of Daniel S. Friend.) 
http://www.sumanasinc.com/webcontent/
animations/content/organelles.html 
http://www.sumanasinc.com/webcontent/animations/content/organelles.html
Origem da mitocôndria 
Figure 1-35. The origin of mitochondria. An ancestral eucaryotic cell is thought to have engulfed the bacterial ancestor of mitochondria, initiating a symbiotic relationship. 
http://www.sumanasinc.com/webcontent/animations/content/organelles.html 
Bactéria aeróbia 
Célula eucariótica 
anaeróbia 
ancestral 
Genoma da mitocôndria de humanos 
Figure 14-58. The organization of the human mitochondrial genome. The genome contains 2 rRNA genes, 22 tRNA genes, and 
13 protein-coding sequences. The DNAs of many other animal mitochondrial genomes have also been completely sequenced. Most 
of these animal mitochondrial DNAs encode precisely the same genes as humans, with the gene order being identical for animals 
that range from mammals to fish. 
Síntese das proteínas da mitocôndria 
Figure 14-64 The origins of mitochondrial RNAs and proteins. The proteins encoded in the nucleus and imported from the cytosol have a major role in creating the genetic system of the 
mitochondrion, in addition to contributing most of the organelle's other proteins. Not indicated in this diagram are the additional nucleus-encoded proteins that regulate the expression of individual 
mitochondrial genes at posttranscriptional levels. The mitochondrion itself contributes only mRNAs, rRNAs, and tRNAs to its genetic system. 
Origem das proteínas e RNAs da mitocôndria 
http://www.ncbi.nlm.nih.gov/bookshelf/?book=mboc4&part=A4754&rendertype=def-item&id=A5688
http://www.ncbi.nlm.nih.gov/bookshelf/?book=mboc4&part=A4754&rendertype=def-item&id=A5568
http://www.ncbi.nlm.nih.gov/bookshelf/?book=mboc4&part=A4754&rendertype=def-item&id=A5055
http://www.ncbi.nlm.nih.gov/bookshelf/?book=mboc4&part=A4754&rendertype=def-item&id=A5582
http://www.ncbi.nlm.nih.gov/bookshelf/?book=mboc4&part=A4754&rendertype=def-item&id=A5688
http://www.ncbi.nlm.nih.gov/bookshelf/?book=mboc4&part=A4754&rendertype=def-item&id=A5568
http://www.ncbi.nlm.nih.gov/bookshelf/?book=mboc4&part=A4754&rendertype=def-item&id=A5688
http://www.ncbi.nlm.nih.gov/bookshelf/?book=mboc4&part=A4754&rendertype=def-item&id=A5163
http://www.ncbi.nlm.nih.gov/bookshelf/?book=mboc4&part=A4754&rendertype=def-item&id=A5215
http://www.ncbi.nlm.nih.gov/bookshelf/?book=mboc4&part=A4754&rendertype=def-item&id=A5496
http://www.ncbi.nlm.nih.gov/bookshelf/?book=mboc4&part=A4754&rendertype=def-item&id=A5767
http://www.ncbi.nlm.nih.gov/bookshelf/?book=mboc4&part=A4754&rendertype=def-item&id=A5902
Figure 14-54. Mitochondrial fission. These processes involve both outer and inner mitochondrial membranes. (A) During fusion and fission, 
both matrix and intermembrane space compartments are maintained. Different membrane fusion machines are thought to operate at the outer and 
inner membranes. Conceptually, the fission process resembles that of bacterial cell division (discussed in Chapter 18). The pathway shown has 
been postulated from static views such as that shown in (B). (B) An electron micrograph of a dividing mitochondrion in a liver cell. (B, courtesy 
of Daniel S. Friend.) 
Fissão ou divisão binária da mitocôndria 
http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=mboc4.chapter.3331
Gordura 
Proteína 
Piruvato Piruvato 
Glicerol 
+ 
Ácido graxo 
Ácido 
graxo 
Proteína aminoácidos 
glucose CICLO 
DE 
KREBS 
FOSFORILAÇÃO 
OXIDATIVA 
Acetil 
 CoA 
Carboidratos Carboidratos 
Citoplasma 
Mitocôndria 
Membrana Plasmática 
Envolvimento da mitocôndria na produção de energia 
G 
L 
I 
C 
Ó 
L 
I 
S 
E - 
O 
X 
I 
D 
A 
Ç 
À 
O 
ATP 
ATP 
ATP 
C6H12O6 
 
(glucose)
 
6 CO2 + 6 H2O + 
 
Energia 
na forma 
 de calor e luz 
Oxidação não biológica da glucose 
6 CO2 + 36 H2O + 30(32) ATP C6H12O6 + 6 O2 + 30(32) Pi + 30(32) ADP + 30 H
+ 
Oxidação Biológica aeróbia da glucose 
Energia 
na forma 
 de ATP 
(glucose) 
Enzimas 
Piruvato Piruvato glucose CICLO 
DE 
KREBS 
FOSFORILAÇÃO 
OXIDATIVA 
Acetil 
 CoA 
Carboidratos Carboidratos 
Citoplasma 
Mitocôndria 
Membrana Plasmática 
ATP 
G 
L 
I 
C 
Ó 
L 
I 
S 
E 
Degradação de carboidratos na célula para obtenção de 
energia 
ATP 
ATP 
Glicólise (Glucose  2 piruvatos) 
http://205.246.6.53/cooper/4e/animations0303.html 
http://205.246.6.53/cooper/4e/animations0303.html
Figure 2-71. An outline of glycolysis. Each of the 10 steps shown is catalyzed by a 
different enzyme. Note that step 4 cleaves a six-carbon sugar into two three-carbon 
sugars, so that the number of molecules at every stage after this doubles. As indicated, 
step 6 begins the energy generation phase of glycolysis, which causes the net synthesis 
of ATP and NADH molecules (see also Panel 2-8). 
 
 
Resumo da Glicólise 
 
(Glucose  2 piruvatos) 
http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=mboc4.box.293
http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=mboc4.box.293
http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=mboc4.box.293
http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=mboc4.box.293
http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=mboc4.box.293
Nicotinamida adenina dinucleotídeo (NAD+)  NADH 
Nicotinamida 
Adenina 
Piruvato Piruvato glucose CICLO 
DE 
KREBS 
FOSFORILAÇÃO 
OXIDATIVA 
Acetil 
 CoA 
Carboidratos Carboidratos 
Citoplasma 
Mitocôndria 
Membrana Plasmática 
ATP 
G 
L 
I 
C 
Ó 
L 
I 
S 
E 
Degradação de carboidratos na célula para obtenção de 
energia 
ATP 
ATP 
Conversão do piruvato à acetil-CoA 
Glicólise/ 
Ciclo de Krebs/ 
Fosforilação oxidativa 
Piruvato Piruvato glucose CICLO 
DE 
KREBS 
FOSFORILAÇÃO 
OXIDATIVA 
Acetil 
 CoA 
Carboidratos Carboidratos 
Citoplasma 
Mitocôndria 
Membrana Plasmática 
ATP 
G 
L 
I 
C 
Ó 
L 
I 
S 
E 
Degradação de carboidratos na célula para obtenção de 
energia 
ATP 
ATP 
Gordura 
Glicerol 
+ 
Ácido graxo 
Ácido 
graxo 
- 
O 
X 
I 
D 
A 
Ç 
À 
O 
Ciclo de Krebs 
http://205.246.6.53/cooper/4e/animations0304.html 
http://www.mcgrawhill.ca/school/applets/abbio/quiz/ch05/how_the_kre
bs_cycle_wor.swf 
http://205.246.6.53/cooper/4e/animations0304.html
http://www.mcgrawhill.ca/school/applets/abbio/quiz/ch05/how_the_krebs_cycle_wor.swf
Flavina adenina dinucleotídeo (FAD)  FADH2 
Piruvato Piruvato glucose CICLO 
DE 
KREBS 
FOSFORILAÇÃO 
OXIDATIVA 
Acetil 
 CoA 
Carboidratos Carboidratos 
Citoplasma 
Mitocôndria 
Membrana Plasmática 
ATP 
G 
L 
I 
C 
Ó 
L 
I 
S 
E 
Degradação de carboidratos na célula para obtenção de 
energia 
ATP 
ATP 
Gordura 
Glicerol 
+ 
Ácido graxo 
Ácido 
graxo 
- 
O 
X 
I 
D 
A 
Ç 
À 
O 
Cadeia Respiratória ou cadeia transportadora de elétrons na 
FOSFORILAÇÃO OXIDATIVA 
http://highered.mcgraw-
hill.com/olcweb/cgi/pluginpop.cgi?it=swf::535::535::/sites/dl/free/0072437316/120071/bio11.swf::Electron%20Transport%20System%20and%20ATP%20Synthe
sisElectron 
http://www.nature.com/nrg/journal/v2/n5/animation/nrg0501_342a_swf_MEDIA1.html 
NADH + H+ NAD+ 
FADH2
 
FADH + H+ 
ATP sintase 
http://highered.mcgraw-hill.com/olcweb/cgi/pluginpop.cgi?it=swf::535::535::/sites/dl/free/0072437316/120071/bio11.swf::Electron%20Transport%20System%20and%20ATP%20SynthesisElectronhttp://www.nature.com/nrg/journal/v2/n5/animation/nrg0501_342a_swf_MEDIA1.html
http://www.nature.com/nrg/journal/v2/n5/animation/nrg0501_342a_swf_MEDIA1.html
ATP sintase 
Figure 14-15. ATP synthase. (A) The enzyme is composed of a head portion, called the F1 ATPase, and a transmembrane H+ carrier, called F0. Both F1 and F0 are formed 
from multiple subunits, as indicated. A rotating stalk turns with a rotor formed by a ring of 10 to 14 c subunits in the membrane (red). The stator (green) is formed from 
transmembrane a subunits, tied to other subunits that create an elongated arm. This arm fixes the stator to a ring of 3α and 3β subunits that forms the head. (B) The three-
dimensional structure of the F1 ATPase, determined by x-ray crystallography. This part of the ATP synthase derives its name from its ability to carry out the reverse of the 
ATP synthesis reaction—namely, the hydrolysis of ATP to ADP and Pi, when detached from the transmembrane portion. (B, courtesy of John Walker, from J.P. Abrahams et 
al., Nature 370:621–628, 1994. © Macmillan Magazines Ltd.) 
Metabolismo 
aeróbio 
x 
Metabolismo 
anaeróbio da 
glucose 
Degradação de 
carboidratos na célula 
para obtenção de energia 
Integração da produção de NADH e FADH2 e da produção de 
ATP 
Figure 2-87. Glycolysis and the citric acid cycle provide the precursors needed to synthesize many important biological molecules. The amino acids, nucleotides, lipids, 
sugars, and other molecules—shown here as products—in turn serve as the precursors for the many macromolecules of the cell. Each black arrow in this diagram denotes a 
single enzyme-catalyzed reaction; the red arrows generally represent pathways with many steps that are required to produce the indicated products. 
Coenzima A 
-oxidação 
 
(Ácido graxo  acetil-CoA) 
http://www.brookscole.com/chemistry_d/templates/student_resources/shared_resour
ces/animations/carnitine/carnitine1.html 
http://library.med.utah.edu/NetBiochem/FattyAcids/9_3.html 
http://www.brookscole.com/chemistry_d/templates/student_resources/shared_resources/animations/carnitine/carnitine1.html
Produtos fornecidos a partir da oxidação de açúcares e de 
gorduras 
Gordura 
Proteína 
Piruvato Piruvato 
Glicerol 
+ 
Ácido graxo 
Ácido 
graxo 
Proteína aminoácidos 
glucose CICLO 
DE 
KREBS 
FOSFORILAÇÃO 
OXIDATIVA 
Acetil 
 CoA 
Carboidratos Carboidratos 
Citoplasma 
Mitocôndria 
Membrana Plasmática 
Envolvimento da mitocôndria na produção de energia 
G 
L 
I 
C 
Ó 
L 
I 
S 
E - 
O 
X 
I 
D 
A 
Ç 
À 
O 
ATP 
Etapas da -oxidação 
http://www.wiley.com/legacy/college/boyer/0470003790/animatio
ns/fatty_acid_metabolism/fatty_acid_metabolism.htm8 
http://www.brookscole.com/chemistry_d/templates/student_resources/shared_resour
ces/animations/carnitine/carnitine1.html 
http://library.med.utah.edu/NetBiochem/FattyAcids/9_3.html 
http://www.wiley.com/legacy/college/boyer/0470003790/animations/fatty_acid_metabolism/fatty_acid_metabolism.htm8
http://www.wiley.com/legacy/college/boyer/0470003790/animations/fatty_acid_metabolism/fatty_acid_metabolism.htm8
http://www.brookscole.com/chemistry_d/templates/student_resources/shared_resources/animations/carnitine/carnitine1.html