Download - Respiración celular
Bio 1112009
Transformación de energía a partir de glucosa
Aeróbico – requiere O2
Reacción catabólica, donde se libera energía en forma de ATP
Reacciones REDOX
Reacción general del rompimiento de glucosa:
C6H12O6 + 6O2 6CO2 + 6H2O + ATP
Figure 8-1 Biology: Life on Earth 8/e ©2008 Pearson Prentice Hall, Inc.
34 or 36ATP
in mitochondria–oxygen required
in cytosol–no oxygen required
glycolysis
glucose
fermentationpyruvate
2 ATP
cellular respiration
O2
if no O2 availableethanol + CO2
orlactic acid
CO2
H2O
Glycolysis Formation of acetyl coenzyme A
Citric acid cycle
Electron transport and chemiosmosis
Glucose
Pyruvate
2 ATP 2 ATP 2 ATP
Acetyl coenzyme A
Citric acid cycle
Electron transport and chemiosmosis
1 2 3 4
Figure 8-6 Biology: Life on Earth 8/e ©2008 Pearson Prentice Hall, Inc.
cristae
mitochondrion
innermembrane
outermembrane
intermembranespace
matrix
Glycolysis Formation of acetyl coenzyme A
Citric acid cycle
Electron transport and chemiosmosis
Glucose
Pyruvate
2 ATP 2 ATP 2 ATP
Glucólisis Ocurre en el citoplasma En ausencia de oxígeno La glucosa se rompe y se obtiene dos piruvatos Se produce dos ATP por cada molécula de glucosa
Glucose
Glucose-6-phosphate
Fructose-6-phosphate
ATP ATP
ADPADP
Hexokinase Phosphofructokinase
Phosphoglucoisomerase
(continued)
(see next slide)
Fructose-1,6-bisphosphate
Dihydroxyacetonephosphate
Glyceraldehyde-3-phosphate (G3P)
Isomerase
Aldolase
(see previous slide)
Energy capture phaseFour ATPs and two NADH produced per glucose
2 ATP
2 ADP
(G3P)
5 steps
P(G3P)
Pyruvate Pyruvate
NADH
NAD+
P
2 ATP
2 ADP
NADH
NAD+
Net yield per glucose:Two ATPs and two NADH
Glycolysis Formation of acetyl coenzyme A
Citric acid cycle
Electron transport and chemiosmosis
Glucose
Pyruvate
2 ATP 2 ATP 2 ATP
1. Piruvato pasa a la mitocondria2. Piruvato se rompe en CO2 y acetil –CoA (2
carbonos)3. Se genera un NADH por cada molécula de
piruvato4. Decarboxilación oxidativa
Pyruvate
Acetyl Coenzyme A
Carbon dioxide
NADH
NAD+
Coenzyme A
Glycolysis Formation of acetyl coenzyme A
Citric acid cycle
Electron transport and chemiosmosis
Glucose
Pyruvate
2 ATP 2 ATP 2 ATP
1. Acetil entra al ciclo de Krebs
2. Se produce CO2
3. Se reducen las coenzimas NADH y FADH2
4. Se obtiene un ATP
Acetyl coenzyme A Coenzyme A
Citrate
NAD+NAD+
NADH
NADH
NADH
NAD+
CO2
ATP
GDPGTP
FADH2
FAD
H2O
ADP 4-carbon compound
CO2
Oxaloacetate
5-carbon compound
CITRIC ACID CYCLE
Coenzyme A
Oxaloacetate
Citrate Isocitrate
α-ketoglutarate
Glucose Fatty acids
Citrate synthase
Acetyl coenzyme AIsocitratedehydrogenase
α-ketoglutaratedehydrogenase
NADH
NADH
H2O H2OCO2
CO2
NAD+
NAD+
CITRIC ACID CYCLEPart 1
Coenzyme A
(see next slide) (see next slide)
Fumarate Succinate
Succinylcoenzyme AMalate
Coenzyme A
FADH2
FAD
Succinyl CoAsynthetase
Succinatedehydrogenase
(see previous slide) (see previous slide)
GTP
ADP GDP
ATPFumarase
Malatedehydrogenase
NADHNAD+
H2O
CITRIC ACID CYCLEPart 2
Glycolysis Formation of acetyl coenzyme A
Citric acid cycle
Electron transport and chemiosmosis
Glucose
Pyruvate
2 ATP 2 ATP 32 ATP
Reacciones de oxi-reducción, se transfieren electrones hasta que O2 acepta electrones e hidrógenos
Se produce H2O Ocurre en la membrana interna de la
mitocondria Se produce la mayor cantidad de ATPs
Figure 8-8 Biology: Life on Earth 8/e ©2008 Pearson Prentice Hall, Inc.
ATP
NAD
ADP+Pi
NADH FADH2
FAD
H2O2H+2e–1/2O2
intermembranespace
innermembrane
matrix
Oxygen is requiredto accept energy-depleted electrons.
H+ channel is coupled toATPsynthesizing enzyme.
Flow of H+ downconcentration gradientpowers ATP synthesis.
High H+ concentration isgenerated by active transport.
High-energy electron carriersfrom acetyl CoA formation, Krebscycle, and glycolysis feed into the ETC.
Energy fromhigh-energy electronspowers activetransport of H+ by ETC.
Cytosol
Intermembranespace
Outer mitochondrial membrane
Inner mitochondrial membrane
Matrix of mitochondrion
NADHNAD+
FADH2
FAD 2 H+
H2O1/2 O2
Complex I:NADH-ubiquinoneoxidoreductase
Complex II:Succinate-ubiquinonereductase
Complex III:Ubiquinone-cytochrome coxidoreductase
Complex IV:Cytochrome coxidase
Cytosol
Intermembranespace
Outer mitochondrial membrane
Inner mitochondrial membrane
Matrix of mitochondrion
Complex I Complex II
Complex III
Complex IV
Complex V:ATP synthase
(a)
Glycolysis
Glucose
Pyruvate
2 ATP
2 ATP
NADH
Acetyl coenzyme A
Citric acid cycle
Electron transport and chemiosmosis
2 4 – 6 ATP
NADH2 6 ATP
NADH6 18 ATP
FADH22 4 ATP
32 - 34 ATP
Total ATP fromoxidative phosphorylation
Substrate-levelphosphorylation
Oxidativephosphorylation
PROTEINS CARBOHYDRATES FATS
Aminoacids
Glycerol Fattyacids
Glucose
G3P
Pyruvate
Glycolysis
CO2
AcetylCoenzymeA
Citricacidcycle
Electrontransportandchemiosmosis
NH3 H2O CO2
Endproducts:
Fermentación láctica
En ausencia de oxígeno Célula muscular Se produce ácido
láctico
Dos ATP
Fermentación alcólica
En ausencia de oxígeno Célula de levadura Se produce alcohol
etílico y CO2 Dos ATP
Glucosa se fermenta Vino se prepara con levadura, azucar de las uvas
y se produce alcohol. El pan se elabora con levaduras, harina y azucar. Se obtiene Co2 que hace que la masa se expanda.
Figure E8-2 Biology: Life on Earth 8/e ©2008 Pearson Prentice Hall, Inc.