Cellular Respiration

#1 Glycolysis

Happens in the cytosol, substrate is Glucose (C6H12O6), products are 2 pyruvate, produces 2 ATP

#2 Transition RXN

Happens in the cytosol then goes to the mitochondrial matrix, substrate are 2 pyruvate, products are to acetyl-coA and 2CO2, produces 0 ATP 

#3 Krebs cycle

Happens in the mitochondrial matrix, substrates are 2 acetyl-coA, products are 4 CO2, produces 2 ATP

#4 Oxidative Phosphorylation

Happens across the inner mitochondrial membrane, substrates are 6O2, products are 6H2O, produces 26 or 28 ATP

Reductant is 

oxidized to form oxidized species 

Oxidant is

reduced to form reduced species

Biological work is fueled by 

ATP hydrolysis 

ATP hydrolysis (ATP—> ADP+Pi) is powered by

Endergonic reactions

ADP phosphorylation (ADP+Pi——> ATP) is powered by

Food metabolism

Food metabolism (cellular respiration) fuels

ATP synthesis

O2——>

diffuses into mitochondria (inhale), few forms H2O

CO2 ←———

diffuses out of the mitochondria into the bloodstream (exhale), waste product from oxidation of glucose 

where does oxidative phosphorylation happens?

It happens in the inner mitochondrial membrane (cristae)

electron transport chain (etc)

electrons pass through carriers—→ energy used to pump H+ into the inter membrane space

chemiosmois 

H+ flows back through ATP synthase—→ powers phosphorylation of ADP into ATP 

electron flows through ETC

exergonic

ADP Phosphorylation—→ ATP

Endergonic

ETC portion pumping

active transport

proton flow thru ATP synthase

facilitated diffusion 

what happens when the mitochondrial is power down? 

1)ETC shuts down 

2) H+ pumping stops 

3)[H+] =(G=0) 

4) ATP synthase loses power and oxidative phosphorylation stop 

5) pyruvate, NADG, and FADh2 stop moving into mitochondrion 

6) Cell must begin fermentation 

Low O2 causes the

mitochondria to shut down

Hypoxemia

low O2 in the blood

Hypoxia

low o2 in the tissues/cells

Insufficient FEA (Humans)

2 lactate (C3H5O3) +2H+ (Homolactic fermentation) 

Insufficient FEA (yeast) 

2 ethanol (C2H5OH) (Alcholic Fermentation) 2(CO2) 2acetaldehyde (C2H4O) 

7 causes of hypoxemia /hypoxia

COPBN, drowning, poisoning, lung disease, heart disease, RBC hemoglobin issue, blood clots

Gi tract benefits

short chain fatty acids

GI tract harm

H2, CO2, CH4, and H2S

Fates of CO2 

blood, urine, breath 

Glycogen hydrolyzed glucose in

pathway 1

triglycerides hydrolyzed

glycerol—→pathway 1 fatty acids——>oxidation to form aCOA—→pathway 3

proteins hydrolyzed

amino acids—→ transamination and deamination —→ pathways 2 and 3