Metabolism Flashcards
Glycolysis
Glucose -> Pyruvate in cytosol
1st 1/2: 6C glucose -> 2x3C glycerol-3-phosphate
2nd 1/2: 2x3C -> 2x pyruvate (4 ATP total prod)
Fermentation
Metabolism w/o O2
Pyruvate becomes ethanol or lactic acid and NADH
Only 2 ATP/glucose produced
Pentose Phosphate Pathway
Active in liver and adipocytes, NADPH regulated
1st 1/2: oxidative branch NADPH produced
2nd 1/2: Non-oxidative, creates imp 5C sugars (ex ribose)
Gluconeogenesis
Synth of glucose from non carbs
Insulin
Promotes glycolysis w/ increased glucose levels
Released from pancreas
Glucagon
Promotes gluconeogenesis and glycogenolysis w/ decreased glucose levels
Released from pancreas
Beta oxidation
2 FA oxidized at a time -> Acetyl-CoA in mitochondria
Begins around same time as gluconeogenesis
FADH2 and NADH prod for every 2C cleaved
Ketogenesis
Ensure brain and RBC get glucose 1st
Occurs in mitochondria of liver
VLDL
Transport triglycerides, phospholipids, and cholesterol from liver to other parts of the body
HDL
Picks up stray FA and triglycerides and brings themto the liver
Protein Catabolism
Hydrolysis of AA chains in small intestines via trypsin, chymotripsin, and carboxypeptidase
N excreted in urea
C chain as substrate for CAC
Epinephrine
Released with stress, increases glycogenolysis
Cortisol
Released with stress, increases gluconeogenesis
NADH
Drives ATP prod in ETC
NAD+ gains e- via H- and becomes NADH
e- carried to ETC to power ATP synthase
Citric Acid Cycle
Creates most NADH
Takes place in mitochondrial matrix
Each cycle (2 per glucose): 2C lost as CO2, oxaloacetic acid regenerated, 1 ATP, 2 NADH, and 1 FADH2
Electron Transport Chain
Series of proteins that carries e- from NADH to O2
O2 key regulator
ubiquinone and cytochromes as intermediate e- carriers
2-3 ATP per NADH, 2 ATP per FADH2
36 net ATP prod/glucose
Proton motive force
Created as H+ pumped into intermembrane space when e- passed along
ATP Synthase
Turns as H+ flows back across membrane
Leptin
Interacts with hypothalamus to signal fullness
