METABOLISM

Energy needs of the body
1) Heat - body temperature
2) Mechanical - muscle contraction
3) Electrical - nerve impulse transmission
4) Chemical - biosynthesis
5) ActiveTransport - movement of molecules from regions where they are dilute to where they are concentrated

METABOLISM - the sum of all reactions occurring in the body
CATABOLISM - degradation; breaking bonds
......Digestion:
..........proteins hydrolyze to ----> amino acids ----> urea
...........di- & polysaccharides hydrolyze to ----> monosaccharides
..........fats & oils hydrolyze to ----> fatty acids and glycerol ---> oxidation
ANABOLISM - biosynthesis; making bonds
Coupled Reactions - two coordinated, concerted reactions, one release energy, the other requiring energy

ADP ------------------------> ATP ------------------------------------------> ADP
ADP + Pi ----> ATP + H2O stores energy for later use
H2O + ATP ----> ADP + Pi releases energy for use by cells

ETS : Electron Transport System- requires O2; occurs in mitochondria (oxidative phosphorylation)
Coenzymes NADH Nicotinamide Adenine Dinucleotide
FADH2 Flavin Adenine Dinucleotide
Cytochromes iron-containing enzymes of ETS
Oxidation loss of hydrogen, loss of electons
Reduction gain of hydrogen, gain of electrons

TCA Cycle: Tricarboxylic Acid Cycle or Citric Acid Cycle or Krebs Cycle - occurs in mitochondria; rate is determined by energy needs of the cell

	For each cycle:  	Reactants		Products
				1 acetyl-CoA		1 CoA
				3 NAD+			3 NADH + 3H+
				1 FAD			1 FADH2	}  to ETS
				1 ADP + Pi		1 ATP	}  to ETS
							2 CO2

Glycolysis - occurs in cytoplasm; series of reactions by which glucose is oxidized to pyruvate
1) Aerobic - in the presence of oxygen: produces acetyl-CoA, NADH + H+, and CO2
2) Anaerobic- in the absence of oxygen: produces lactic acid and NAD+


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