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	~~~  REDUCING  EQUIVALENT  TRANSFERS  ~~~
"Reducing Equivalent" = the form in which the electron 
	is transferred in oxidation/reduction reactions, 
	whether as [e-] or [H]. 
The particular type of reducing equivalent transferred 
	depends upon the reactants involved and upon certain 
	solvent characteristics such as polarity and pH. 
When the reactive group transferred is meerely an electron [e-]
	a difference in charge or valence only is noted 
	in the chemical equation.
When the transferred electron [e-] 
	is accompanied by a proton [H+] 
	then a hydrogen atom [H] is noted 
	as the reactive group transferred. 

	CONDITION:        pH:        SPECIES:
	acidic -------- lower ------- [H]
	alkaline ------ higher ------  e-

EXAMPLES:   FADH2  +  CoQ  --->  FAD  +  CoQH2 
            AAH2  +  2Fe+++  --->  AA  +  2Fe++  +  2H+
            *Q-   +   O2     --->  Q   +  *OO-
            NADH  +  FAD  +  H+  --->  NAD+   +   FADH2

		~~~   OXIDOREDUCTASES   ~~~
- Most electron and hydrogen transfers which take place 
    in living things are facilitated or controlled by enzymes. 
- As a general catagory such are called "OXIDOREDUCTASES". 
- Specifically they are named according to their subtrates. 
- The reductant is named first, then a colon, 
    then the oxidant, then the term "oxidoreductase". 
EXAMPLES:     *  glucose-6-phosphate dehydrogenase
             **  glucose-6-phosphate : NADP+ oxidoreductase
              *  thioredoxin reductase
             **  NADPH : thioredoxin oxidoreductase
              *  glutathione peroxidase
             **  glutathione : peroxide oxidoreductase
              *  cytochrome a3
             **  cytochrone c : oxygen oxidoreductase
              *  xanthine oxidase
             **  xanthine : oxygen oxidoreductase

   ~~~  METABOLISM  OF  REDUCING  EQUIVALENTS  ~~~
Every important nutrient or reactive group in biological 
	chemistry has one or more metabolic pathways 
	which govern production, distribution, storage, 
	utilization, and elimination. 
Examples are: amino groups, sulfur atoms, carboxylic acids, 
	purines, minerals, vitamins, glycerides, phosphates. 
Similarly enzymatic pathways and control mechanisms exist 
	for the metabolism of electrons and hydrogen atoms. 
To accomplish this, all living things use electron/hydrogen 
	carriers of various types. 
These carriers are arranged and function in series known as 
	"electron transport chains". 
Alternatively these may be called 
	"biological electron transfer sequences". 
Reducing equivalents are passed from one carrier to the 
	next through these sequences under enzymatic control. 
If a particular reaction produces electrons or hydrogen atoms, 
	biological electron transfer sequences are present 
	to carry them away. 
If a particular reaction needs electrons or hydrogen atoms, 
	biological electron transfer sequences are present 
	to provide them. 

  ~~~  EFFECTS OF ALTERED CONDITIONS ON BETS  ~~~
	CONDITION:              REDOX:         FUNCTION:
	D & A normal- - - - - - normal - - - - normal 
	D increased - - - - - - redosis- - - - accelerated 
	D decreased - - - - - - oxidosis - - - inhibited 
	A increased - - - - - - oxidosis - - - accelerated 
	A decreased - - - - - - redosis- - - - inhibited 
	R & O decreased - - - - normal - - - - inhibited 
	R & O increased - - - - mixed- - - - - accelerated 
	toxic blockade- - - - - mixed- - - - - inhibited 
	component absence - - - mixed- - - - - inhibited 









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