I.   Energy Production

     A.Metabolism refers to all chemical reactions within the body

1.Anabolism is building molecules from monomer forms to polymer forms, such as amino acids to proteins

2.Catabolism is breaking molecules from polymer form to monomer form, such as proteins to amino acids or glucose to ATP

          1.   Oxidation refers to removing electrons or H+

          2.   Reduction refers to gaining electrons or H+

     C.   Energy can come from:

          1.   Glycolysis

          2.   Fermentation

          3.   Cellular Respiration

          4.   Photosynthesis

     D.The process of cellular respiration converts:

C₆H₁₂O₆ + 6O₂ ---> 6CO₂ + 6H₂O + 36/38ATP/Heat

          1.   Glycolysis

          2.   Krebs's Cycle

          3.   Electron Transport Chain

II.   Glycolysis takes place within the cytoplasm of the cell

     A.Thought to be the most primitive form of metabolism since all cells use glycolysis

     B.Can be used under low oxygen conditions since it requires no O₂

     C.Process occurs in cells of the body since the net yield is (2) two ATP (-2ATP+4ATP=2ATP)

     D.   Metabolism states:

          1.in anaerobic conditions, the glucose produces pyruvate which be converted to:

               a.lactic acid in some cells of the body, such as muscle (but not neurons)

               b.ethanol and CO₂ in yeast cells (when denied O₂)

          2.in aerobic conditions the pyruvate enters the Krebs's cycle (Citric Acid Cycle)

     E.   Terminology

          1. ATP (adenosine triphosphate) = ADP (adenosine diphosphate) + Pi (inorganic phosphate)
 

(ATP = ADP + Pi + Energy)

          2.  NAD+ coenzyme - nicotinamide adenine dinucleotide

               NAD+ is oxidized form, exergonic reaction

               NAD-H + H+ is reduced form

(NADH+ + H+ +1/2 O₂ ---> NAD+ + H₂O)

     F.   Result is: Glucose + 2ADP + 2Pi + 2NAD ---> 2 Pyruvate + 2ATP + 2 NADH+H+ + 2 H₂O

III.Oxidation of Pyruvate

     A.   Pyruvate + NAD+ + CoA ---> Acetyl-CoA + NADH + CO₂

IV.Krebs's Cycle (Citric Acid Cycle) takes place within the matrix of the mitochondria in eukaryotic cells

     A.   oxidation of Acetyl CoA

     B.   Result is: CO₂ + ATP + NADH + FADH₂

V.Electron Transport Chain (Respiratory Chain) takes place within the inner membrane of the cristae

     A. it is referred to as oxidative phosphorylation

     B. it is aerobic cellular metabolism

     C. through redox reactions energy is stored in ATP, NAD-H and heat

     D. Cellular respiration

          1.   adds 34 ATP molecules for every glucose molecule, theoretical yield

          2.   use ATP for other needs within mitochondria, 30 actual yield

VI.   Fermentation involves anaerobic cellular respiration

     A.   Process is similar to glycolysis

     B.   Can be done under low or no O₂ by obligate or facultative anaerobes

     C.   O₂ can be toxic to some single-celled organisms

     D.   Process yields two ATP molecules
 

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