Metabolism

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Metabolism

• Chapter 25

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Essential Nutrients
45 50 molecules must be ingested. This
includes representatives from the 4 major organic
molecule groups, plus a number of inorganic
substances such as including water, vitamins and
minerals (Na, Fe, etc.) The USDA has made major
revision in its nutritional recommendations. http
//www.health.gov/dietaryguidelines/dga2005/docume
nt/
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It was never based on solid science
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Nutrient A substance in food used by the body
for growth, maintenance, energy and repair.
USDA IOM for young adult female

• Carbohydrates 271g (55) 130g (45 - 65)
• Lipid total 65g (17) 20 25
• saturated 17g (7.8)
• Protein 91g (18) 56g (10 35)
• Water 1500 ml (average) per day.

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Uses of nutrients

• Carbohydrate Primary energy molecule. Also found
  on cell membranes and as part of structure of
  connective tissue matrix molecules
• Lipid Energy storage, plasma membrane structure,
  cushioning, steroid hormones.
• Proteins Enzymes, receptors, hormones,
  structures of all kinds. Must be complete or
  complimentary in order to supply essential
  amino acids.

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Essential amino acids
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Energy Metabolism

• Metabolism catabolism anabolism
• Cellular respiration is a series of catabolic
  reactions that provide energy for the production
  of
• This energy is used to generate ATP from
  phosphorylation of ADP.
• It is a series of Redox reactions.

ATP
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Energy Metabolism Generation of ATP
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Overview of aerobic respiration
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Summary of steps of energy metabolism
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Generation of ATP by substrate-level
phosphorylation
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Oxidative phosphorylation
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Overview of cellular respiration
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Carbohydrate Metabolism
Oxidation of Glucose
C6H12O6 6 O2 6 CO2 6 H2O 36 ATP Heat
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Glycolysis
It is the first stage in cellular respiration
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Stepsof glycolysis
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Aerobic vs anaerobic pathways
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Overview of Krebs cycle
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Krebs Cycle
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The ETC creates an chemiosmotic gradient
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The Electron Transport Chain
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Summary of ATP synthesisGains losses
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Visual summary of cellular respiration
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Glycogenesis/Glycogenolysis
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Gluconeogensis
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Summary of metabolic pathways
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Lipid metabolismoxidation
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Metabolism of Triglycerides
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Amino acid use in Krebs cycle
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Protein metabolism in the Liver
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Carbohydrate/fat amino acid pools
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Interconversion of carbohydrate, lipid and protein
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Pathways of the Absorptive state
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The effects of insulin on metabolism
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The Postabsorptive state
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Influences of Glucagon on blood glucose levels
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Composition of Lipoproteins
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Hypothetical feeding control mechanism
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Heat Balance
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Regulatory pathways for homeostatic control of
body temperature
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Temperature regulation mechanisms
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Maynard or Hans?