Bio nutrition, metabolism and enzymes

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Bio nutrition, metabolism and enzymes
2011-10-18 16:34:04
biology nutrition metabolism enzymes

bio 160 ch 4
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  1. why is food important
    provides nutrients and energy - essential for life
  2. nutrients
    components in food that the body needs to grow, develop and repair itself
  3. energy
    the ability to do work, including building complex molecules
  4. macronutrients
    • nutrients that organisms must ingest in large amounts to maintain health
    • proteins
    • carbs
    • fats
  5. micronutrients
    • nutrients that organisms must ingest in small amounts to maintain health
    • vitamins
    • minerals
  6. proportions of nutrients in different types of foods
    • animal products - more protein per gram relative to carbs
    • plant products - more carbs relative to protein
  7. digestion
    • breaks larger molecules down into smaller subunits by a series of chemical reactions to break the bonds that hold food molecules together
    • proteins > amino acids which are ultimately assembled into new proteins that have many different functions in the body
    • carbohydrates > simple sugars which are used to build cell-surface markers and energy-storage molecules
    • fats > fatty acids and glycerol, which provide the building blocks to form cell membranes
    • nucleic acids (NOT macronutrients cuz they are provided in small amounts) > nucleotides
  8. essential nutrients
    those that are essential because our cells cannot synthesize them from smaller building blocks and must be obtained from our diet
  9. essential amino acids
    8 amino acids the human body cannot synthesize and must obtain from food
  10. how do cells store and retrieve energy
    making and breaking chemical bonds in metabolic reactions
  11. reaction
    process of chemical change
  12. reactant
    molecule that enters a reaction
  13. product
    the molecule remaining at the end of a reaction
  14. activation energy
    the energy required for a chemical reaction to proceed
  15. how do enzymes facilitate chemical reactions
    chemical reactions require energy, enzymes accelerate reactions by reducing their activation energy
  16. enzyme
    • protein that speeds up the rate of chemical reactions
    • (think of enzyme additions to cheese making to make the milk curdle faster)
  17. substrate
    compound or molecule that an enzyme binds to and on which it acts
  18. active site
    • the part of the enzyme that binds to substrates
    • each enzyme is made so that its active site fits only one particular substrate molecule or molecules
  19. cofactor
    an inorganic substance required to activate an enzyme (zinc, copper, iron)
  20. coenzyme
    small organic molecule required to activate an enzyme (vitamins)
  21. metabolism
    • all biochemical reactions occurring in an organism
    • includes catabolic and anabolic reactions
  22. catabolic reaction
    • any chemical reaction that breaks down complex molecules into simpler molecules
    • release energy by breaking bonds
  23. anabolic reaction
    • any chemical reaction that combines simple molecules to build more complex molecules
    • require energy to build complex molecules
  24. complex carbohydrate
    • polysaccharide
    • carbohydrate made of many simple sugars linked together (starch, glycogen)
  25. simple sugar
    • monosaccharide
    • carbohydrate made up of a single sugar subunit
  26. starch
    • complex plant carb made of linked chains of glucose molecules
    • source of stored energy
  27. glycogen
    complex animal carb made of linked chains of glucose molecules
  28. fiber
    complex plant carbohydrate that is not digestible by humans