Biological Macromolecules:

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Biology 11McIntyre

• Biological Macromolecules

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Organic Compounds

• No official definition.
• Can be defined as
• a compound containing hydrocarbon groups.
• a compound containing a significant amount of
  carbon
• We will typically be considering compounds that
  are important to organisms carbohydrates,
  lipids, and proteins.

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Carbohydrates

• Major source of energy from our diet
• Most abundant organic compounds in nature
• Serve both as structural compounds and as energy
  reserves to fuel life processes
• glucose, a six carbon sugar (C6H12O6) is the
  immediate energy source to cells.
• Composed of the elements C, H and O in a 121
  ratio. Empirical formula is Cm(H2O)n
• Millions of tons produced by plants algae every
  year by via photosynthesis
• saccharide and the suffix ose refer to sugar.
  i.e. glucose or monosaccharide.

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Types of Carbohydrates

• Monosaccharides
• Single sugars
• Disaccharides
• Contain two monosaccharide units
• Polysaccharides
• Contain many monosaccharide units

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Types of Carbohydrates

• Monosaccharides
• glucose (primary energy source for cells)
• Fructose (found in some fruit, semen)
• Galactose (not normally found in nature)

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Types of Carbohydrates

• Disaccharides
• Contain two monosaccharide units
• maltose (glucose glucose)
• sucrose (glucose fructose) table sugar
• Lactose (glucose galactose) in dairy

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Types of Carbohydrates

• Polysaccharides
• Contain many monosaccharide units
• AKA complex carbohydrates
• Several hundred to several thousand
  monosaccharide subunits. Some are chains, some
  are branched
• Starch (plants store energy as starch. Animals
  eat it for energy)
• Glycogen (stored for energy in liver/muscles by
  animals)
• Cellulose (cell walls)

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Structure of Glucose

• Formula for glucose is C6H12O6
• Glucose readily forms a ring structure when
  dissolved in water. Carbons 1 to 5 and an oxygen
  form the hexagon ring. The 6th carbon hangs off
  the ring.

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Vocabulary Practice

• Disaccharide
• Glycogen
• Cellulose
• Monomer
• Sucrose
• Polymer
• polysaccaride

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Lipids

• All Lipids are hydrophobic (dont mix with
  water). Consist of carbon, hydrogen and oxygen
• Contain fewer polar O-H bonds and more non-polar
  C-H bonds than carbohydrates.
• includes fats and oils, waxes, phospholipids,
  steroids, and some other related compounds.
• Primarily energy sources and structural compounds
  and signaling molecules.
• release a larger amount of energy than other
  organic compounds. Fats yield 9 kcal/gm,
  carbohydrates 4kcal/gm

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Types of Lipids

• Lipids with fatty acids
• Triglycerides (Fats and oils)
• Phospholipids
• Waxes
• Lipids without fatty acids
• Steroids

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Types of Lipids Triglycerides

• Made of three fatty acids bonded to a glycerol
  molecule. Fats (solid at room temperature) and
  oils (liquid at room temperature) are
  triglycerides.
• Simple detailed

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Types of Lipids

• Phospholipids like a triglyceride with one
  fatty acid replaced with a phosphate group.
• phosphate heads are hydrophilic (water soluble)
  but tails are hydrophobic (water insoluble).
• spontaneously form micelles in water.
• very important because they form biological
  membranes

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Steroids (Sterols)

• Compact hydrophobic molecules containing four
  fused hydrocarbon rings
• Examples
• Cholesterol-precursor
• to sex hormones and
• vitamin D
• Sex hormones

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Proteins

• Where do we find Proteins?
• What do gelatin desserts, hair, antibodies,
  spider webs, blood clots, egg whites, tofu, and
  fingernails all have in common? They are all made
  of protein.

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proteins

• genetic information in DNA codes specifically for
  the production of proteins
• 50 of the dry mass of most cells
• As with carbohydrates and lipids, their
  three-dimensional structure is directly related
  to their function
• Type Examples
• Structural tendons, cartilage, hair, nails
• Contractile muscles
• Transport hemoglobin
• Storage milk
• Hormonal insulin, growth hormone
• Enzyme catalyzes reactions in cells
• Protection immune response

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Proteins Basic Characteristics

• Proteins are amino acid polymers
• central carbon atom surrounded by an amino group,
  a carboxyl group, a hydrogen atom, and a variable
  group of atoms called a side chain, usually
  symbolized by the letter R.
• There are 20 different R groups commonly found in
  living organisms and, so there are 20 different
  amino acids.

General structure of an amino acid
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The Peptide Bond

• Amino acids are bonded together by peptide bonds.
  So two amino acids bonded together form a
  dipeptide. Many amino acids bonded together form
  a polypeptide.

A polypeptide is many peptides joined together
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Vocabulary

• Polar
• Non-polar
• R-group of amino acid
• Peptide bond
• Amino acid