1. Fatty acids
    • Saturated: all carbons are linked by single covalent bonds
    • --Tend to be solid at room temperature
    • Unsaturated: contain one or more double bonds
    • --1 double bond- monounsaturated
    • --2 or more – polyunsaturated
    • --Tend to be liquids at room temperature (oils)
    • Double bonds are easily broken down - not as strong
  2. Fats are important-
    • For energy storage
    • --1 gram of fat stores twice as much energy
    • --as 1 gram of glycogen or starch
    • Fats can also be structural in providing cushioning and insulation
  3. Phospholipids
    • Made up of: glycerol(not a lipid), 2 fatty acids and a phosphate group
    • Has a charge
    • Amphipathic molecule:
    • --Phosphate region- polar, hydrophillic
    • --Fatty acid chains- nonpolar, hydrophobic
    • Different from other lipids cause it has Phosphorus (P)
  4. Phospholipid
    • Polar head: sometimes will attach to a spot
    • - Hydrophilic
    • - Has a charge
    • - Attached
    • Nonpolar tail: Fatty Acids
    • - Hydrophobic
    • - No charge
    • - Unattached
  5. Steroids
    • Four interconnected rings of carbon atoms
    • --Usually not very water soluble
    • Cholesterol, Estrogen and testosterone differ only slightly
    • --Is a lipid
  6. Proteins/Peptide Bonds
    • Composed of carbon, hydrogen, oxygen, nitrogen, and small amounts of other elements, notably sulfur
    • --Amino acids are the monomers
    • Common structure with variable R-group
    • --20 amino acids
    • Side-chain determines structure and function
    • Peptides: Joined by dehydration or (condensation reaction) - loss of water, makes smaller
    • --Peptide bond - amino acids - protein
    • --Forms polypeptides
    • --Proteins are made up of 1 or more polypeptides
    • Broken apart by hydrolysis
    • Lirear - popar
    • Amino Acids: some are polar some are non polar
  7. 1. Primary structure
    • Amino acid sequence
    • --Determines what it is
    • Determined by genes
    • --how the structure comes together
    • Linear
  8. 2. Secondary Structure
    • Chemical and physical interactions cause folding
    • --Folds because if Hydrogen Bonds
    • Irregular or repeating
    • α helices and β pleated sheets
    • --Key determinants of a protein’s characteristics
    • “Random coiled regions”
    • --Not α helix or β pleated sheet
    • --Shape is specific and important to function
  9. 5 factors promoting protein folding and stability
    • Hydrogen Bonds: bond between polypeptide backbone and atoms in different side chains
    • Ionic Bonds: bonds between oppositely charged side chains
    • Hydrophobic Effect: nonpolar amino acids in center of protien to avoid contact with water
    • Van der Waals
    • Desulfide Bridge: covalent bond form between 2 cysteine side chains
  10. 3. Tertiary structure
    • Folding gives complex three-dimensional shape
    • Sometimes final level of structure
  11. 4. Quaternary structure
    • Made up of 2 or more polypeptides
    • --Protein subunits
    • --Multimeric proteins
    • --Form a functional protein
  12. Nucleic Acids
    • Responsible for the storage, expression, and transmission of genetic information
    • Has a negative charge
    • --Two classes
    • Deoxyribonucleic acid (DNA):Store genetic information coded in the sequence of their monomer building blocks
    • Ribonucleic acid (RNA):Involved in decoding this information into instructions for linking together a specific sequence of amino acids to form a polypeptide chain
    • DNA:Deoxyribose, AGCT, 2 strands-double helix, 1 form
    • --All amino acids put together
    • RNA:Ribose, AGCU, single strand, several forms
    • --decodes what those different molecules will do
  13. Monomer
    • A nucleotide
    • Made up of phosphate group (polar head), a five-carbon sugar (C5-H10-O5) (either ribose or deoxyribose), and a single or double ring of carbon and nitrogen atoms known as a base
    • --Sugar-phosphate backbone
Card Set
Cell Biology Chapter 3