CH 2 Flashcards - EXAM 1.txt

  1. Atoms
    • basic unit of all matter
    • made of protons, neutrons and electrons
  2. Atomic #
    number of protons (or # of electrons if atom is neutral)
  3. Atomic Mass
    # of protons plus # of neutrons
  4. Electron orbits
    • 1st inner orbital holds 2 electrons (lowest energy)
    • 2nd and 3rd outer orbitals hold 8 electrons each (the farther out, the HIGHER energy)
  5. Valency
    • # of electrons that are required to complete the outermost shell
    • ie: carbon, has a valency of needs 4 electrons to fill the 2nd shell & get 8 total in that shell
  6. Properties of water.
    Hydrogen bonds produces a polar molecule�so can DISSOLVE compounds. It makes up about 70% of organisms by weight. Acidity is based on ionization of water to H+ (acid) and OH- (base), so when equal, pH is neutral.
  7. Why is water such a good solvent?
    Hydrogen bonds produces a polar molecule�so can DISSOLVE compounds.
  8. Covalent bond
    • STRONGEST of bonds. Involves sharing of electrons between atoms. These are difficult to break. They can be polar or non-polar.
    • Non-polar involves no charge, atoms with similar electronegativies
    • Polar has a slight charge, ie: O-H, with oxygen having the higher electronegativity it is slightly negative, and H is slightly positive.
  9. ionic bond
    • Formed by an atom GAINING or LOSING electrons
    • Ie: NaCl, where Na gives up its electron to Cl. So it�s Na+ and Cl-
  10. hydrogen bond
    • WEAKEST of the three bonds. Formed from attraction of positively charged hydrogen (H) atom. This can be with Nitrogen or Oxygen commonly.
    • Hydrogen bonds occur in molecules such as water, or in DNA between molecules (C & G and A & T creating double helix)
  11. Macromolecules
    • very large molecules. All macromolecules are polymers and when they join, water is lost, so the reaction is a dehydration synthesis
    • divided into 4 classes
    • 1. proteins
    • 2. polysacchardies (carbs)
    • 3. lipids
    • 4. nucleic acids
  12. dehydration synthesis
    occurs when water is lost due to polymers joining together to form macromolecules
  13. hydrolysis reaction
    happens when macromolecules breakdown into smaller subunits, and water is added
  14. Proteins
    • Functional parts of the cell
    • Function depends on the SHAPE of the protein
    • 50% of cell dry weight
    • made of AMINO ACIDS (AA's)
  15. Bonds formed with proteins
    • peptide bonds: occur between an amino group (-) and the carboxyl group (+) of AA's.
    • the peptide bond formation is a dehydration synthesis reaction
    • 2 AA's = dipeptide
    • >2 AA's = polypeptide
    • 3 AA's = tripeptide
  16. Polymer/monomer
    A protein is a polymer, and an Amino Acid is a monomer
  17. Functions and/or role of proteins
    • enzymes that catalyze reactions
    • aid in shaping of certain BACTERIAL structures
    • involved in GENE regulation
    • nutrient procurement (takes nutrients)
  18. Structures of proteins
    • primary: made of peptide bonds
    • secondary: hydrogen bonds
    • tertiary: hydrogen bonds plus Ionic bonds b/w side chains
    • quaternary: same as tertiary
  19. Carbohydrates
    • contain Carbon, hydrogen and Oxygen
    • 1:2:1 ratio
    • polysaccharides: large molecules made of carbohydrates
    • oligosaccharide: short chain of carbohydrates
    • monosaccharide: 1 carbohydrates
  20. monosaccharides
    • classified by number of carbons present in the carbohydrate
    • ie: five carbon sugars = pentose (ribose & deoxyribose)
    • ie: six carbon sugars = hexose (glucose, fructose, galactose)
  21. dissacharides
    • 2 monosacchardies joining thru dehydration synthesis
    • ie: glucose + galactose = lactose
    • ie: glucose + fructose = sucrose
    • ie: glucose + glucose = maltose
  22. polysaccharides
    • cellulose most abundant, STRUCTURAL component of cell wall formed by many glucose molecules together
    • glycogen is carbohydrate STORAGE molecule
    • Dextran STORES carbon & energy for bac
  23. Nucleic Acids
    • FXN: Determine specific properties of the cell
    • 2 types: RNA and DNA
    • subunits are nucleotides
  24. Nucleotides
    • composed of 3 units
    • 1. nitrogenous base (C,G,A or T..or U)
    • 2. phosphate group
    • 3. 5 carbon sugar (deoxyribose..ribose)
  25. Bonds
    • Nucleotides joined by covalent bonds: b/w phosphate of one nucleotide and teh sugar of the other.. 5' to 3' direction
    • carbon 5 of phosphate is attached to carbon 3 of sugar
  26. DNA bonds
    • hydrogen bonds connect the two strands to make dsDNA
    • A2T, C3G
    • PURE As Gold (A & G are purines)
  27. RNA bonds
    • same as DNA, but..
    • thymine replaced by uracil
    • sugar is ribose vs. deoxyribose
    • exists as SINGLE strand
  28. Lipids
    • SMALLEST of the 4 macromolecules
    • insoluble in H20
    • 2 classes: simple and compound lipids
  29. Simple lipids
    • Contain ONLY C, H & O
    • ie: Fats, made of glycerol and Fatty acids
    • glycerol has OH groups which allow for binding of 3 fatty acids (triglyeride)
    • ie: steroids
  30. Compound Lipids
    • contain fatty acid, glycerol & OTHER ELEMENTS
    • ie: phospholipid
  31. Phospholipid
    • Major component in lipid CELL MEMBRANE
    • made of phosphate & 2 Fatty acids attached to a glycerol
    • phosphate is polar & soluble in water, fatty acids non polar & hydrophobic
  32. Saturated fats
    have all SINGLE bonds in fatty acid chain
Card Set
CH 2 Flashcards - EXAM 1.txt