1. Briefly describe the three states of matter
    • Three states:
    •    Solid (definite shape and volume)
    •    Liquid (definite volume, variable shape)          Gaseous (variable shape and volume)
  2. What are atoms? What are "elements"?
    Atoms: building blocks

    Elements: matter made of similar atoms
  3. Name the four elements that compose 96% of body mass
    • Nitrogen
    • Carbon
    • Oxygen
    • Hydrogen
  4. Describe the structure of atoms
    • very small = <0.1 nm or 0.0000001 cm
    • made up of protons, neutrons, and electrons
  5. How do different elements and isotopes differ in terms of atomic number, mass number, and atomic weight?
    Isotope: structural variation of an atom that has the same # of    protons, but different # of neutrons and weight
  6. What are radioisotopes? How are they used in modern medicine?
    • Isotopes that are unstable and spontaneously decompose into more stable forms
    •    Nuclear medicine: use of radioisotopes to diagnose and treat disease
  7. Briefly explain what are molecules, compounds, and mixtures, and how they differ from one another.
    • No chemical bonds in a mixture (physical properties of molecules are unchanged)
    •    Mixtures are separated by physical means (evaporation, filtering, freezing)
    •    Compounds are separated by chemical means (breaking bonds)
  8. What part of atomic structure determines the reactivity of elements?
    # of electrons in outer “valence” shell determines reactivity
  9. What are hydrogen bonds? In what type of molecules do hydrogen bonds form? How are hydrogen bonds different from ionic and covalent bonds?
    Form when partial positive charge (δ+) of a hydrogen atom attracts the partial negative charge (δ-) of a neighboring atom common in polar molecules form weak attractions compared to ionic and covalent bonds responsible for surface tension, intramolecular bonds (DNA, protein)
  10. Name and briefly describe the properties of water that make it vital to life
    • polar solvent properties- universal solvent- body’s transport medium
    • thermal properties- high heat capacity- high heat of vaporization
    • reactivity- hydrolysis = breaks bonds- dehydration synthesis = forms bonds
    • reactivity- hydrolysis = breaks bonds- dehydration synthesis = forms bonds
  11. Describe the structure of carbohydrates, with reference to the difference between mono-, di-, and poly-saccharides, and to hydrolysis and dehydration reactions
    rings of “hydrated” carbon biological roles:      -  fuel source       -  structural role (DNA backbone) can be in the form of monosaccharides, disaccharides, or polysaccharides
  12. Saturated vs. Unsaturated Triglycerides
    • Saturated: single covalent bond between carbon atoms fatty acid chains are straight solid at room temperature increase risk of heart disease
    • Unsaturated: one or more double bonds between carbon atoms fatty acid chains are kinked liquid at room temperature decrease risk of heart disease
  13. What are Phosopholipids
    glycerol + 2 fatty acids + 1 phosphate group polar (head) and non-polar (tail), or “amphipathic” biological functions    - cellular membranes
  14. What are Steriods
    4 interlocking rings of carbon some examples:     - cholesterol (cell membrane structure)     - estrogen and testosterone (sexual functions)     - bile salts (lipid digestion)     - vitamin D (bone growth)
  15. What are Proteins
    Precise assembly of amino acids with peptide bond, sequence determined by genetic code (DNA)
  16. Describe the two main classes of proteins and be able to name examples of each
    Fibrous: extended and strand-like, insoluble in water, and very stable structural (collagen and keratin) movement (actin and myosin)

    Globular: compact, spherical, water-soluble, less stable regulation (hormones) defense (antibodies) transport (hemoglobin) catalysts (enzymes)
  17. What are Mistakes
    Primary sequence can disrupt all structural levels of a protein
  18. What is Protien denaturation
    Wrong physical or chemical (pH, temperature) conditions can cause protein denaturation
  19. Anything ending in "Ases" means what?
    It meas that the chemical reaction has or is going to be catalized
  20. What Catalysts?
    Catalysts: accelerate the rate of biochemical reactions, by lowering activation energy required for reaction
  21. Adenosine Triphosphate(ATP)
    • “Energy currency” of living systems
    • Fuel molecules (ex. glucose, lipids) contain too much energy to be used at one time, slowly broken down Energy released used to make smaller packets of energy (ATP)
    • Energy stored in ATP is close to what is needed for most biochemical reactions
Card Set
Chapter 2 questions