bio test 1

  1. hypothesis
    educated guess based on available information
  2. null hypothesis
    opposite of the hypothesis
  3. theory
    a hypothesis with a large body of evidence to support it
  4. law
    a well-tested theory that has become an immutable fact
  5. dependent
    variables must be held constant in an experiment
  6. independent
    variables that are allowed to fluctuate, the independent variable is the subject of the experiment
  7. control group
    a portion of the experiment that does not recieve a treatment, this shows a basehine companson with the portion of the group that recieves the treatment
  8. placebo
    a sugar pill used in drug trials, an individual in the trail will be unaware if they are recieving the treatment or placebo to eliminate pyschosomatic variables
  9. placebo effect
    some test subject will respond to a placebo because they are told it is an actual treatment
  10. double-blind study
    the experimenter(s) do not know whether an individual subject is getting the treatment or a placebo until the study is complete, this eliminates experimenter bias as a variable
  11. concept map
    a concept map is a diagram showing the relationships among concepts. They are graphical tools for organizing and representing knowledge.
  12. characteristics of life on earth
    • 1.cellular
    • 2.DNA based
    • 3.reproduction
    • 4.growth
    • 5.metabolism- use of energy
    • 6.homestasis-maintaining a steady state
    • 7.evolution
    • 8.carbon/water based
  13. organization of life
    • atoms
    • molecules
    • organelles
    • cells
    • tissues
    • organs
    • organ systems
    • organisms
    • population
    • community
    • ecosystem
    • biosphere
  14. atoms
    the smallest fundamental unit that retains the properties of the element (or compound)
  15. element
    one type of atom
  16. atomic number
    the number of protons in the nucleus of an atom
  17. nucleus
    the central part of the atom that houses the protons and neutrons
  18. orbitals
    the clouds surrounding the nucleus where the electrons exist
  19. what do the electrons do?
    they are involved in all chemical reactions. they give and atom or molecule its unique chemical properties
  20. how do electrons store energy?
    the orbitals that electrons are in are layered like an onion would be. when atoms absorbs energy, like a sponge absorbs water, and electron can be moved to a layer further out that it normally would be. when this occures the electron has higher than it originally did
  21. atomic mass
    the number of protons and neutrons
  22. isotopes
    atoms with the same number of protons but different number of neutrons
  23. radioactivity
    certain isotopes are unstable and will spontaneously break down to form a more stable nucleus
  24. ions
    atoms are electronically neutral unless the number of electrons does not equal the number of protons
  25. chemical bond
    a type of force that holds two or more atoms together
  26. ionic
    an electron is taken from one atom by another atom "electron stealing"
  27. covalent
    electrons are shared between atoms "electron sharing"
  28. metal + non-metal=
    ionic bond
  29. non-metal + non-metal =
    covalent bond
  30. metal + multiple non-metal =
    both ionic and covalent bond
  31. electronegativity
    a measure of how strongly an atom holds on to its electrons
  32. polar covalent bond
    if two atoms in a covalent bond have significantly different elctronegativity values then a polar covalent bond is formed (the differnces should be between 0.5-1.7)
  33. hydrogen bonds
    hyrdrogen bonds form when a hydrogen atoms is directly bonded to an atom of nitrogen, oxygen, or flurine. hydrogen bonds are specific type of strong polar covalent bonds
  34. van der waals forces
    a weak type of attractions between molecules, this occurs when the covalent bonds of a molecule have a electronegativity difference of less than 0.5
  35. heat storage
    water conducts heat more effectively than air (approximently 6x effectively)
  36. ice formation
    as a solid water is less dense than as a liqued
  37. high heat of vaporization
    every gram of water that evaporates from human skin takes heat energy away from the body
  38. cohesion
    a abundant of hydrogen bonding water molecules stick together and at the surface of a body of water the molecules form a "skin". cohesion occures when molecules are attracted to other molecules of the same type. adhesion occures when polar molecules are attracted to different polar molecules
  39. high polarity
    water is sometimes called the universal solvent because many substances will dissolve in it. water has a polar covalent bond it will dissolve other molecules that also have polar covalent bond
  40. acid
    adding an acid to water will increase the number of H3o+ ions present
  41. base
    adding a base to water will increase the number of OH- present
  42. buffer
    solutions that are made to resist changes in pH
Card Set
bio test 1
chapter 1&2