biology ch1

  1. living things
    all organisms descend from a single-celled ancestor
  2. viruses
    dont carry out physiological fuctions on their own yet and contain genetic material that evolves. prob evolved from cellular organisms
  3. unicellular organism
    single cell carries out all the functions of life
  4. multicellular
    made of many cells that are specialized cells that fulfill different functions
  5. discovered the microscope in the 1590's
    zaccharias and hans janssen
  6. hooke and leeuwenhoek
    improved and aplied the microscope to living organisms
  7. coined the term cells to describe the repeated structures he saw in cork tissue
  8. cell theory
    • cells are the basic structural and physiological units of all living organisms
    • cells are both distinct entities and building blocks of more complex organisms
  9. modern cell theory
    • all cells come from preexisting cells
    • all cells are similar in chemical composition
    • most of the chemical reactions in life occur within cells
    • complete sets of genetic info r replicated and passed on during cell division
  10. charles darwinn
    • natural selection
    • proposed that living things are descended
    • from common ancestors and therefore related to one
    • another
  11. species
    • a group of organisms that look
    • alike and can breed successfully with
    • one another
  12. the diversity of life is due to evolution by
    natural selection
  13. natural selection
    • Traits that increase the
    • probability that the organism
    • will survive and reproduce
    • will become more common in
    • the population.
  14. natural selection leads to
  15. dna
    • the information that is passed from
    • parent to daughter cells
  16. genome
    • sum total of all the DNA in the
    • cell
  17. All cells in a multicellular organism have
    the same
  18. repeating
  19. gene
    • a specific segment
    • of DNA molecule—
    • contains information for
    • making proteins
  20. The human genome is
    composed of about 3
    billion nucleotides
  21. mutations
    • Alterations of the genome are called mutations,
    • which can lead to the production of altered
    • proteins.
    • Mutations can occur spontaneously or be induced
    • by environmental factors such as chemicals and
    • radiation.
    • Most mutations are deleterious but occasionally
    • they prove beneficial.
    • Mutations are the raw material of evolution.
  22. cells acquire _____ from the environment
  23. nutrients
    • -supply energy and materials for
    • building biological structures (synthesis).
    • -molecules contain energy in the
    • chemical bonds.
  24. Life depends on the thousands of _____ that occur within cells, all of which
    require materials to be moved into and out of
    cells in a controlled manner.
    chemical reactions
  25. cells are specialized and organized into
  26. tissues are organized into
  27. individuals are a part of
  28. Interacting populations of many different
    species form a
  29. Interacting communities in a given area
  30. Study of one type of organism can usually be generalized to
    other organisms (because all share a common ancestor, genetic
    code, and similar cellular structures).
  31. •Bacteria taught us our basic understanding of chemical reactions in cells.
    •The biochemistry of photosynthesis came from experiments on a pond alga, Chlorella.
    •Much knowledge of plant genetics has come from studies on Arabidopsis.
    •Knowledge about the genetics of animal development has come from sea urchins,
    roundworms, frogs, fish, chickens, and fruit flies.
    model systems
  32. all species on earth share a common
  33. Modern molecular methods allow
    biologists to compare genomes.
    • The greater the distance between
    • genomes, the more distant the common
    • ancestor.
  34. Earth is about 5 billion years old
    Life arose by chemical evolution.
    Chemical evolution led to the appearance of life about
    4 billion years ago
    Random inorganic chemical interactions eventually
    produced more complex molecules.
    Molecules that could reproduce themselves were
  35. Control over entrance, retention, and exit of molecules was possible because of
    compartmentalization by
  36. Around 3.8 billion years ago certain molecules became enclosed in fatty
    compartments or
  37. cells were tiny packages of molecules that lived separately from one another and had
    no internal membrane-enclosed compartments.
    prokaryotic cells
  38. consequences of photosynthesis
    • • O2 accumulated in the atmosphere
    • • Aerobic metabolism began
    • • Ozone layer formed—allowed
    • organisms to live on land
  39. evolved from prokaryotes
    Eukaryotic cells
  40. organelles
    • membrane bound
    • compartments with specialized functions:
    • • Nucleus
    • • Chloroplast
  41. Cellular specialization
    • Cells became
    • specialized to perform certain functions.
  42. all orgnisms on earth today descended from an original unicellular organism that lived around 4 billion yrs ago
  43. species two names
    • genus name- share common ancestor (homo)
    • species name- identifies within the genus (sapiens)
  44. 3 domains of life
    • • Bacteria
    • • Archaea
    • • Eukarya
  45. Multicellular Eukarya (plants, animals,
    and fungi)
    • evolved from protists—
    • unicellular microbial eukaryotes.
  46. autotrophs
    • organisms capable of
    • photosynthesis
  47. heterotrophs
    • require a source of
    • molecules synthesized by other
    • organisms
  48. independent variable
    • the variable being
    • manipulated
  49. dependent variable
    • the response that is
    • measured
Card Set
biology ch1